text:
\section{Introduction}
White dwarfs are the final evolutionary stage for the vast majority of single stars.
Characterised by long, steady cooling rates, white dwarfs can be used to infer properties of
the Milky Way like the the star formation history \citep[][]{Tremblay14}, the age of the disc
\citep[][]{Winget87, Oswalt96}, or their contribution to baryonic dark matter
\citep[][]{Reid01, Pauli03}.

Asteroseismology is a powerful tool for probing the internal structure of white dwarfs,
through the  study of multi-periodic variability that occurs during short-lived instability phases on the white dwarf cooling sequence  \citep[][]{Fontaine08, Winget08, Althaus10}.
Over the last few years, the NASA {\em Kepler} mission \citep[][]{Borucki10} and its re-purposed two-wheeled {\em K2} mission \citep[][]{Howell14}
have enabled high-precision asteroseismology of white dwarfs \cite[][]{Hermes11, Ostensen11, Greiss16}. Its successor, the NASA {\em
Transiting Exoplanet Survey Satellite} \citep[{\em TESS};][]{Ricker15}, will acquire all-sky times-series photometry for
at least two years,
searching for exoplanet transits and  enabling asteroseismology for many classes of stars \citep[][]{Campante16}.  Roughly 200\,000 selected
targets, including bright white dwarfs, may be observed with  2-min cadence. Full-frame images
will be taken every 30 min. The mission will survey areas of sky with one-month to one-year coverage,
depending on their ecliptic latitudes.

{\em TESS} is poised to return improved statistics building upon the original {\em Kepler}
mission and its ongoing {\em K2} reincarnation. In particular, the large sky coverage of {\em TESS}
will be excellent for the discovery of rare phenomena of which {\em Kepler} has so far
provided us with few, or even unique examples, e.g. the first direct detection
of a disintegrating asteroid at a white dwarf \citep[][]{Vanderburg15} or the
identification of stochastic outbursts in cool pulsating white dwarfs \citep[]{Bell15, Hermes15, Bell16}.
{\em TESS} is expected to be launched in 2018 March--July,
which is just before or at the same time of the second data release of the ESA
{\it Gaia} mission \cite[DR2;][]{Gaia16a, Lindergren16}.
Therefore, the need of an all-sky target list of bright white dwarfs is extremely urgent,
especially for the southern ecliptic hemisphere, which will not have the benefit of {\em Gaia} selection.
Bright white dwarfs can also be monitored by upcoming photometric missions,
such as Evryscope \citep{Law15} or the Next Generation Transit Survey \citep[NGTS;][]{West16}.

Traditionally, the identification of  white dwarfs relies on their blue colours
and relatively large proper motions. The availability
of accurate digital photometry and astrometry has greatly improved the efficiency of white dwarf selection
\citep[e.g.][]{Kawka06, Kilic06, Limoges13, GentileFusillo15, Raddi16, GentileFusillo17}.
Numerous efforts have been undertaken to improve the identification and
characterisation of bright and nearby white dwarfs \citep[][]{Sion14, Holberg16}, not only through spectroscopy and photometry
\citep[][]{Giammichele12}, but also including trigonometric parallaxes  \cite[e.g. DENSE
project\footnote{\url{http://www.DenseProject.com}};][]{Subasavage09}.
So far, the white dwarf census is strongly biased towards the
northern hemisphere, which \citet{Limoges15} estimate to be 78 per cent complete at 40\,pc.

In the following sections, we describe a collection of proper motions
and  multi-band all-sky photometry for potential {\em TESS} white dwarf targets.
Out of 2990 known white dwarfs brighter than 17~mag, we
re-identify 1864 stars, i.e. 62
per cent of the total. We discuss the properties of the sample and its completeness
via comparison with catalogues of spectroscopically
confirmed white dwarfs and the Lowell Observatory proper motion survey \citep[][GD sample]{Giclas80}.
We present photometry and proper motions for 305 new high-probability white dwarf candidates,
and 33 white dwarf candidates in the GD sample.
In the last part of the paper, we discuss the properties of 82 white dwarfs and 25 hot subdwarfs
for which we acquired follow-up spectroscopy.

\section{The data}
\label{chap2}
\begin{figure*}
\centering
\includegraphics[width=\linewidth]{cross_match}
\caption{In the first four panels, we show the evolving position of the newly confirmed white dwarf J0515+5021 (GD\,289). From left to right we display the cut-outs from the POSS-I and POSS-II blue plates, and the 2MASS\,$J$ and {\it GALEX} NUV images. The rightmost panel displays the PPMXL proper motion vector (in arcsec/yr, multiplied by 100  to improve the visualisation). In each panel, we plot the large cone-search of 45\,arcsec used to identify objects with large proper motions (in blue) and a 2-arcsec circle for the cross-match at the APASS position (in red).}
\label{f:cross_match}
\end{figure*}
The photometric identification of white dwarfs hotter than $\simeq 6000$\,K is very effective with colours sampling the flux across the Balmer jump, e.g. $ugr$ photometry of the Sloan Digital Sky Survey \citep[SDSS;][]{Girven11}.  Currently, there is no single all-sky survey covering this spectral region for magnitudes brighter than 17$^{\rm th}$ magnitude. A useful alternative is offered by the combination of  far- and near-ultraviolet photometry (FUV and NUV bands, centred at 1540 and 2270\,\AA, respectively) from the  {\it Galaxy Evolution Explorer}  \citep[{\it GALEX};][]{Morrissey07} with optical photometry from the AAVSO  Photometric All-Sky Survey \citep[APASS;][]{Henden14} in the Johnson $BV$ and Sloan $g'r'i'$ passbands.

\citet{Bianchi11} discussed the properties of hybrid colour-colour diagrams of {\em GALEX} and SDSS photometry showing their potential at separating classes of Galactic and extragalactic sources. \citet{Limoges13} have used similar colour-combinations to select white dwarfs candidates in the northern hemisphere  from {\it GALEX}, SDSS, {\it Hipparcos} \citep[][]{vanLeeuwen07},  and {\it Tycho-2} \citep[][]{Hog00}, using proper motions from SUPERBLINK \citep[][]{Lepine05}. In the work described here, we used the PPMXL catalogue which includes positions and proper motions for 900 million stars derived from USNO-B\,1.0  \citep[][]{Monet03} and the Two-Micron All-Sky Survey \citep[2MASS;][]{Skrutskie06} astrometry in the International  Coordinate Reference System (ICRS).
In addition to the ultraviolet, optical, and near-infrared photometry, we also added mid-infrared data from the  {\em Wide-field Infrared Survey Explorer} \citep[{\em WISE};][]{Wright10}.  In Table\,\ref{t:surveys}, we list the wavelength coverage of the used set of filters.
\begin{table}
\centering
\caption{Photometric bands used in this work. Refer to
the Spanish Virtual Observatory web pages$^{1}$ for the definition of
effective wavelength and width, $\lambda_{\rm eff}$ and $W_{\rm eff}$, respectively.\label{t:surveys}}
  \begin{tabular}{@{}lcrr@{}}
  \hline
Survey &  Filters & $\lambda_{\rm eff}$ & $W_{\rm eff}$ \\
 &   & [nm] & [nm] \\
  \hline
{\it GALEX} &  FUV & 154 & 25 \\
      &  NUV & 227 & 73  \\
APASS & $B$  & 430 & 84 \\
      & $g'$  & 464 & 116  \\
      & $V$  & 539 & 87 \\
      & $r'$  & 612 & 111  \\
      & $i'$  & 744 & 104 \\
2MASS & $J$ & 1235 & 162 \\
      & $H$ & 1662 & 251 \\
      & $K_{\rm s}$ & 2619 & 162  \\
{\em WISE}     & $W1$ & 3353 & 663 \\
      & $W2$ & 4602 & 1042  \\
\hline
\multicolumn{4}{l}{1) \scriptsize \url{http://svo2.cab.inta-csic.es/theory/vosa4/}}
\end{tabular}
\end{table}
\subsection{The reference catalogue: APASS}
APASS data release 9 \citep[DR9;][]{Henden16} contains $\approx 61$\,million objects in the  $10^{\rm th}$--$17^{\rm th}$ magnitude range.  The survey uses two pairs of 20-cm twin telescopes: two in the north at Dark Ridge Observatory in New Mexico, and two in the south at the Cerro Tololo Inter-American Observatory. This setup allows automated, essentially simultaneous observations in the $BV$ and $g'r'i'$ bands. The pixel scale at detectors is 2.57\,arcsec, and photometry is extracted using a 15\,arcsec aperture in the North and 20\,arcsec in the South, due to differences in the focusing of telescopes. APASS\,DR9 is suggested to be currently complete down to $V = 16$, and it is expected to be complete down to $V=17$ at the end of the survey. The bright limit of APASS is of little concern here, as there are only two known white dwarfs brighter than 10\,mag (i.e. Sirius\,B, and 40\,Eri\,B; see next section). The astrometric accuracy is 0.15\,arcsec  and the photometric accuracy is 0.02\,mag at 15\,mag \citep[][]{Munari14}. The release notes\footnote{\url{https://www.aavso.org/apass}} suggest a careful use of APASS photometry in crowded areas, where the photometry extraction algorithm suffers from blending. Furthermore, the most recent measures of $B$, $g'$ magnitudes in the north are known to carry large random errors, due to a technical problem with the detectors. Nevertheless, APASS photometry was shown to be sufficiently accurate for tying other deeper surveys onto an absolute flux scale \citep[e.g.][]{Barentsen14, Drew14, Shanks15}.

Duplicated entries are present in APASS\,DR9 due to merging issues at the detector corners and for high proper motion objects. Thus, we generated a reduced dataset of unique sources within a separation of $< 1.25$\,arcsec, which corresponds to half a pixel of APASS detectors.  When more than one photometric value is identified in this internal cross-match process, we adopted the brightest detection as suggested in the APASS\,DR9 release notes. The so defined unique list of APASS sources contained a little less than 59 million objects.

\subsection{Matching with PPMXL, {\em GALEX}, and {\em WISE}}

To cross-correlate APASS with {\it GALEX} and {\em WISE} detections, we needed  to account for stellar proper motions. Thus, we first queried the PPMXL database via Table Access Protocol (TAP), using the Starlink Tables Infrastructure Library Tool Set \citep[{\sc stilts};][]{Taylor06}. The query was run by uploading the entire unique APASS dataset to the online service\footnote{PPMXL is hosted by the German Astronomical Virtual Observatory data center at \url{http://dc.zah.uni-heidelberg.de/}}, split in to chunks of 100\,000 rows each. For each APASS source, we identified all the PPMXL objects within 45\,arcsec. Then, assuming epoch 2013.0 for the APASS\,DR9 coordinates, we forward-propagated the coordinates of PPMXL sources using their proper motions. Finally,  we
identified  good matches by selecting objects that fall within 2\,arcsec from the APASS sources.
The APASS-PPMXL cross-match produced $\approx 45$\,million objects.

The next step was to cross-match the APASS-PPMXL sources with the {\it GALEX}\,DR6+DR7 database\footnote{{\it GALEX}\,DR6+DR7 is hosted by the Mikulski Archive for Space Telescopes (MAST) at  \url{http://galex.stsci.edu/GR6/}}, accessing the Catalog Archive Server Jobs System (CasJobs) via Simple Object Access Protocol (SOAP). In CasJobs we first queried the PhotoObjAll table to search for all the nearby sources within 45-arcsec from the position of our APASS-PPMXL sources;
then, we identified the corresponding observing dates in the photoExtract table to propagate APASS coordinates to the corresponding {\it GALEX} epochs, again using the PPMXL proper motions. The cross-match with {\it GALEX} reduced further the number of APASS-PPMXL sources with proper motions and NUV photometry, leaving $\approx19$\, million
detections (i.e. about 15~million unique sources).

