text:
International Lawyers Network Elects New Chair
April 03, 2020 (PRLEAP.COM) Business News
The International Lawyers Network, a global network of more than 5,000 lawyers, announced today that Pavla Kopeckova Prikrylova of PETERKA & PARTNERS in the Czech Republic, has been elected Chair of the ILN.
Kopeckova Prikrylova assumes the role from Simon Ekins, partner with Fladgate LLP, following an election by the Board of Directors in March. Ekins has served as ILN Chair since June of 2017, stepping down after three years of service.
Executive Director of the International Lawyers Network, Lindsay Griffiths, said "We are very grateful for the role that Simon played in chairing our Board of Directors over the last three years. His passion for the Network will be deeply missed. Simon has been an integral part of the ILN for 17 years, first as a member, then as a Director, and finally as our Chairman, and his engagement with the membership, love for the Network, and enthusiasm for driving it forward brought exceptional value to our membership."
Newly elected Kopeckova Prikrylova is a partner with PETERKA & PARTNERS, a CEE law firm, with nine offices. A member of the team since the creation of the firm, Kopeckova Prikrylova became a partner in 2001, and has strong experience in corporate/M&A, general commercial, real estate, and insolvency and restructuring matters. She assists clients on a broad range of business law matters on the Czech market, as well as within the markets of Central and Eastern Europe.
Kopeckova Prikrylova commented: "It is a great honour for me to have been proposed, and approved, as the new Chair of the ILN, an organisation in which our firm has been a member for 17 years. At the same time, I am very much aware of the fact that the times ahead of us will be challenging due to the world-changing global coronavirus pandemic.
The Board of Directors, the Executive Director, and I will do our best to lead the ILN safely through this difficult period and come out even stronger. I believe that more than ever before, the member firms will be able to benefit from the professionalism and relationships among us that we all share to well serve our clients and be competitive on today's globalised market."
"As we look to the future, we're fortunate to benefit from the caliber of proven industry and leadership experience that Pavla provides. We're well-positioned to continue to offer exceptional value to our member firms, and with Pavla's additional leadership, accelerate our work to be the leading provider of legal network services to our member firms," said Griffiths.
In addition to the Chair election, Directors' elections were held. Attilio Ferrari, Ferrari Pedeferri Boni Studio Legale Associato, Milan, Italy and Mitchell Karsch, Davis & Gilbert, New York, US were re-elected to their seats.
Directors Ziad Salloum, Salloum & Partners – Abu Dhabi; Henning von Lillienskjold, DAHL Law Firm – Denmark; Hernan Cordero, Cordero & Cordero – Costa Rica; Oliver Jankowsky, Hall & Wilcox – Australia; Bruce Feuchter, Stradling Yocca Carlson & Rauth – California; and Anad Krishnan, Anad & Noraini – Malaysia stepped down from their positions as Directors at the end of March. The ILN Administration and its members offered their sincere gratitude to the former Directors for their years of service.
About the ILN
The ILN is a non-exclusive network of high-quality mid-size law firms, which operates to create a global platform in the provision of legal services, particularly for clients with international needs. With a presence in 67 countries, it is exceptionally well placed to offer seamless legal services, often of a cross border nature from like-minded and quality legal practices. In 2016 and 2017, the ILN was shortlisted as Global Law Firm Network of the Year, and since 2011 has been listed as a Chambers & Partners Leading Law Firm Network. Today, the ILN remains at the very forefront of legal networks in its reach, capability and depth of expertise.
Lindsay Griffiths
International Lawyers Network
Email International Lawyers Network
Follow @lindsaygriffith
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\section{INTRODUCTION}\label{sec.intro}
Magnetic fields play an important role in stellar evolution. For low-mass stars, the magnetic field is believed to regulate stellar rotation from the early stages of star formation until the ultimate stages of the life of a star. In their youngest phases, the stellar magnetic field lines interact with accretion discs to prevent what would have been a rapid spin-up of the star, caused by accretion of material with high angular momentum and also the stellar contraction \citep[e.g.,][]{2013arXiv1309.7851B}. After the accretion phase is over and the disc has dissipated, the contraction of the star towards the zero-age-main sequence (ZAMS) provides an abrupt spin up. From that phase onwards, `isolated' stars (single stars and stars in multiple systems with negligible tidal interaction, such as the ones adopted in our sample) slowly spin down as they age \citep[e.g.][]{2013A&A...556A..36G}. This fact was first observed by \citet[][S72, from now on]{1972ApJ...171..565S}, who empirically determined that the projected rotational velocities  $v \sin(i)$ of G-type stars in the main-sequence (MS) phase decrease with age $t$ as $v\sin(i) \propto t^{-1/2}$. This relation, called the ``Skumanich law'', serves as the basis of the gyrochoronology method \citep{2003ApJ...586..464B}, which yields age estimates based on rotation measurements. The rotational braking observed by \citetalias{1972ApJ...171..565S} is believed to be caused by stellar winds, which, outflowing along magnetic field lines, are able to efficiently remove the angular momentum of the star \citep[e.g.,][]{1958ApJ...128..664P,1962AnAp...25...18S,1967ApJ...148..217W}.