As last step, we cross-matched the APASS-PPMXL source list with {\em WISE} via TAP. Again, we shifted the APASS coordinates backwards in time by taking into account the epoch difference between APASS and {\em WISE}.

In Table\,\ref{t:x-match_summary}, we summarise the results of the cross-match procedure. It is important to stress here that we used the APASS-PPMXL-{\em GALEX}  (APG, hereafter) cross-match
to characterise and identify most of the white dwarfs described in this paper. We used {\em WISE} photometry to probe for infrared excess, e.g. the binary systems discussed in Section\,\ref{chap6.4}.

To visualise the cross-match procedure,  we display in Fig.\,\ref{f:cross_match} the identification of a newly confirmed white dwarf,  J0515+5021 (GD\,289). We note the star's significant proper motion across different epochs when the considered set of images was taken.
\begin{table}
\centering
\caption{Results of the all-sky cross-match.\label{t:x-match_summary}}
  \begin{tabular}{@{}lr@{}}
  \hline
Survey &  no. of objects \\
 &    \\
  \hline
APASS DR9 & 61,176,401\\
APASS DR9 unique & 58,756,366\\
APASS + {\em GALEX} (FUV and NUV) & 19,037,824 \\
APASS + {\em GALEX} NUV unique & 15,558,208 \\
APASS + PPMXL & 44,290,772\\
APASS + 2MASS & 42,901,844\\
APASS + {\em WISE}     & 43,179,834 \\
\hline
\end{tabular}
\end{table}
\begin{figure}
\centering
\includegraphics[width=\linewidth]{comparison_gd}
\caption{Assessment of the APG cross-match for the GD sample. ({\em Top}): solid histograms represent the APASS $V$-band magnitudes, proper motions, and angular separations between APASS coordinates and those available in VizieR. The step histograms represent the $V$-band magnitudes
available on VizieR . ({\em Bottom}): on the left, the differences between APASS magnitudes and those from the literature are plotted against the angular separation; on the right, we show the correlation between PPMXL proper motions, plotted against the angular separations. We use dark points to represent known white dwarfs and light coloured points for non white dwarf sources.}
\label{f:comparison_gd}
\end{figure}
\begin{figure}
\centering
\includegraphics[width=\linewidth]{GD_pm}
\caption{Colour-colour (top) and reduced proper motion (bottom) diagrams of the GD sample. The dark coloured contours in both panels represent the colour distribution of the field population, as inferred from our all-sky cross-match. The object classification is based on the information available from SIMBAD (see text). ({\em Top}):  white dwarf cooling sequences ($\log{g} = 7.0$--$9.5$ in 0.5\,dex steps) and the main sequence are plotted for reference;  both have been  determined by convolving \citet{Koester10} synthetic spectra and \citet{Pickles98} spectra with the filter transmission profiles, respectively. ({\em Bottom}): solid curves representing the expected reduced proper motions for $\log{g} = 8$ disc white dwarfs are plotted at three distinct values of tangential velocities,  $V_{\rm T} = 20$, 40, and 150\,km/s. The curves follow the relation: $H_{g} = g' + 5 \times \log{V_{\rm T}} - 3.379$. }
\label{f:GD_pm}
\end{figure}

\section{Assessing the cross-match}
\label{chap3}
To verify the completeness of the APG cross-match, we compared the data to a set of catalogues from the literature. Our first comparison is done against the GD sample
\citep[][]{Giclas80}  that contains blue stellar objects
with proper motions of $\lesssim 0.20$\,arcsec/yr and includes 311 previously known white dwarfs. In this work, we
have confirmed 12 new GD stars as white dwarfs.

During this operation, we visually inspected finding charts to confirm our re-identifications. We download cut-out images from the NASA SkyView service\footnote{\url{http://skyview.gsfc.nasa.gov/}},  i.e. blue and red frames of the STScI Digitized Sky Survey\footnote{\url{https://archive.stsci.edu/cgi-bin/dss_form}}, 2MASS, and {\it GALEX}, and for known white dwarfs we used finding charts available at the DENSE webpages, or those made available by Tom Marsh\footnote{\url{http://deneb.astro.warwick.ac.uk/phsaap/wdcharts/}}.

We make all the photometry and proper motions for the re-identified stars available on VizieR
\citep[hosted by the Strasbourg astronomical Data Center, CDS;][]
{Wegner00}. Table~\ref{t:schema} describes the columns that are included in the online tables.

\subsection{The GD sample}
\label{chap3.1}

The catalogue of blue stars from the Lowell Observatory proper motion survey contains 1710 unique objects. For this test we used the list of coordinates and magnitudes that is available on VizieR (catalogue ID, II/299); these quantities are an updated collection of data from other surveys and not just from the original work. Through our cross-match described above, we successfully retrieved APASS photometry, PPMXL proper motions, and {\em GALEX} photometry  for 1479, 1455, and 1175 stars, respectively. Of these stars, we re-identify APASS photometry for 257 white dwarfs. In Fig. \ref{f:comparison_gd}, the distribution of these magnitudes is compared to those from the GD catalogue as available on VizieR. In Fig. \ref{f:comparison_gd}, we also display the distribution of PPMXL proper motions ($\mu$) and angular separations between the APASS coordinates and those listed in VizieR. In the bottom left panel of Fig.\,\ref{f:comparison_gd},  we display the difference between the APASS\,$V$ magnitudes plotted against the angular separations (APASS -- VizieR coordinates). We measure a scatter of $\pm 0.15$\,mag around the zero.  Five white dwarfs are at more than 5-$\sigma$ from the zero: GD\,123, which has an M-dwarf companion; GD\,167, for which the $V$-band photometry recorded in VizieR is $\approx 2$\,mag brighter than those measured in other bands available on SIMBAD (also hosted by CDS); GD\,230, GD\,272, and GD 546, for which we suspect the APASS photometry to be blended with nearby objects. In the bottom right panel of Fig.\,\ref{f:comparison_gd}, we display the correlation between PPMXL proper motions and angular separations. The majority of GD stars follow a linear trend,  which is more evident for the known white dwarfs in the sample. After inspecting finding charts for these stars, we note that most of the scatter appears to be due to the limited accuracy of the reference positions that are listed in VizieR. The most discrepant white dwarfs, GD\,230 (with an angular separation of 9-arcsec, off scale in Fig.\,\ref{f:comparison_gd}), is likely blended with nearby stars.

We inspected the literature on GD stars available through SIMBAD and divided them into six groups: white dwarfs, white dwarf candidates, subdwarfs, stars, unknown objects, and QSOs. More than half of the GD stars have very little information available (i.e. no classification in the references) or no SIMBAD entry at all. In Fig.\,\ref{f:GD_pm}, we display the colour-colour and reduced proper motion  diagrams of stars with APASS-PPMXL-{\em GALEX} data (the reduced proper motion is defined as $H_{g} = g' + 5 + 5 \times \log{\mu}$, with the proper motion, $\mu$, given in arcsec/yr). We note that confirmed white dwarfs and hot subdwarfs mostly separate from the main group of other stellar objects. Based on the colours, reduced-proper motions, and the information available in SIMBAD, we identify 46 candidate white dwarfs, of which we observed 13 spectroscopically. In the GD sample, there are about 1100 objects with little or no information on SIMBAD, which have colours and proper motions that  compatible with those of main sequence stars.

\subsection{White dwarf samples}
 As seen from the previous test, the re-identification of known objects may present
some issues due to the poor accuracy of reference positions. This can be accentuated for
bright white dwarfs, because their coordinates were traditionally recorded in equinox B1950.0 with an accuracy of the order of 1\,arcmin \citep[e.g.][]{McCook99} and possess on average large proper motions. With the advance of technology,
higher accuracy is required, and there is an ongoing effort for updating the
astrometry and proper motions of known white dwarfs,
e.g. on SIMBAD and the Montr\'eal White Dwarf Database \citep[MWDD;][]{Dufour16}.

To assess the completeness of the APG cross-match with respect to
well studied white dwarfs, we took into consideration five spectroscopic catalogues that
include about 2/3 of the spectroscopically confirmed white dwarfs within the APASS magnitude range.  These are: i) the 25\,pc sample \citep[analysed by][]{Sion14}; ii) hydrogen (DA) and and helium (DB/DBA) white dwarfs from the European Southern Observatory  (ESO) supernovae Ia progenitor survey \citep[SPY;][respectively]{Koester09,Voss07}; iii) DA and DB white dwarfs analysed by the Montr\'eal group \citep[to be distinguished from the MWDD, which contains
a large fraction of the spectroscopically confirmed white dwarfs;][]{Gianninas10, Bergeron11}; iv) a bright selection ($g \leq 17$) of white dwarf plus main sequence binaries (WD+MS) from SDSS \citep[][]{Rebassa12}.  Covering most of the sky with Galactic latitudes of $|b|>30$\,deg, these catalogues allow for a semi-independent assessment of the photometric,  proper motion, and on-sky completeness of our APG dataset. We note that
for each catalogue we used the coordinates available on-line through VizieR, or SIMBAD.
Given that the accuracy of positions may be different in each catalogue,
this can lead to possible mismatches
and/or to non-identifications even for objects that are in more than one of the considered catalogues. When assessing the global-completeness,
we took in account the unique objects across the catalogues.
\subsubsection*{The local 25\,pc sample}
For this comparison, we use the list of \citet{Sion14}, which contains 223 white dwarfs. We identify APASS matches for 169 stars. The unmatched objects include Sirius\,B or Procyon\,B, which are outshined by their bright main sequence companions. In the top and bottom panels of Fig.\,\ref{f:comparison_sion14}, we display the comparison between APASS\,$V$ photometry and data available on SIMBAD for the \citet{Sion14} white dwarfs in the same band. For this sample, we measure a mean difference of $\pm 0.35$\,mag. Most of the outliers are due to contamination from nearby sources. We note that our cross-match becomes increasingly incomplete below 16.5\,mag, and we do not retrieve any of the white dwarfs fainter than 17\,mag (5 per cent of the total). The brightest white dwarf we re-identify is 40\,Eri\,B (APASS~$V = 9.3$).

The completeness of the cross-match with the \citet{Sion14} sample is reduced to 116 white dwarfs when we consider PPMXL proper motions. The highest proper motion we retrieve is 1.25\,arcsec/yr for WD\,2248+293. From Fig.\,\ref{f:comparison_sion14}, we note that we are about 60 per cent complete for white dwarfs with proper motions $\leq 1$ arcsec/yr.
\begin{figure}
\centering
\includegraphics[width=\linewidth]{comparison_sion14}
\caption{Assessment of the APG cross-match for white dwarfs in the 25\,pc sample. Refer to Fig.\,\ref{f:comparison_gd} for a description of each panel.}
\label{f:comparison_sion14}
\end{figure}
In the top right panel of Fig.\,\ref{f:comparison_sion14}, we present the distribution of angular separations between APASS and SIMBAD coordinates for the \citet{Sion14} white dwarfs. 40\,Eri\,B  is the star with the largest angular separation (52-arcsec). We do not plot WD\,0727+482A (with an angular separation of 90-arcsec, off-scale in Fig.\,\ref{f:comparison_sion14}), for which SIMBAD lists the coordinates of the companion.

In the bottom right panel of Fig.\,\ref{f:comparison_sion14}, we display the correlation between angular separations (APASS -- SIMBAD coordinates) and the proper motions. First, we note that the correlation follows closely a linear trend. Second, we fail to retrieve proper motions for stars with separations that are larger than 20 arcsec. Most of these objects move faster than 1.5 arcsec/yr. The lowest point not aligning with the others is WD\,0108+277, the astrometry of which may be affected by the presence of a nearby background source \citep[][]{Farihi05, Holberg16}.

\subsubsection*{White dwarfs from the SPY project}
\begin{figure}
\centering
\includegraphics[width=\linewidth]{comparison_samples}
\caption{Validation of the APASS-PPMXL cross-match. The coloured histogram bars represent APASS magnitude distributions ($V$ or $g'$, depending on the sub-sample considered) for the five white dwarf catalogues we used as reference: K+09: \citet{Koester09}; V+07: \citet{Voss07}; G+10: \citet{Gianninas10};   B+11: \citet{Bergeron11}; RM+12: \citet{Rebassa12}. The black outline-histograms represent the magnitude distributions of the known white dwarfs as retrieved from the literature. In the bottom-right panel, we plot the PPMXL proper motions against the angular separations between APASS coordinates and the positions available on VizieR/SIMBAD. Symbols are colour-coded with the same colours used of the histogram bars.}
\label{f:comparison_samples}
\end{figure}
SPY was an ESO spectroscopic survey that targeted bright white dwarfs ($B \leq 16.5$) south of $\delta = +25$\,deg \citep[][]{Napiwotzki03}. We tested the completeness of APASS on the DA and DB/DBA white dwarf catalogues published by \citet{Koester09} and \citet{Voss07}, respectively. We re-identified 575 of the 669 DA white dwarfs, and 61 of the 69 DB/DBA white dwarfs from SPY. The comparison between APASS magnitudes and those available in the literature is shown in the left panels of Fig.\,\ref{f:comparison_samples}.

We retrieved PPMXL proper motions for 547 DA and 59 DB/DBA white dwarfs. On average, proper motions of these stars are smaller in comparison with those of white dwarfs in the local sample, therefore we have an higher success rate in re-identifying these stars through our selection method. In the bottom-right corner of Fig.\,\ref{f:comparison_samples}, we display the correlation between PPMXL proper motions and angular separations between APASS and Vizier coordinates for the SPY sample. In the same panel, we plot also white dwarfs from the other samples discussed next. Proper motion and angular separations correlate well as found above for the \citet{Sion14} sample. Just a few objects (e.g. WD\,1334-678, WD\,1943+163, WD\,2029+183, and WD2157+161), which are blended with nearby stars may have inaccurate positions and/or proper motions.
\begin{table*}
\centering
\caption{Summary of the comparison between the APG cross-match with stars from the literature. \label{t:x-match_literature}}
  \begin{tabular}{@{}lccccl@{}}
  \hline
Catalogue &  no. of objects & APASS & PPMXL & {\em GALEX}\,NUV & reference \\
\hline
GD sample (all objects) &  1710  & 1479 & 1455 & 1175&\citet{Giclas80}     \\
GD sample (confirmed white dwarfs) &  323  & 260 & 246 & 174&     \\
25 pc & 223 & 169 & 115& 40&\citet{Sion14}     \\
SPY DA & 669 & 575 & 547 & 394&\citet{Koester09}     \\
SPY DB/DBA & 69 & 62 &59& 37 &\citet{Voss07}     \\
Montr\'eal DA & 1265 &889 & 822 & 546&\citet{Gianninas10}    \\
Montr\'eal DB/DBA & 108 & 72 & 70 & 48&\citet{Bergeron11}     \\
WD+MS & 92& 55 & 54 & 39&\citet{Rebassa12}     \\
\hline
Total white dwarfs & 1931 & 1388 & 1271 & 840 &    \\
\end{tabular}
\end{table*}

\begin{figure}
\centering
\includegraphics[width=\linewidth]{completeness}
\caption{Completeness of the dataset, expressed as fraction of the number of stars retrieved with respect to the total number of objects in the corresponding sample.}
\label{f:completeness}
\end{figure}
\begin{figure*}
\centering
\includegraphics[width=\linewidth]{samples_distribution}
\caption{Spatial distribution in equatorial coordinates of the known white dwarfs from the literature discussed here. Coloured symbols are used for the objects we re-identify in our multi-band photometric dataset (squares: DA white dwarfs; circles: DB/DBA white dwarfs; diamonds: WD+MS; stars: 25\,pc sample). White symbols correspond to white dwarfs with no APASS cross-match. The light grey-shaded area delimits the sky coverage of {\em GALEX}.
Iso-Galactic latitude curves are overplotted in blue.}
\label{f:samples_distribution}
\end{figure*}

\begin{figure*}
\centering
\includegraphics[width=0.85\linewidth]{samples_ccd_selection}
\caption{Colour-colour and reduced proper motion diagrams, obtained by combining {\em GALEX}, APASS, and 2MASS photometry. The number of objects plotted in each panel depends on the availability of the data (refer to Table\,\ref{t:x-match_literature} and Fig.\,\ref{f:completeness}). The dark coloured contours in both panels represent the colour distribution  of the field population, as inferred from our all-sky cross-match. Symbols used to distinguish distinct classes of white dwarfs are listed in  the top-left panel. The dashed curves in the top-right panel delimit the colour space where most known white dwarfs are found. White dwarf cooling sequences ($\log{g} =7.5$--$9.5$ in 0.5\,dex steps) and main sequence are plotted for reference in the three colour-colour diagrams. The expected proper motion curves for $\log{g}= 8$ Galactic disc white dwarfs are plotted in the bottom-left diagram. Also refer to the caption of  Fig.\,\ref{f:GD_pm} for further details. }
\label{f:samples_ccd_selection}
\end{figure*}
\begin{figure}
\centering
\includegraphics[width=\linewidth]{cut_pwd}
\caption{Selection of white dwarf candidates. ({\em Top panel}): colour-colour diagram showing the colour-cut (dashed lines) applied to select white dwarf candidates. The side-bar codes the assigned probability of being white dwarf, $P_{\rm WD}$, based on the reduced proper motion information. ({\em Bottom panel}): histogram distribution, on a logarithmic scale, of 1.5 million objects with $g'-r'\leq 0.5$ and ${\rm NUV} - g' \leq 4$, which we bin in ranges of $P_{\rm WD}$. We overlay the histogram distribution of  $P_{\rm WD}$ for known white dwarfs, candidate white dwarfs, and the white dwarfs and hot subdwarfs that we confirmed spectroscopically. }
\label{f:cut_pwd}
\end{figure}

\subsubsection*{DA and DB white dwarfs analysed by the Montr\'eal group}
These two white dwarf samples overlap to some degree with SPY, and consist of 1265 DA \citep[][]{Gianninas10} and 108 DB/DBA white dwarfs \citep[][]{Bergeron11}. The relevant differences with the SPY sample are their spatial distribution that extends to the northern hemisphere and a fainter limiting magnitude ($\approx 17.5$\,mag). We identified APASS photometry for 889 DA and 72 DB/DBA white dwarfs. The magnitude distributions of both samples are displayed in the top-right panels of Fig\,\ref{f:comparison_samples}. We note that the completeness starts decreasing for stars that are fainter than 16.5\,mag. In the bottom right panel of Fig\,\ref{f:comparison_samples}, we find a good correlation between proper motions and angular separations also for these stars; like before, a few discrepant objects (e.g. WD\,0927$-$173 or WD\,1545+244) are close to nearby sources that cause less accurate measures of proper motions or positions.
\subsubsection*{White dwarf plus main sequence star binaries}
\citet{Rebassa12} have produced  the so far largest catalogue of WD+MS binaries\footnote{\url{http://www.sdss-WDMS.org/}} from SDSS, which has been recently updated to the data releases 9 and 12 \citep[][]{Rebassa16}.  We selected a sample of 92 binaries with $g' \leq 17$, re-identifying APASS and PPMXL data for 55 and 54 of them, respectively. The magnitude distribution of the sample is displayed  in the bottom-left corner of Fig.\,\ref{f:comparison_samples}, while in the the bottom-right panel we add the corresponding data points to the comparison between PPMXL proper motions and coordinate separations.

\subsection{Completeness}
Table\,\ref{t:x-match_literature} summarises the tests of our combined
APG catalogues. The completeness of the cross-match depends on the intrinsic properties of the different test cases, e.g. the magnitude limits and accuracy of positions. In total, we have retrieved APASS photometry for 1388 white dwarfs out of a sample of 1931 stars (72 per cent).
We note that that the median magnitude of the white dwarfs for which we do not retrieve APASS data is $V \approx 16.5$, below which we are about 80 per cent complete. The completeness with respect to PPMXL and {\em GALEX} photometry is 66 and 43 per cent, respectively. A more detailed breakdown  into survey passbands is displayed in Fig.\,\ref{f:completeness}, for the spectroscopic catalogues considered earlier.

In Fig.\,\ref{f:samples_distribution}, we display the spatial distributions of the white dwarfs discussed in the previous sections. We checked for spatial clustering of the white dwarfs we could not re-identify. Most of the unidentified white dwarfs that were not recovered in our merged APG catalogue are in the Montr\'eal sample and are located along a strip stretching from $\alpha = +0$--$5$\,hr and $\delta = -30,\,+15$\,deg to  $\alpha = 8$--15\,hr and $\delta = +30,\,+40$\,deg. Some of them are from the Kiso survey \citep[][and references therein]{Limoges10},  which overlaps with the fainter end of APASS. We also note the traditional deficit of white dwarfs at low Galactic latitudes that is common to all the known samples of white dwarfs. At low latitudes, there is also no {\em GALEX} photometry, mainly due to the satellite avoiding bright stars and crowded areas in the Galactic plane (note the white areas in Fig.\,\ref{f:samples_distribution}).

Finally, we confirmed our results by checking all the remaining white dwarfs (where we define white dwarfs as objects with $\log{g}\geq6$) in the MWDD and SDSS \citep{Kleinman13,GentileFusillo15,Kepler15,Kepler16}, that is $\approx 1000$ objects brighter than 17~mag.  The overall completeness decreases to 62 per cent (1864 out of 2990 white dwarfs),
given that most of these additional stars are in the range of $g=16-17$.

\subsection{Candidate selection}
\label{chap3.4}
Having characterised the photometry of known white dwarfs,
we can use our merged APG catalogue to identify new white dwarf candidates. In Fig.\,\ref{f:samples_ccd_selection}, we display three colour combinations and a reduced proper motion diagram for the known white dwarfs. We  corrected {\em GALEX} photometry for non-linearity effects, using the results of  \citet{Camarota14}. In the top-left panel of
Fig.\,\ref{f:samples_ccd_selection}, DA white dwarfs are clearly distinct from main sequence stars when they reach $T_{\rm eff} < 12\,000$\,K $({\rm FUV} - {\rm NUV} > 1.3 ,\,{\rm NUV} - g' > 0.5)$.
In the top-right panel of Fig.\,\ref{f:samples_ccd_selection}, the $({\rm NUV} - g',\,g' - r')$ combination of colours is a proxy for the more commonly used SDSS $(u-g,\,g-r)$ diagram. The {\em GALEX}~NUV band samples a spectral range that is further away from the Balmer jump, resulting in a less stretched distribution of colours. We note a fairly good agreement between observed colours and the white dwarf cooling tracks, with an amount of scatter that is mostly due to the larger uncertainties of the APASS\,$r'$ magnitudes. It is worth noting the larger offset of some of the stars towards redder colours, which is a clear signature of the presence of late-type companions. The colour excess due to late-type companions becomes markedly evident when using 2MASS magnitudes, i.e. in the $({\rm NUV} - g',\,{\rm NUV} - H)$ panel of Fig.\,\ref{f:samples_ccd_selection}. Finally, the reduced proper motion diagram in the bottom left corner of this figure confirms the bulk of the re-identified stars as nearby, fast moving objects.