Indicators of magnetic activity, such as surface spot coverage, emission from the chromosphere, transition region or corona, have been recognised to be closely linked to rotation \citep[e.g., S72;][]{1984A&A...133..117V,1984ApJ...279..763N,1997JGR...102.1641A,2007LRSP....4....3G,2012A&A...546A.117G,2012LRSP....9....1R}. However, the magnetic activity-rotation relation breaks for rapidly rotating stars, where the indicators of stellar magnetism saturate and become independent of  rotation. A saturation of the dynamo operating inside the star, inhibiting the increase of magnetism with rotation rate, has been attributed to explain the activity saturation observed in low-period stars \citep{1984A&A...133..117V}, but alternative explanations also exist \citep[e.g.,][]{1991ApJ...376..204M,1999A&A...346..883J,2007A&A...473..501A}.

The average unsigned surface magnetic field $\langle |B_I| \rangle$, as measured by Zeeman-induced line broadening of unpolarised light (Stokes I), also correlates with rotation, in a similar way as the indicators of magnetic activity do (i.e., as one goes towards faster rotating stars, $\langle |B_I| \rangle$ increases until it reaches a saturation plateau; \citealt{2009ApJ...692..538R}). Because $\langle |B_I| \rangle$ is the product of the intensity-weighted surface filling factor of active regions $f$ and the mean unsigned field strength in the regions $B_I$ ($\langle |B_I| \rangle=fB_I$), it is still debatable whether the saturation occurs in the filling factor $f$ of magnetically active regions or in the stellar magnetism itself or in both \citep{1994ASPC...64..477S,1996IAUS..176..237S,2001ASPC..223..292S,2009ApJ...692..538R}.

Although Zeeman broadening yields estimates of the average of the total (small and large scales) unsigned surface field strength,  it does not provide information on the magnetic topology \citep{2013AN....334...48M}. For that, a complementary magnetic field characterisation technique, namely Zeeman-Doppler Imaging \citep[ZDI, e.g.,][]{1997A&A...326.1135D}, should be employed. The ZDI technique consists of analysing a series of circularly polarised spectra (Stokes V signatures) to recover information about the large-scale magnetic field (its intensity and orientation). In this work, we take advantage of the increasing number of stars with surface magnetic fields mapped through the ZDI technique and investigate how their large-scale surface magnetism varies with age, rotation and X-ray luminosity (an activity index). In the past decade,  ZDI  has been used to reconstruct the topology and intensity of the surface magnetic fields of roughly one hundred stars \citep[for a recent review of the survey, see][]{2009ARA&A..47..333D}. Since the ZDI technique measures the magnetic flux averaged over surface elements, regions of opposite magnetic polarity within the element resolution cancel each other out \citep{2010MNRAS.404..101J,2011MNRAS.410.2472A}. As a consequence, the ZDI magnetic maps are limited to measuring large-scale magnetic field.

Because the small-scale field decays faster with height above the stellar surface than the large-scale field \citep[e.g.,][]{2014MNRAS.439.2122L}, only the latter permeates the stellar wind. If indeed magnetised stellar winds are the main mechanism of removing angular momentum from the star in the MS phase, one should expect the large-scale field to correlate with rotation and age. Likewise, a correlation between rotation and magnetism should also be expected if rotation is the driver of stellar magnetism through dynamo field generation processes. The interaction between magnetism, rotation and age is certainly complex and empirical relations, such as the ones derived in this work, provide important constraints for studies of rotational evolution and stellar dynamos.

This paper is organised as follows. We present our sample of stars in Section~\ref{sec.sample}. Section~\ref{sec.relations} shows the empirically-derived trends with magnetism we find within our data. In Section~\ref{sec.discussion}, we discuss how the results obtained using the Zeeman broadening technique compare to the ones derived from Zeeman-Doppler Imaging (Section~\ref{sec.comparison}), we investigate the presence of saturation in the large-scale field  (\ref{sec.saturation}),  analyse whether stars hosting hot-Jupiters present different magnetism compared to stars lacking hot-Jupiters (\ref{sec.hjhosts}) and discuss the trends obtained for the pre-main sequence (PMS) accreting stars (\ref{sec.accreting}). In Section~\ref{sec.magnetochronology}, we discuss the impact of our findings as a new way to assess stellar ages and as a valuable observational input for dynamo studies and stellar mass loss evolution. Our summary and conclusions are presented in Section~\ref{sec.conclusions}.