To select white dwarf candidates, we applied an (${\rm NUV} - g'$, $g' - r'$) cut based on the colours of the re-identified stars (Fig.\,\ref{f:samples_ccd_selection}). This colour cut reduces the contamination from main sequence stars that may share a similar colour space with white dwarfs of $T_{\rm eff} \lesssim 7000$\,K.  We then defined a selection criterion following the work of \citet{GentileFusillo15} on SDSS, which establishes a probability for an object to be a white dwarf. This probability,  $P_{\rm WD}$,  is inferred from the colours and the reduced proper motion of known white dwarfs in the ($H_{g}$, $g' - r'$) plane. Given the larger uncertainties of PPMXL proper motions with respect to those from SDSS,  we only define objects with $\delta \mu/\mu \leq 0.3$ and $P_{\rm WD} > 0.75$ to be good white dwarf candidates. Below this value, we found that the APASS-PPMXL probabilities disagree by more than $\pm\,25$ per cent with  those measured by \citet[][]{GentileFusillo15} for a sample of $\approx 300$ stars in common.

We identified 8000 objects within our colour-cut, of which $\simeq1200$ have $P_{\rm WD} > 0.75$.  Given the strict $P_{\rm WD}$ requirement, not all the known white dwarf fall within this selection, mostly because PPMXL proper motion uncertainties weight down their probabilities. In this
group of objects, we identified  391 that had not yet been spectroscopically confirmed as white dwarfs, ten of which are GD stars. We observed 77 high priority objects,
confirming 71 white dwarfs and six hot subdwarfs.
Due to scheduling constraints we also included in our target list objects
that fall outside the colour-cut or with $P_{\rm WD} < 0.75$,
achieving a lower rate of confirmed white dwarfs.

After our spectroscopic follow-up, we are left with
305 high-confidence white dwarf candidates with $P_{\rm WD} > 0.75$ and 33 GD stars
that do not have spectra or known spectral classification in the literature.  In Fig.\,\ref{f:cut_pwd}, we display the (${\rm NUV}-g',\,g'-r'$) colour-colour diagram of the candidate stars. In the lower panel of Fig.\,\ref{f:cut_pwd}, the histogram bars represent the $P_{\rm WD}$ of all objects with $g'-r'\leq 0.5$ and ${\rm NUV} - g' \leq 4$, i.e. about 1.5 million objects. We overlay step-histograms representing the $P_{\rm WD}$ of the known white dwarfs discussed in the previous sections, those for the 305 candidate white dwarfs, and those of white dwarfs and hot subdwarfs that we spectroscopically followed-up.

The photometry and proper motions for the 305 white dwarf candidates are made available through VizieR
in the format as listed in Table\,\ref{t:schema}. The photometry for the 135 stars that we have followed up will also be hosted on VizieR, with the inclusion of an additional column, ``short name'', that we use through the paper to refer to specific stars.

\section{Spectroscopic follow-up}
\label{chap4}
We obtained low-resolution spectra for 135 stars covering the wavelength range from the Balmer jump to slightly beyond the H$\alpha$ (3700--7500\,\AA).  The observations were spread over 2.5 years (2014 Jun/Jul, 2015 Mar/May, and 2016 Nov/Dec), and the data were taken at three different telescopes: the 3.6-m New Technology Telescope (NTT) at the ESO La Silla observatory, the 2.5-m Isaac Newton Telescope (INT) at the Roque de Los Muchachos Observatory, and the 1.82-m Copernico Telescope at the Ekar Asiago Observatory. Our targets were drawn from the APG list of candidates, the GD sample, and some objects that have lower $P_{WD}$.
We note that some of the targets (eight white dwarfs and ten subdwarfs; see next sections)
were previously known in the literature but with poorly accurate coordinates,
or that other research groups obtained classification during our follow-up operations.

At the NTT we used the ESO Faint Object Spectrograph and Camera 2 \citep[EFOSC2;][]{Buzzoni84} with the \#\,11 grism, a slit of 0.7\,arcsec, and binning 2x1 and 2x2, obtaining a resolution of 6.5--9.5\,\AA. The setup adopted at the INT produced a 3.5\,\AA\ resolution, mounting the Intermediate Dispersion Spectrograph (IDS) with the grating R400V a slit of 1\,arcsec and the blue-sensitive EEV10 CCD. For the Copernico setup,  we mounted the Asiago Faint Object Spectrograph and Camera (AFOSC) with the volume phase holographic grating, VPH7 \citep[][]{Zanutta14}, and a slit of 1.25\,arcsec, which deliver a resolution of 13\,\AA\ with a $2\times2$ pixels binning. The log of the observations is summarised in Table\,\ref{t:observing}.

The observations were done under different sky illumination (grey/bright at the NTT, dark/bright at the INT, dark/grey at the Copernico), with the seeing typically $< 2.5$\,arcsec, variable weather conditions often with thin clouds and during non photometric nights (especially during the second run at NTT, the second run at INT when calima affecting the sky transparency occurred, and the November runs at Asiago that
were affected by high humidity). We took 2--4 exposures per target, with exposure times  in the range of 300--1800\,sec.  On several occasions, we obtained multiple spectra of the same object across different runs to improve the total signal-to-noise ratio.

We took standard calibration frames (bias, dome flats) during each run, and arc lamps before and after the targets at the NTT and INT. We obtained a few arc lamps at beginning of the Asiago run (Ne and Hg+Cd separately, later combined during the data reduction), which were sufficient for an approximate wavelength calibration of the low resolution spectra. We also observed 2---3 spectrophotometric standards per night with a 5\,arcsec slit and we placed the slit at the parallactic angle for all the science and standard stars, in order to minimise flux-loss and to obtain a relative flux-calibration of the spectra, shown to be in good agreement with APASS photometry for most of the confirmed white dwarfs.  A few exceptions are the visually resolved WD+MS pairs, where we rotated the slit to include both the white dwarf and the late-type companion.

We used standard reduction routines to subtract the bias, to apply the flat-field correction and wavelength calibration, to optimally-extract the 1D spectrum, and for the flux calibration. Specifically, we used the {\sc starlink} suite of programs including {\sc pamela}\footnote{\url{http://starlink. eao.hawaii.edu/starlink}}\citep[][]{Marsh89} and {\sc molly}\footnote{\url{http://www. warwick.ac.uk/go/trmarsh/software/}}.
\begin{table}
{\scriptsize
\centering
\caption{Summary of instruments and number of spectra for the follow-up discussed in this paper.\label{t:observing}}
  \begin{tabular}{@{}llcclr@{}}
  \hline
Telescope &  Setup & $\Delta \lambda$ & Slit & Date & $N$\\
 &   &  [\AA] & [''] & &   \\
  \hline
NTT   &  EFOSC2/\#\,11 & 9.5  & 0.70 &2014/06/13--15 & 48  \\
      &         & 6.5--9.5  & 0.70 & 2014/07/11--13 & 34   \\
INT   &  IDS/R400V  &  3.5  & 1 & 2015/03/03--06  & 46   \\
      &         &    3.5  & 1.0 &2015/05/12--18 & 38   \\
Copernico & AFOSC/VPH7 & 13 & 1.25 & 2016/11/05 & 2 \\
                           &  & 13 & 1.25 & 2016/12/26--30 & 7 \\
\hline
\end{tabular}}
\end{table}
\begin{table}
\centering
\caption{Summary of spectral classification.\label{t:typying}}
  \begin{tabular}{@{}ll@{}}
  \hline
Type &  Number \\
  \hline
White dwarfs  (total) &  82  \\
     DA             &  60        \\
     DA+MS & 9         \\
     DAH &   1       \\
     DAB &   1       \\
     DB/DBA &   4       \\
     DC &   7       \\
Hot subdwarfs/BHB  &  25  \\
Other stars  &  28  \\
\hline
\end{tabular}
\end{table}
\begin{figure*}
\centering
\includegraphics[width=\linewidth]{da}
\caption{Spectra of the single hydrogen-atmosphere (DA) white dwarfs,
sorted by temperature. Where relevant, subtypes are included between brackets.}
\label{f:da}
\end{figure*}
\begin{figure}
\centering
\includegraphics[width=\linewidth]{dams_spectra}
\caption{DA+MS binaries sorted by temperature.}
\label{f:dams_spectra}
\end{figure}
\begin{figure}
\centering
\includegraphics[width=\linewidth]{dbc}
\caption{DBA, and DC white dwarfs.}
\label{f:dbc}
\end{figure}
\begin{figure*}
\centering
\includegraphics[width=\linewidth]{sd}
\caption{Hot subdwarfs and BHB stars sorted by temperature.}
\label{f:sd}
\end{figure*}
\begin{figure*}
\centering
\includegraphics[width=\linewidth]{da_lines}
\caption{Best fits of the Balmer lines for selected single DA white dwarfs (top row) and those in DA+MS pairs (bottom row). Synthetic spectra (black) are overlaid onto observed spectra (grey).}
\label{f:da_lines}
\end{figure*}
\begin{figure}
\centering
\includegraphics[width=\linewidth]{da_logg}
\caption{Best fits of H$\beta$ and H$\gamma$ lines for selected objects with $T_{\rm eff} \approx 20\,000\,K$ (top row), and $\approx 10\,000\,K$ (bottom row). Objects are plotted in order of decreasing $\log{g}$. Synthetic spectra (black) are overlaid on to observed spectral lines (grey).}
\label{f:da_logg}
\end{figure}

\begin{figure}
\centering
\includegraphics[width=\linewidth]{J2047-1259_zm10.eps}
\caption{Observed spectrum (grey) of the DAB white dwarf, J2047$-$1259, and the best-fit model spectrum (black) with $T_{\rm eff} = 18\,630 \pm 360$, $\log{g} = 8.37 \pm 0.6$, and [H/He]$ = -1$.}
\label{f:dab}
\end{figure}
\subsection{Spectral classification}
From a visual inspection of the multiple observations, we selected the best spectra for each star that we used for a quantitative classification. These spectra have a typical signal-to-noise ratio larger than 20. We confirmed 82 white dwarfs (eight of which were previously known) and 25 hot subdwarfs/blue horizontal branch (BHB) stars (ten of which were previously known). We classify the remaining 28 objects as A/F/G dwarfs, some of which have apparently large proper motions and colours that overlap with those of cool white dwarfs (see Fig.\,\ref{f:follow-up_ccd}).

The breakdown of the sample by sub-type is summarised in Table\,\ref{t:typying}. We identify 71 hydrogen atmosphere white dwarfs; in Fig.\,\ref{f:da}, we show 60 single objects (DA), one magnetic white dwarf with Zeeman splitting of the Balmer lines (DAH), and another that presents also helium lines (DAB). We classify nine white dwarfs as binaries with a late type companion (DA+MS), either on the basis of the near- and mid-infrared excess detected by 2MASS and {\em WISE} or from spectroscopic evidence (Fig.\,\ref{f:dams_spectra}).   Three of these systems were visually resolved at the NTT, thus we took spectra at non parallactic angles to include both stars in the slit. One star, J1022-3226, also displays a weak H$\alpha$ emission line  that could be produced from a chromospherically active companion.  Finally, we found four DBA white dwarfs, six objects that do not present any clearly detectable spectral features (DC) at the quality of our data (with the exception of J1010-2327, which has broad features in the blue part of the spectrum that may be either due to the presence of carbon in the atmosphere or to a strong magnetic field); their spectra are shown in Fig.\,\ref{f:dbc}.

We will not discuss the spectral classification of the hot subdwarfs and BHB stars in detail here. We roughly estimated their $T_{\rm eff}$ via a photometric fit to the NUV$BVg'r'$ photometry, using DA models with $\log{g} = 6$. We note that some of the stars have composite spectral energy distributions, which indicate the presence of a late-type companion. We display the spectra of these 25 stars in Fig.\,\ref{f:sd}, noting they span a range of temperatures between 11\,000--24\,000\,K. For the previously known stars, we advise
the reader to refer to the existing literature.

\begin{figure*}
\centering
\includegraphics[width=0.85\linewidth]{atmos_da}
\caption{Atmospheric parameters of DA white dwarfs.
The \citet{Fontaine01} cooling tracks are overplotted as dash-dotted curves for 0.2, 0.3, 0.4, 0.5, 0.6, 0.8, and 1.0\,M$_{\sun}$ from top to bottom, respectively. The empirical red and blue $T_{\rm eff}$ limits of the instability strip are shown \citep[dashed lines;][]{Gianninas15}. We mark in black one confirmed ZZ Ceti star, J0502+5401.}
\label{f:atmos_da}
\end{figure*}

\subsection{Atmospheric parameters of the spectroscopically confirmed white dwarfs}

For the determination of temperature and surface gravity ($T_{\rm eff}$, $\log{g}$) of the white dwarfs we used the software {\sc fitsb2}, which estimates a best-fit via $\chi^{2}$ minimisation using a downhill simplex algorithm \citep[][]{Napiwotzki04}. The $T_{\rm eff}$ and $\log{g}$ uncertainties were estimated via a bootstrap method. We used the \citet{Koester10} model atmospheres, which adopt a ${\rm ML}2/\alpha = 0.8$ mixing-length prescription for convective atmospheres and the Stark broadening  profiles of hydrogen lines computed by \citet{Tremblay09}.

For the 60 DA single white dwarfs we fitted six Balmer lines (H$\alpha$--H8), while we excluded the H$\alpha$ and H$\beta$ from the fit for the nine DA+MS pairs when the spectral profiles were altered by the presence of the companion star.  A few examples of the best-fitting results are shown in Fig.\,\ref{f:da_lines}, illustrating the quality of both the data and the fits. We also display in Fig.\,\ref{f:da_logg} an example of how the signal-to-noise ratio in the proximity of Balmer lines and spectral resolution are the relevant factors in assessing the surface gravity of selected objects, chosen at $T_{\rm eff} \approx 10\,000$ and $T_{\rm eff} \approx 20\,000$. To estimate $T_{\rm eff}$ of non-DA white dwarfs, we used a photometric technique fitting the available ultraviolet/optical data and keeping $\log{g} = 8$ fixed.

From the Copernico/AFOSC observations, we identified J0130+5321 (GD\,278) for which we had to arbitrarily fix $\log{g} = 6$ to obtain a satisfying fit of the spectrum and photometry. Its spectrum was acquired in good weather conditions, and presents only hydrogen lines at the resolution of the AFOSC setup.

The atmospheric parameters of the 60 single DA white dwarfs and nine DA+MS white dwarfs are listed in Table\,\ref{t:physical}. The eight stars that were previously known are: J0347$+$4358 J0502$+$5401, J0812$+$1737, J1455$+$5655, and J2233$+$2610 \citep[][]{Limoges13, Limoges15}, J0847-7312 \citep[][]{Gianninas10}, J1003$-$0337 \citep[GD\,110;][]{Kepler95}, and J1128$+$5919 \citep[][]{Girven11}. Our results
for $T_{\rm eff}$ and $\log{g}$ agree within 2--3\,$\sigma$ with those reported in the literature.

Among the hydrogen-dominated atmospheres, there are two peculiar objects. One is a magnetic white dwarf (DAH), J2109+6507, for which we kept $\log{g} = 8$ fixed and derived its $T_{\rm eff}$ through a fit of the photometric data. The second object is a DAB white dwarf, J2047$-$1259. We obtained two spectra, the first taken at the NTT on 2014 June and the second at the INT on 2015 May, which do not show sensible differences in the relative position  and appearance of spectral features. We initially estimated a $T_{\rm eff} = 17\,000 \pm 740$\,K and $\log{g} = 9.0 \pm 0.1$, using only the Balmer lines. We then attempted a fit with a grid of DAB model spectra, which sample different [H/He] compositions. In Fig.\,\ref{f:dab}, we show the improved agreement with a synthetic spectrum of $T_{\rm eff} = 18\,630 \pm 360$\,K, $\log{g} = 8.37 \pm 0.06$, and ${\rm [H/He]} = -1$.  The quality of our radial velocity information does not exclude the possibility that this system could be a close binary pair.

\section{Physical parameters}
\label{chap5}
We estimated masses and ages for the DA white dwarfs, the DAB white dwarf, and the DA+MS white dwarfs. We interpolated the physical parameters from the Montr\'eal cooling tracks, using the spectroscopic estimates of $T_{\rm eff}$ and $\log{g}$. For $T_{\rm eff} < 30\,000$\,K, we used the carbon-oxygen core cooling models with thick hydrogen layers, which are described by \citet{Fontaine01}. For hotter stars we used the carbon-core cooling sequence of  \citet[][]{Wood95}. We applied the \citet{Tremblay13} 3D corrections to the measured atmospheric parameters of cool DA white dwarfs ($T_{\rm eff} < 15\,000$\,K), which account for the inaccurate treatment of convection in 1D model atmospheres.  The physical parameters and the 3D corrections are given in Table\,\ref{t:physical}. The distribution of hydrogen-dominated white dwarfs in the ($T_{\rm eff}$, $\log{g}$) plane is displayed in Fig.\,\ref{f:atmos_da}, where most stars are found to have $\log{g} = 8.00 \pm 0.25$.

Seven stars have atmospheric parameters that are compatible with the instability strip of DA white dwarfs \citep[][]{Gianninas15,Tremblay15}. One is the already known ZZ Ceti star, J0502$+$540 \citep[][]{Limoges15, Green15}, for which we give more details in Section\,\ref{chap6.3}. The other six stars are candidate pulsators (cZZ in Table\,\ref{t:physical}).

Two low surface gravity stars, J0130$+$5321 (GD\,278) and J1142$-$1803, could potentially be extremely low mass white dwarfs (ELM). J0130$+$5321 would have a mass of $\approx 0.16$\,M$_{\odot}$ \citep[cf fig.\,3 in][]{Brown10}. J1142$-$1803 was previously classified as a subdwarf (sdB) by \citet{Kilkenny97}. It has narrow spectral lines as expected for a cool white dwarf ($T_{\rm eff} \approx 9000$\,K). This star has a ${\rm NUV} - g'$ colour that locates it between the white dwarf cooling tracks and the main sequence in the top left panel of Fig.\,\ref{f:follow-up_ccd}, in agreement with the low surface gravity estimate ($\log{g} = 6.76 \pm 0.28$), corresponding to $\approx 0.21$\,M$_{\odot}$.  Given that we used low-resolution gratings, we cannot rule out that at least GD\,278 is a metal-poor halo star \citep{Brown17}. Nevertheless, we note that both stars have relatively large proper motions that are compatible with those of white dwarfs.

\begin{figure*}
\centering
\includegraphics[width=0.85\linewidth]{follow-up_ccd}
\caption{Colour-colour and reduced proper motion diagrams of the 135 stars we have followed up. Symbols are clarified in the legend. For a description of synthetic tracks refer to Fig.\,\ref{f:samples_ccd_selection}.}
\label{f:follow-up_ccd}
\end{figure*}
\begin{figure*}
\centering
\includegraphics[width=\linewidth]{colours}
\caption{Assessment of the colour excess for the white dwarf sample. Each panel represents a set of colours, which combine from left to right {\em GALEX}, APASS, and {\em GALEX}-2MASS bands. On the y-axis is the colour excess, i.e. the observed  minus the intrinsic colours. The dashed line marks the $E(B-V) = 0.1$ colour excess in each panel. DA white dwarfs are plotted as white squares, red symbols are used for the DA+MS pairs, which appear with strong ${\rm NUV} - H$ excesses. Generally, this spectroscopic follow-up sample has minimal interstellar reddening.}
\label{f:colours}
\end{figure*}
\section{Discussion}
\label{chap6}
\subsection{Interstellar reddening}
\label{chap6.1}
The sample of white dwarfs discussed here is made up of relatively bright, but intrinsically
low-luminosity objects; thus, these are mostly nearby and suffer very little reddening.
In Fig.\,\ref{f:follow-up_ccd}, we display a selection of colour-colour and reduced proper motion diagrams for the observed stars, which offer a visual comparison with the same plots for the known white dwarfs from the literature (Fig\,\ref{f:samples_ccd_selection}). The confirmed white dwarfs and subdwarfs are all located within the dashed lines that we have chosen as colour cut for the identification of white dwarf candidates in Section\,\ref{chap3.4}. The only exception is the DC white dwarf, J0201+1212 (GD\,21). The contaminants, also shown in this figure,  are mostly outside the dashed lines and share the colour space of cool ($T_{\rm eff} < 7000$\,K) white dwarfs. Finally, we stress that the presence of cool companions to white dwarfs and hot subdwarfs is clearly evident in rightmost panels of Fig.\ref{f:follow-up_ccd},  where these objects depart from their typical single-star colours.

To confirm that the stars we observed are affected only by a small amount of interstellar reddening, we estimated the colour excess in four different colours in Fig.\,\ref{f:colours}. The leftmost panel of this figure displays the colour excess in the UV bands.  Although we attempted an empirical correction to reduce non linearity effects of {\em GALEX} photometry \citep{Camarota14},  a few hot stars (FUV$ - $NUV < 0.2\,mag) still have negative UV excess. This could be due to a wrong fit of the Balmer lines, leading us to overestimate $T_{\rm eff}$. However, in $B-V$ and $g'-r'$, most stars are consistent with $E(B-V)\le0.1$. Finally,  the NUV$-H$ colour in Fig.\,\ref{f:colours} clearly reveals the colour excess of the DA+MS systems due to the strong $H$-band contribution of their companions. We note that a few other stars follow the same trend as the DA+MS stars,  although with smaller colour excess. However, given that their 2MASS $H$ and $K_{s}$ are only upper limits, we exclude the presence of unseen companions.

\begin{figure}
\centering
\includegraphics[width=\linewidth]{comparison-gaia}
\caption{Comparison between {\em Gaia} $G_{\rm p}$, APASS\,$g'$ and $r'$ magnitudes, plotted against $g'-r'$ colours.}
\label{f:comparison-gaia}
\end{figure}

\subsection{Comparison with {\em Gaia}}
{\em Gaia} data release 1 \citep[DR1;][]{Gaia16b} photometry became public last year. Due to known issues with the chromatic correction in the astrometry of {\em Gaia}, not all the identified sources have been released \citep[1 per cent of the total number of detected sources;][]{vanLeeuwen16}. This problem has affected especially blue objects such as white dwarfs, including the {\em Tycho/Hipparcos} objects that could have already parallaxes \citep[][]{Tremblay17}

We searched the {\em Gaia} database within 1 arcsec from the APASS coordinates of
the 135 stars for which we have follow-up spectroscopy. We could find  $G_{\rm p}$ photometry for only
61 of them, including 42 white dwarfs or hot subdwarfs. In Fig.\,\ref{f:comparison-gaia}, we display the comparison between {\em Gaia} and APASS magnitudes. The underlying distribution represents the photometry for the GD sample, while we overlay on top the stars we have followed up spectroscopically. About 70 per cent of the GD sample was retrieved successfully.

We find a good correlation in the range of $g' - r'$ colours covered by our sample. There are just a few outliers, and the correlations appear to depart from linearity for $g' - r' < - 0.3$; however, we identified fewer objects in this magnitude range. The most discrepant object is J1212$-$3642
(not shown in Fig.\,\ref{f:comparison-gaia}), whose APASS $g'$ and $r'$ photometry is $\approx 1$\,mag fainter with respect to {\em Gaia} $G_{\rm p}$. {\em Gaia} DR1
contains only one source at 0.6-arcsec from the coordintates of J1212$-$3642. It does not
present detectable infrared excess or spectral peculiarities. With this information in hand,
we suggest that APASS photometry could be systematically off.
Other two spectroscopic objects that differ by 0.2--0.3\,mag from the one-to-one correlation, J1003$-$3145 and J1438$-$3127, are DA+MS binaries for which the presence of a companion can be
the source of photometric variability.