\section{The sample of stars}\label{sec.sample}
The stars considered in this study consist of $73$ late-F, G, K, and M dwarf stars, in the PMS to MS phases. All have had their large-scale surface magnetic fields reconstructed using the ZDI technique, with some having been observed at multiple epochs, as listed in Table~\ref{table}. The magnetic maps, $104$ in total, have either been published elsewhere \citep{1999MNRAS.302..437D,2003MNRAS.345.1145D,2008MNRAS.390..545D,2008MNRAS.385.1179D,2008MNRAS.386.1234D,2010MNRAS.409.1347D,2010MNRAS.402.1426D,2011MNRAS.412.2454D,2011MNRAS.417..472D,2011MNRAS.417.1747D,2012MNRAS.425.2948D,2013MNRAS.436..881D, 2006MNRAS.370..468M,2011MNRAS.413.1922M,2007MNRAS.374L..42C,2008MNRAS.384...77M,2008MNRAS.390..567M,2010MNRAS.407.2269M,2008MNRAS.388...80P,2009A_A...508L...9P,2009MNRAS.398..189H,2009MNRAS.398.1383F,2010MNRAS.406..409F,2012MNRAS.423.1006F,2013MNRAS.435.1451F,2011AN....332..866M,2012A_A...540A.138M,2011MNRAS.413.1949W,2013arXiv1310.7620D} or are in process of being published (Folsom et al.~2014 in prep, Petit et al.~2014 in prep, Waite et al.~2014 in prep). Although the reconstructed maps provide the distribution of magnetic fields at the stellar surface, in this paper we only use the unsigned average field strengths $\langle |B_V| \rangle$ (i.e., integrated over the surface of the star).\footnote{In order to differentiate between field strengths derived from Stokes V measurements (ZDI) and from Stokes I (Zeeman broadening), we use the indices $V$ and $I$, respectively.} In the present work, $\langle |B_V| \rangle$ is calculated based on the radial component of the observed surface field, as we are mainly interested in the field associated with the stellar wind \citep{2013MNRAS.431..528J}. We also consider the Sun in our dataset. For the solar magnetic field, we use the magnetograms from NSO - Kitt Peak data archive at solar maximum and minimum (Carrington rotations CR1851 and CR1907, respectively). To allow a direct comparison of the solar and stellar magnetic fields, we restrict the reconstruction of the solar surface fields to a maximum order of $l_{\rm max} =3$ of the spherical harmonic expansion (note, for instance, that modes with $l \lesssim 3$ already contain the bulk of the  total photospheric magnetic energy in solar-type stars, \citealt{2008MNRAS.388...80P}).

Table~\ref{table} lists the general characteristics of the stars considered here, including quantities such as age $t$ (whenever available), rotation period $P_{\rm rot}$, $\langle |B_V| \rangle$, Rossby number Ro, X-ray luminosity $L_X$ and $L_X/L_{\rm bol}$, where $L_{\rm bol}$ is the bolometric luminosity. The measurement errors associated with these quantities are described in Appendix~\ref{ap.sample}. Among the $73$ stars in our sample, $61$ objects have age estimates (totaling $90$ maps), which were collected from the literature and are based on different methods. For the PMS accreting stars, ages were derived using the stellar evolution models of \citet{2000A_A...358..593S}, as derived in \citet{2012ApJ...755...97G} and \citet{2013MNRAS.436..881D}. For the remaining stars, methods used for deriving ages include, for example, isochrones, lithium abundance, kinematic convergent point, gyrochronology, chromospheric activity. Note also that some of the stars in our sample are members of associations and open clusters and have, therefore, a reasonably well-constrained age (often derived with multiple methods). The last column of Table~\ref{table} lists the references for all the values adopted in this paper. In particular, the references from which ages were obtained are presented in boldface.