\subsection{White dwarf distances}
\label{chap6.2}
We estimated spectroscopic distances by considering no extinction, but we assumed an average scatter of $E(B-V) = 0.03$ that corresponds to 0.1\,mag of extinction in the $g'$-band. We estimated the intrinsic $g'$-band magnitudes by convolving the filter profile to appropriately scaled \citep{Koester10} synthetic spectra.  We propagated the $T_{\rm eff}$ and $\log{g}$ uncertainties in order to assess the scatter in synthetic magnitudes. We found that about 12 DA white dwarfs have spectroscopic parallaxes placing them within 40\,pc from the Sun. Only J0812$+$1737 was previously known to be at less than 40\,pc from the Sun \citep{Limoges13}. Of the other 11 stars, six are in the northern hemisphere and five in the south. The nearest white dwarf we identify is J1407$-$0626, for which we estimate a distance of 25\,pc. This is a cool white dwarf ($T_{\rm eff} = 8400$\,K), which has likely escaped previous searches due to its modest proper motion ($\approx 0.1$\,arcsec/yr). Next year, the ESA {\em Gaia} mission will deliver accurate parallaxes for this object, confirming or refuting its membership to the local sample within 25~pc from the Sun.

The remaining DA white dwarfs are all within 100\,pc from the Sun. The most distant white dwarf in the spectroscopic follow-up sample is in the hot DA+MS system, J1022$-$3226, at 288\,pc.

\begin{figure}
\centering
\includegraphics[width=\linewidth]{WDJ0502}
\caption{Confirmation of pulsations for J0502$+$540. The 4.5\,hr light-curve taken at the Warwick 1-m Telescope is shown in the top panel; the discrete Fourier transform is displayed in the bottom panel. The two main peaks are labelled, and the 3-$\sigma$ threshold is displayed as a red line. In the right corner is the window function that illustrates the frequency resolution of the discrete Fourier transform.}
\label{f:WDJ0520}
\end{figure}
\subsection{ZZ Ceti stars}
\label{chap6.3}
Fig.\,\ref{f:atmos_da} identifies seven white dwarfs that fall within the instability strip of hydrogen atmospheres. One of the stars, J0502$+$540, was previously classified as ZZ\,Ceti by \citet{Limoges15} and its pulsations confirmed by \citet{Green15}.
We re-observed this star on 2016 Jan 6 at the Warwick 1-m Telescope in La Palma for $\approx 4.5$\,hr with a 20\,s cadence. In Fig.\,\ref{f:WDJ0520} we display the Fourier transform of the light curve, where we identify two main periods in agreement with \citet{Green15}.

Among our sample, J2233$+$2610 was also observed by \citet{Green15} and found not to be variable to above 0.07 per cent. This star is about 1000\,K hotter than the empirical instability strip; thus, it is not expected to vary. The remaining candidates will be excellent targets for {\em TESS}, which will acquire detailed light curves enabling an unprecedented level of characterisation for these and other ZZ Ceti stars. Furthermore,  we stress that the brightest stars in our sample ($g<16$) are ideal targets for ground-based observations, e.g. with Evryscope \citep{Law15} or NGTS \citep[][]{West16} that currently provide detailed time-domain photometry with a large coverage of the Southern hemisphere.

\begin{figure}
\centering
\includegraphics[width=\linewidth]{dams}
\caption{Photometric fits of the DA+MS binaries, sorted by descending white dwarf temperature (from top to bottom). We display the white dwarf spectra (in blue), the low-mass companions spectra (in red), and the combined spectra (in cyan). We display all the photometric bands available as black dots. In the top panel, we also plot a cut-out of the H$\alpha$ region for J\,1022$-$3226, for which we detect a weak emission.}
\label{f:dams}
\end{figure}

\subsection{Late type companions}
\label{chap6.4}
We identified nine white dwarfs in our sample that display redder colours than isolated objects (Fig.\,\ref{f:colours}), which suggest the presence of late-type companion stars. We confirmed six of them based on spectroscopic evidence (e.g. composite spectra or the weak H$\alpha$  emission seen in the spectrum of J1022$-$3226; Fig.\,\ref{f:dams_spectra}).  For three of these stars, labelled in Table\,\ref{t:companions}, we could  visually resolve the companions when we acquired their spectra. Three further systems are proposed to have companions that are too cool with respect to the white dwarf to reveal their presence in optical spectra (J0520$+$2315, J0220$-$0736, and J2308$+$0658), but displaying infrared excess already in
the 2MASS $J$ band.

We derived the $T_{\rm eff}$ of companion stars via fits to the composite spectral energy distributions (SED), including {\em GALEX}, APASS, 2MASS, and {\em WISE}~$W1/W2$ photometry. We kept the atmospheric parameters of the white dwarfs fixed to those determined from the spectroscopic analysis (Table\,\ref{t:physical}) and we built a grid of spectra for low mass stars and sub-stellar objects, taken from the latest version of the BT-Settl models \citep[][]{Allard12}. We fixed the models' metallicity to solar and $\log{g} = 5$. We derived the  intrinsic magnitudes of white dwarfs and main sequence stars by convolving  the filter profiles with the appropriate models from the \citet{Koester10} library of synthetic spectra and the BT-Settl grid, respectively. Finally, we estimated the best fits through a $\chi^{2}$ minimisation of the available photometry with three free parameters, i.e. an absolute scaling factor, the relative flux of white dwarf and companion, and the atmospheric temperature of the secondary. The results of our fits are displayed in Fig.\,\ref{f:dams}.

We also estimated the companion masses, under the assumption they are dwarf stars. Thus, we first considered a semi-empirical initial-to-final mass relation \citep[][]{Catalan08}, from which we inferred the white dwarf progenitor mass. We then estimated the total age of the system, by approximating the stellar lifetime with a simple analytical expression \citep[e.g. ${\rm Age} = 10 \times M_{\rm prog}^{-2.5}$\, Gyr;][]{Wood92}. Finally, we determined the companion mass via interpolation of $T_{\rm eff}$ and age on the \citet[][]{Baraffe98, Baraffe03} tracks for low-mass and substellar mass objects. In Table\,\ref{t:companions}, we list the relevant physical properties of the companions ($T_{\rm eff}$, age, mass).

We found that most of the proposed companions have masses in the range of 0.1\,M$_{\sun}$, i.e. corresponding to late-M spectral types. Spectroscopic follow-up aiming at a better characterisation of these companions is necessary, especially for the least massive of them, J0510$+$2315\,B, that we only identify through its infrared excess. For this object, we infer a mass of 0.05\,M$_{\sun}$, compatible with a brown dwarf. Although the first brown dwarf candidate to be discovered, GD\,165\,B, is a companion to a known white dwarf \citep[][]{Becklin88}, sub-stellar white dwarf companions are rare, with an occurrence rate
of at most a few per cent, estimated from high contrast imaging techniques
\citep[][]{Farihi05,Hogan09}, transit surveys \citep[][]{Faedi11},
and searches for infrared excess \citep[][]{Girven11, Steele11}.

Another system worth mentioning is J1438$-$3127, for which we estimated a white dwarf mass of $0.36 \pm 0.04$M$_{\sun}$. A white dwarf of such a low mass could not have be formed in isolation within a Hubble time, implying it could be the product of binary interaction. \citet{Rebassa11} showed that low-mass white dwarfs are more frequent in short period (post common envelope) binaries than in the field or in wide binary systems, bringing observational evidence in support to binary interactions during the common envelope phase. Such
low-mass white dwarfs are suggested to have gone through the common envelope phase while on the first giant branch, implying that their progenitors had an initial mass of $\lesssim 1.8$\,M$_{\sun}$ \citep[][]{Zorotovic13} and consequently a lifetime  of $\gtrsim 2.3$\,Gyr.
Given that the evolution of such systems
is complicated by the common envelope phase, we do not derive a companion mass as done for the other
binaries.

\begin{table}
\centering
\caption{Physical parameters of the low-mass companions. \label{t:companions}}
  \begin{tabular}{@{}lD{,}{\,\pm\,}{4}D{.}{.}{2}c@{}}
  \hline
Name &  \multicolumn{1}{c}{$T_{\rm eff}$} &   \multicolumn{1}{c}{Age} & Mass \\%& Radius  \\
 &  \multicolumn{1}{c}{[K]} &    \multicolumn{1}{c}{[Gyr]} & [M$_{\sun}$] \\% & [R$_{\sun}$]\\
  \hline
J0219$-$6306\,B$^1$ &2900 , 170 & 2.05& 0.09\\
J0220$-$0736\,B     &2300  , 620 &11.70& 0.08\\
J0510$+$2315\,B     &2000  , 380& 0.40& 0.05\\
J1003$-$3145\,B     &3000  , 200 &11.55& 0.08\\
J1022$-$3226\,B     &2800  , 1050 & 1.24& 0.08\\
J1420$-$2457\,B$^1$ & 3000 , 360 & 3.37& 0.10\\
J1438$-$3127\,B$^2$ & 3300  , 140 & >2.30&  \\
J2221$-$0408\,B$^1$ & 3200  , 870  & 1.83& 0.15\\%
J2308$+$0658\,B     & 4000  , 480 & 1.80& 0.7\\
  \hline
\multicolumn{4}{l}{\scriptsize 1) Not observed at parallactic angle. Resolved binary.}\\
\multicolumn{4}{l}{\scriptsize 2) Suggested post-common envelope binary.}
\end{tabular}
\end{table}

\section{Conclusion}
\label{chap7}
We have produced a catalogue of bright white dwarf targets for the upcoming NASA {\em TESS}
mission as well as long-baseline photometric surveys such as Evryscope and NGTS.
The target list was compiled by cross-matching APASS, PPMXL, and {\em GALEX}.
The catalogue includes proper motions and multi-band photometry
for 1864 known white dwarfs brighter than 17\,mag.
Having validated our cross-match against the Lowell Observatory
proper motion survey \citep[][]{Giclas80} and catalogues of spectroscopically confirmed white dwarfs,
we identified 427 high confidence white dwarf candidates (including 46 GD stars). We presented follow-up spectroscopy for 82 white dwarfs and 25 hot subdwarfs/BHB stars (eight white dwarfs and ten subdwarfs in the sample were previously known). Among the confirmed white dwarfs, we have identified a few interesting objects, such as a DAB white dwarf, six bright ZZ Ceti star candidates, nine WD+MS binaries, and one white dwarf at 25\,pc from the Sun. This leaves 305 high-confidence white dwarf candidates and 33 GD stars
requiring follow-up spectroscopy to ascertain their nature.

The uninterrupted light curves that {\em TESS} will obtain for the proposed stars,
will provide unprecedented insight on their variability (ZZ Ceti stars), binary eclipses,
as well as important statistical information on transits from exoplanets or debris around white dwarfs. The 30-min full-frame exposures of the {\em TESS} mission will increase the chances of finding serendipitous transits, by also monitoring stars that are not included in the short-cadence list of targets.

We publish the collection of photometric data for all the previously know white dwarfs that we re-identified in our analysis, which will become particularly useful with {\em Gaia} DR2 in spring 2018. Statistical analysis of spectroscopy, photometry, and parallaxes can eventually be used to obtain a very accurate estimate of cooling ages \citep[e.g.][]{OMalley13,Si17} for this sample of known white dwarfs.

redpajama_set_name: RedPajamaArXiv


An assault on fly-tipping and "grotspots" across Holbeach is under way, with parish and district councils joining forces to tackle the problem.
Workers from the Pride in South Holland team and Holbeach Parish Council staff are together slowly cleaning up areas of the town.
But the purge on overgrown footpaths, graffiti, overflowing bins and fly-tipping is also happening in villages, such as Holbeach Bank, Holbeach Hurn, Holbeach St Johns and Holbeach St Marks.
Parish council clerk David Boyce said: "It's been a real journey trying to make the most of the services available to us, without increasing costs.
"But simple things like reacting instantly to fly-tipping reported by our litter picking team has made a real difference.
"Going out with the team during the early hours and empowering them to report more fly-tipping around the town has resulted in those areas being cleared more quickly."
Mr Boyce confirmed that at least six cases of fly-tipping in Holbeach had been reported to the district council over the last three months.
"Challenges with funding have meant that I have had to work harder on the strategy so that residents can really feel a change.
"Litter breeds litter but by improving our response times to reports of fly-tipping and reaching out to parish councils directly, we are starting to see a change."
Coun Paul Foyster, chairman of Holbeach Parish Council, said: "It has been so encouraging to meet with Tony and see the renewed investment into the town.
Coun Paul Foyster, chairman of Holbeach Parish Council.
"Opening up communication is the first step towards making real change which is why the parish council is asking residents to report grotspot areas, either on our Facebook page or by visiting our office at Coubro Chambers, West End, Holbeach so a priority list can be created and communicated.
"I am confident that, moving forward, the pledge of "the difference a day makes' will help see a real change on our streets.
"The residents are proud of Holbeach and it is great to be part of something that is taking this to the next level."


Skitterleap will be held in Wellington on the weekend of 27/28 October.
Already have 10 signups so expecting numbers to go close to 30. May drop a few due to university exams but in reality they need to HTFU - remember anything more than a C is a waste of effort! Oh wait, university has changed since I was tutored by Aristotle.
The Players Pack (including comp) has been posted on this blog previously. The only change is the removal of the restrictions on Flamers in the Daemons of Chaos army given the update delivered in White Dwarf this month.
If anyone is looking to offload some plague censers they don't use I'm looking to buy some.


Click here to download a printable version of the message notes and discussion questions for the weekend of 01.14.12.
Our Theology of Servanthood Or Why We Serve?
God C_______________________ Us to Serve.
Where do I (We) Serve? Who do I (We) Serve?
Note: Personal Spiritual Gifts Assessment forms are available at all Welcome Centers.
1 Are you currently serving anywhere inside or outside of the church? If so, describe what you do and how you got started.
2 What is the best serving experience you've ever had? How were you changed as a result of this experience?
3 Read John 13:1-17. What do we learn about serving from this example of Jesus?
4 Read Romans 12:6-8. In what ways do you believe God has uniquely equipped you to serve His Kingdom?
5 What does it mean to live a life that is "other centered" as opposed to "self-centered?" What changes can you make in your own life to put others ahead of yourself?
Click here to download a printable version of the message notes and discussion questions for the weekend of 01.07.12.
Night and day we pray earnestly for you, asking God to let us see you again to fill the gaps in your faith.
CedarCreek Mission Statement:: CedarCreek Church exists to help spiritually restless and unchurched people love Jesus, serve others, and tell the world about Christ.
1. At CedarCreek Church, we care about numbers because we know that there are individuals with powerful stories to share behind those numbers. Discuss the stories that you saw and share your own story.
2. There are some critics that think CedarCreek is just about bringing people to Christ, but not as attentive to helping people grow in their faith. Truth is, we are tenacious about helping people grow in their faith! What do we do as a church to encourage people to pursue a firm-rooted relationship with Christ?
5. Sometimes there can be a confusion between being obedient to gain God's favor (legalism) and obeying God out of love for Him. How can you know if you are being obedient to God out of desire to gain His favor or out of love and gratitude for Him?
6. Gratitude is the key to not just loving God, but staying in love with God. In fact, gratitude rehearses the blessings of God. How is it that practicing gratitude can have such a profound impact on increasing our love for God?
2. Missional Membership – this is for people who are serious about making a commitment to love Jesus with all of their hearts. Pick up a copy of the LivingItOut Bible study and start the Missional Membership process.
Click here to download a printable version of the message notes and discussion questions for the weekend of 01.01.12.
YOU WILL NEVER STAY COMMITTED IF YOU LIVE LOOKING B______________________________. LOOK FORWARD!
YOU WILL STAY COMMITTED WHEN YOU P_____________________ B___________________ IN THE OUTCOME!
YOU STAY COMMITTED WHEN YOU D____________________ T____________________ T____________________ THAT COMMITTED PEOPLE DO.
WHEN WE ARE PASSIONATELY COMMITTED T____________________________, WE CAN CHANGE THE WORLD!
M______________________________ IS THE HIGHEST LEVEL OF COMMITMENT AT CEDARCREEK CHURCH.
All Scripture is from the New Living Translation unless otherwise noted.
1 At the beginning of each year, most of us think about things that we want to change in our lives. What do you want to do differently this year? Why?
2 While a resolution and a commitment are related, they aren't the same thing. What is the difference between making a resolution to grow spiritually and making a commitment to grow spiritually?
3 If total commitment to Christ is the path that will lead us to the "win" in our spiritual lives, then why do so many of us stop short of being totally committed to living out their faith?
4 Spiritually speaking, how would you define a "win" for you this year? What kind of commitment would you need in order to achieve that win?
5 In Luke 14:25-27, Jesus lays out the picture of what it means to be totally committed to him. How would you rate your level of commitment to Christ? What do you need to do differently to increase your level of commitment this year?
6 One of the greatest things about CedarCreek Church is our passionate commitment to our mission statement. How have you been inspired or motivated as a result of some of the things we committed to doing together as a church?
7 Becoming a Missional Member of CedarCreek Church is a symbol of your total commitment to your faith as well as being a part of a group of individuals who are totally committed to their faith. Are you a Missional Member of CedarCreek? If not, why not?
Click here to download a printable version of the message notes and discussion questions for the weekend of 12.24.11.
What's So Holy About Christmas?
1. Consider the following statement: "Christmas is about Jesus, but Christmas is actually for us." Lee made that statement during the Christmas Eve message. How do you feel about that statement?
2. Read Philippians 2:7. In our celebrity-driven society, most of us like to see a show-stopping entrance. However, God came into the world in the human form by being born into it. Why did God come to earth as a baby? What difference does that make to us?
3. Do you believe that Jesus can relate to your struggles? As a human, Jesus endured the same difficulties we may face. How can you know that you can trust Christ to be there in tough times?
4. One of the reasons Jesus came is because he wanted to show us what God was like. He also wanted to show us what life should be like and how we can really live. What is the difference between living a "religious life" and the "full life" Jesus wants for us?
5. Read 1 John 4:9-10. Here is a simple, yet important question: "How can you know that God loves you?" Think about the Christmas Eve message and recall how you can be assured of God's love for you?
6. Read Romans 5:10-11. Christmas is God's gift to us, but an unused gift is a worthless gift. Share how you came to the point when you realized that you wanted to have a personal relationship with Jesus. If you haven't reached that point yet, discuss any reservations or questions you might have.
Click here to download a printable version of the message notes and discussion questions for the weekend of 12.17.11.
ICEBREAKER:Where is "home" for you this Christmas? Are you traveling somewhere or are others traveling to see you?
1 We've all been spiritually homeless because sin separated us from God. However, God sent Jesus from his heavenly home in order to provide a path for our return. Read Revelation 3:20. Talk about the ways you knew Jesus was "knocking on the door of your heart" and what made you decide to invite him into your heart.
2 During this weekend's message, Kyle talked about a story Jesus told in Matthew 7:24-27. What is the difference between the two homes that were built? Spiritually speaking, how can we know when we are building on the solid foundation of Christ or when we are building our faith on something that won't last?
3 Jesus knows a quiet, calm heart – a heart that is experiencing the depth of his love and peace. How can you "go deep" with God in order to experience that kind of calm and quiet in all circumstances?
4 One of the ways that we can show that Jesus is at home in our hearts is when we allow his love to shine through us toward others. Talk about all of the ways that we partner together at CedarCreek.tv to show Christ's love in our community. Which one of those ways inspires you to want to let Christ shine greater in your life?
5 IMPACT419 is a NW Ohio foodrive to help feed OUR hungry at a variety of local locations. Are you planning to be a part of IMPACT419? Discuss ways that you can be a part of this important project!
Click here to download a printable version of the message notes and discussion questions for the weekend of 12.10.11.
You We don't have a priest who is out of touch with our reality. He's been through weakness and testing, experienced it all—all but the sin. So let's walk right up to him and get what he is so ready to give. Take the mercy, accept the help.
…And while he was still a long way off…filled with love and compassion, he ran to his son, embraced him, and kissed him.
Titles and names for Jesus the Messiah.
1. As our "Wonderful Counselor" Jesus listens and guides us. He truly understands our human experience! Read 1 Peter 5:7. Discuss a time when you were facing a challenge in life but relied on Christ to lead and guide you through the difficult situation. How did you know you were being led by Christ in that situation?
3. Share a time when you relied on Jesus,"Almighty God," for the courage to share your spiritual journey or invite someone to church and then saw a tremendous turnaround in his or her life. You can even talk about how you have experienced Jesus as Almighty God in your life.
4 What are your spiritual gifts? (We ask this question a lot because it's important!) As you use your gifts, how do you know when it is Christ's power working through you rather than just you doing it on your own strength?
5 How have you experienced Jesus' care and provision in your life? As our Everlasting Father, Jesus says that he will provide and protect us. Are there any areas you need to turn over to Christ?
6 Not only is Jesus our Prince of Peace, but he calls us to take the peace that he gives into the world. How would you explain the peace that you have in Christ to someone who doesn't understand?
Click here to download a printable version of the message notes and discussion questions for the weekend of 12.03.11.
WHERE IS GOD WHEN THE WORLD IS COMING APART?
God Is R______________________________ the World to Himself.
God Is Reconciling the World through U_____________________.
God Is Planning a Huge P______________________________ for Us.
1. What are you looking forward to this Christmas season?
2. The title of the song, "Where are you Christmas?" feels like it could be the theme in many of your lives because life has been pretty tough lately – and the holiday season seems to magnify your difficulties. Is there something about this Christmas season you are dreading or not looking forward to? Our mission at CedarCreek.tv is to proclaim the that Good News of Jesus Christ to a lost and hurting world. List some of the ways that CedarCreek.tv is part of God's plan to reconcile the world through Jesus Christ. Now, list some of the ways that you've been personally involved with God's plan to reconcile the world to Himself.
4. You saw the story of Brad and Christine Kisabeth, CedarCreek.tv Missional Members who have been through tremendous difficulties. How were you inspired by their story?
5. Read Ephesians 1:9-10. When you think about the current circumstances of your life and how God sent Jesus Christ into the world to bring Good News to everyone, how can you better live out your faith even when your life is difficult?
Click here to download a printable version of the message notes and discussion questions for the weekend of 11.26.11.
1. What are the differences you sense between thankfulness and gratitude?
3. At what point(s) in your life would you say you experienced gratitude the most? What contributed to that? Are you aware of God's goodness in your life? Is God's goodness directly related to your current state of physical comfort and happiness?
4. Read John 7:36-50. What does this story teach us about gratitude? What is the evidence of gratitude demonstrated in this passage?
TASK: For the next two weeks set aside five to ten minutes to write down or recall out loud all the good things you noticed happened. Try to think of specific good moments, thoughts, scenes, people, gifts, etc. Prayerfully thank God for them all. Then close your time remembering Eucharist and take communion. You could do this alone or with people you do life with.
Click here to download a printable version of the message notes and discussion questions for the weekend of 11.19.11.
1. Matthew 5:3 tells us that when we reach the end of ourselves, that is when God is able to work in our lives most. Why is it that we tend to pay attention to God more when our lives fall apart versus of seeking Him when life is good?
2. Look at the other verses in this weekend's sermon notes. Choose a verse that stands out to you and talk about why you chose it.
3. In this weekend's message, Lee talked about four road blocks to humility (listed in this weekend's sermon notes). Are you struggling with any of those and how has that struggle kept you from wholly seeking God? How can you make it less of a stumbling block?
4. Rev. Run of Run DMC says that "chasing pleasure did not fill me" and that he gave up on chasing success when he "hit the top" and realized he was still empty. Is there anything wrong with wanting to be successful or make money? How can we know when our pursuit of success or money is going overboard?
5. There are some people who believe that if they only had (fill in the blank), then life would be great. Yet, God offers salvation – a gift that far outshines anything we could ever earn. Why do people underestimate God's plan and purpose for their lives and instead pursue money and/or success?
6. Adam Cufr shared the story of how one day he realized that the more he tried to fix his life on his own, the bigger mess he made. One day, Adam realized that he could no longer do life on his own. Have you ever had a time when you hit rock bottom and realized that the only place left to turn was God? What happened once you turned to Him?
7. After listening to this weekend's message, what have you been challenged to re-think or have you been challenged to make any changes to your life in order to humbly pursue God?
Click here to download a printable version of the message notes and discussion questions for the weekend of 11.12.11.
1. What relationship is causing the most difficulty in your life right now? What impact is that broken relationship having on your life?
2. This weekend, Lee used the story of porcupines to illustrate that while we need to have close human relationships, it's those very relationships that cause us the most pain. Often, we spend so much time looking at the other person's faults we don't recognize our own. What role have you played in that broken relationship?
3. The point of this weekend's message is to realize that forgiveness is the magic bullet when it comes to dealing with painful relationships. After listening to this weekend's message, how would you define "forgiveness?" Who needs to be involved in the forgiveness process and who doesn't need to be involved?
4. Reconciliation is the process of restoring a relationship. Whereas forgiveness only requires that the injured party let go of the offense, reconciliation requires both parties be willing to restore the relationship. Think back to this weekend's message. How can you know when a relationship is capable of being restored or when you just need to offer forgiveness and then walk away?
5. After listening to this weekend's message, is there a relationship or response that God is prompting you to deal with now? What do you need to do?


Or, Sign up for a Trove account Sign Up If you don't want to see the user tests again, sign up for an account it's free and only takes 2 minutes!
Your silence and actions have told me everything I need to know. I will always wonder what if? and all the why's why did it change? why then? why pick me and then do this?!
In 1886, during a strike at the McCormick Reaper plant in Chicago, a bomb exploded during the so-called Haymarket Riots, killing six policemen and wounding some 60 others. Eight people were indicted and four were later hanged for this incident.
Tya Tallieu. A7X ~ foREVer. Zacky Vengeance Synyster Gates Avenged Sevenfold Chula Animal Memes Music Quotes Alexandria Man Candy Heavy Metal. Zacky V. Oli Reaper. a7x. Zacky Vengeance Avenged Sevenfold Most Beautiful Man Man Candy Nice Things Heavy Metal Bands Heavy Metal Music Band. he's so gorgeous wow. Callan Hanley.


Welcome to It's THAT Podcast, episode 11! Where the kids talk about Jose Quintana, the Bears and the NFL Draft, as well as more of our favorite Internet things! We are on Apple Podcasts and the Google Play store, so give us a listen and a review (hopefully, favorable!) and thanks for listening and downloading!


Valentine's Day party-come one, come all! Whether single or in a relationship, Valentine's Day is the perfect occasion for a beautiful event. If you enjoy hosting great get-togethers, this is a great time to plan a soiree. What makes for a great party? The food, atmosphere and the music set the stage for a great event. Follow these great tips to succeed with a sophisticated, elegant and an inspiring event which is likely to illicit some real feelings of love.
To create a warm atmosphere use candlelight and low lighting. This is known to create an instant romantic glow. Keep your lights low and let the candle light dictate the mood. This is a great time to show case your beautiful candle ware or pick up some new items. Try some scented candles too, woodsy cinnamons are said to stir the passions.
The décor really depends on your personal taste. Whether you are more into a modern crisp look or whimsical flare, you can custom tailor to suit your objectives. Try to utilize some red roses, as we all know them to represent love. Make a playlist of some love songs or whatever mood you want to set. Whether you want everyone just chatting it up or getting up and dancing, you can set your vibe with the music list.
You can create seating room by moving tables against the wall to serve as the buffet tables for food and place chairs strategically to get people together. You can use tablecloths to prettify the table. This will give a crisp look. Don't over clutter the table with décor. You want the food to serve as the main décor. Fluff those pillows on your couch and create a special recluse for those who want to share a quiet moment.
Try some finger sandwiches cut into heart shapes with cookies cutter. A delicious option is also a chocolate or cheese fondue. This keeps guests meeting back at the table, a great way to keep things light and social. Keep plates of chocolate and those yummy heart shaped candies as part of your edible decor. Finger foods are a great option. Pick up or make your own H'orderves. Finger foods keep everyone mobile and able to socialize. Try some new recipes for dips and warm spreads.
Impress your guests with some delicious cocktails or a signature drink for the evening and give a snazzy name like cupids arrow or Love Potion No. 9. You can also pick up some sparkling wine or champagne and present them with strawberries. Make some delicious desserts as well. Pick up some pastries from the local bakery or make your own sweet treats.
Don't over calculate every detail. You set the stage, now let your guests have a great time and enjoy your party! Between the delicious food, the music, the romantic atmosphere and the cozy seating, your party is sure to be a hit!
Sit back relax and have a great evening!


The Los Angeles- and Oslo-based architect is collaborating with the South Shore Drill Team on We Know How To Order, a performance for the Chicago Architecture Biennial that responds to the geometry of Mies van der Rohe's Federal Plaza and the architecture of authority.
We Know How to Order will be performed on October 1, 2, and 3, 2015 in Federal Plaza. More information is available here.
Bryony Roberts has made site-specific installations and live interventions an important part of her ongoing practice, in each case inverting and activating the formal arrangements of existing architectural spaces as a way of engaging with them in a new light. In 2013, Roberts' project Inverting Neutra filled the void spaces of Richard Neutra's VDL Studio in Los Angeles with dense groups of hanging cords that rearranged the house's system of interlocking interior and exterior volumes.
Roberts sat down with architectural historian and critic Sylvia Lavin, who directs the M.A. and Ph.D. programs in architecture at UCLA.
Bryony Roberts: I'm really looking forward to hearing your thoughts on our project for the Biennial, and in general on the intersection between performance, preservation, and architecture. I'm collaborating with the South Shore Drill Team to do a site-specific performance at Mies's Federal Plaza, called We Know How To Order.
It's a live performance that will take place during the opening weekend in which forty young people from the South Side perform high-energy drill routines responding to the architecture. The piece is about different systems of order and what happens when they compound each other. The space of the Federal Plaza is highly ordered by the architecture and the systems of security — there is a Miesian grid that dictates everything from the pavers on the plaza to the building facades, and was later used to place lines of security bollards.
Its location within the downtown business district also reinforces its isolation from other urban activity. On the flip side, the South Shore Drill Team is a youth organization that trains people in highly disciplined, precise routines, which combine military movements with street choreography. Their goal is to use this structured program to keep kids away from violence on the streets. So I'm collaborating with the choreographer of the South Shore Drill team, Asher Waldron, to see how the two systems of order can be superimposed, with the drill routines transforming the lines of the Miesian grid into fast-paced movement.
I sought you out as a respondent because you've written extensively about intersections between art and architecture, and about what happens when mediums come together, specifically in Kissing Architecture.
Sylvia Lavin: I'm really struck by the fact that this is a federal building and we're in an era in which the issue of black bodies and the state is so prevalent. I'm going to assume that you have things to say about it. It seems to be one of the issues under some pressure in contemporary architecture and that already indicates the shift in the field from that moment to this one.
BR: Yes, that is a really important dimension of the piece. On the one hand, this piece is definitely about confronting the norms of the Federal Plaza, both its political and architectural norms. That space is a protected zone of Federal authority and an architectural landmark, so it holds expectations of non-threatening behavior to both political and architectural authority. In this project, the South Shore Drill Team remakes those conditions using their specific medium of choreography and drill routines. These are young people who are often made to feel unwelcome both in spaces of government and spaces of architectural prestige. But during this performance, they own that space and they're remaking it as new authors there.
So that political content is certainly there in the piece. But at the same time, I don't want this to be a one-liner political statement. That's in part why I didn't lead with that. I think it's richer if there are layers of how we use architecture and movement to structure bodies and those layers come out differently for each viewer as they are watching the piece.
That's what the title is about. It references a poem by Gwendolyn Brooks about African-American soldiers in WWII. In the voice of these soldiers, she describes how they were trained to order their behavior to assume the powerful and charismatic role of soldiers. But none of that training prepared them for the lonely moment of facing death, or the "lions in the air," as she calls it. That poem really struck me because these young people on the South Side are facing their own lions in the air — in gang violence, police brutality, random shootings — and the tools of discipline and order they are given only partially protect them from that lonely moment.
And finally, it's been interesting to notice how it's primarily white people who are asking for this piece to be more overtly political. The Drill Team certainly doesn't want that. They approach the politics of the South Side by training these kids to be successful students and performers and then giving them as many opportunities as possible to travel outside of their neighborhood. So the last thing they want is an aggressive political statement or a confrontation with the government that would threaten their political and financial network. When I talked to them about the politics of this piece, it was very clear that their goal was not an activist piece but rather something that would keep building the institutional structure that allows them to actually shift the politics of the neighborhood.
the space of the political and the space of the aesthetic. I think the issue on the table is whether that distinction holds true at all anymore, and whether or not the attachment to the distinction is an issue. You clearly think that they are different.
BR: No, I strongly believe they are not separate. I think the aesthetic and the political are completely bound up together.
What's compelling about both the architecture of the space and the Drill Team is that the aesthetics are so laden with military and political undertones. So in the Miesian space, this relentless grid creates a system of order and control. But that system goes to a point where it reaches a kind of"rationalist sublime," as Joan Ockman described when lecturing on Arne Jacobsen. That is particularly clear in the post office where the clear span space achieves many of the conventional qualities of the sublime — in its expansiveness beyond the scale of the individual. A similar thing happens with the South Shore Drill Team. They are performing military drills with rifles, so it's very explicitly about symbols of power and violence but they are twirling and flipping and dancing with these guns in a way that becomes celebratory and expressive. So it's not that the political and the aesthetic are separate; I'm just interested in how the aesthetic can take the political beyond its own assumptions.
BRYONY ROBERTS is the principal of the design and research practice Bryony Roberts Studio, based in Los Angeles and Oslo. She worked in the offices of WORKac and Mansilla + Tunon before founding her own practice in 2011. She has taught at Rice University School of Architecture in Houston and SCI-Arc in Los Angeles, and is now assistant professor at the Oslo School of Architecture.
SYLVIA LAVIN is an architectural historian and critic. She wrote Kissing Architecture (Princeton University Press, 2011), and curated the exhibition Everything Loose Will Land (The Graham Foundation, 2015) on architecture and visual arts in 1970s Los Angeles. She is currently director of the Critical Studies and M.A. and Ph.D. programs at UCLA.
This is an excerpt of a longer conversation, condensed and edited for clarity by Consortia. The full text of this conversation and many others will be featured in The State of the Art of Architecture, the catalogue of the first Chicago Architecture Biennial. The book will be published by Lars Müller Publishers in November 2015.