\begin{table*}
\centering
\caption{The objects in our sample. Columns are: star name, spectral type, mass, radius, rotation period, Rossby number, age, X-ray luminosity, X-ray-to-bolometric luminosity ratio, average large-scale unsigned surface magnetic field and its observation epoch (year and month). The measurement errors associated with these quantities are described in Appendix~\ref{ap.sample}. References for the values compiled in this table are shown in the last column. In boldface are the references from which the ages adopted in this paper were obtained. \label{table}}
\begin{tabular}{llccccccccccccccccc}
\hline
Star	&	Sp.		&	$	M_\star 	$	&	$	R_\star		$	&	$	P_{\rm rot}		$	&	$	\rm Ro		$	&	age & $\log\left[\frac{L_X}{\rm erg/s}\right]$ &$\log\left[\frac{L_X}{L_{\rm bol}}\right]$& $	\langle |B_V| \rangle		$	 &  Obs.& Ref. \\
ID     &	Type &	$(M_\odot)	$	&	$(R_\odot)	$	&(d)&  & (Myr)& & &$	(G)	$ & epoch&  &
\input{latex_table_a.tex}
\hline
\end{tabular}
\\

\citetalias{Petit2014}          : Petit et al.~(2014) in prep.;
\citetalias{2013arXiv1311.3374M}: \citet{2013arXiv1311.3374M};
\citetalias{2011A_A...530A..73C}: \citet{2011A_A...530A..73C};
\citetalias{2006ARep...50..579K}: \citet{2006ARep...50..579K};
\citetalias{2013arXiv1310.7620D}: \citet{2013arXiv1310.7620D};
\citetalias{2010ApJ...714..384R}: \citet{2010ApJ...714..384R};
\citetalias{2012ApJ...753...76W}: \citet{2012ApJ...753...76W};
\citetalias{2008A_A...488..771J}: \citet{2008A_A...488..771J};
\citetalias{2003AJ....125.1980K}: \citet{2003AJ....125.1980K};
\citetalias{2011ApJ...743...48W}: \citet{2011ApJ...743...48W};
\citetalias{2009ApJ...698.1068P}: \citet{2009ApJ...698.1068P};
\citetalias{2007Ap.....50..187B}: \citet{2007Ap.....50..187B};
\citetalias{2008MNRAS.388...80P}: \citet{2008MNRAS.388...80P};
\citetalias{2003A_A...397..147P}: \citet{2003A_A...397..147P};
\citetalias{2011AN....332..866M}: \citet{2011AN....332..866M};
\citetalias{2012NewA...17..537X}: \citet{2012NewA...17..537X};
\citetalias{2012A_A...540A.138M}: \citet{2012A_A...540A.138M};
\citetalias{2009IAUS..258..395G}: \citet{2009IAUS..258..395G};
\citetalias{2001A_A...379..279Q}: \citet{2001A_A...379..279Q};
\citetalias{2009A_A...501..941H}: \citet{2009A_A...501..941H};
\citetalias{2003A_A...397..987C}: \citet{2003A_A...397..987C};
\citetalias{2004A_A...417..651S}: \citet{2004A_A...417..651S};
\citetalias{2009A_A...508L...9P}: \citet{2009A_A...508L...9P};
\citetalias{2002ApJ...574..412W}: \citet{2002ApJ...574..412W};
\citetalias{2008ApJ...687.1264M}: \citet{2008ApJ...687.1264M};
\citetalias{2013A_A...556A..53E}: \citet{2013A_A...556A..53E};
\citetalias{Folsom2014}         : Folsom et al.~(2014) in prep.;
\citetalias{2008hsf2.book..757T}: \citet{2008hsf2.book..757T};
\citetalias{Waite2014}          : Waite et al.~(2014) in prep.;
\citetalias{2011PASA...28..323W}: \citet{2011PASA...28..323W};
\citetalias{2011A_A...532A..10M}: \citet{2011A_A...532A..10M};
\citetalias{2008ApJ...689.1127M}: \citet{2008ApJ...689.1127M}
\end{table*}
\begin{table*}
\centering
\contcaption{The objects in our sample.}
\begin{tabular}{llccccccccccccccccc}
\hline
Star	&	Sp.		&	$	M_\star 	$	&	$	R_\star		$	&	$	P_{\rm rot}		$	&	$	\rm Ro		$	&	age & $\log\left[\frac{L_X}{\rm erg/s}\right]$ &$\log\left[\frac{L_X}{L_{\rm bol}}\right]$& $	\langle |B_V| \rangle		$	 &  Obs.& Ref. \\
ID     &	Type &	$(M_\odot)	$	&	$(R_\odot)	$	&(d)&  & (Myr)& & &$	(G)	$ & epoch&  &
\input{latex_table_b.tex}
\hline
\end{tabular}
\\

\citetalias{1995A_A...302..775G}: \citet{1995A_A...302..775G};
\citetalias{1999MNRAS.302..437D}: \citet{1999MNRAS.302..437D};
\citetalias{2009A_ARv..17..251S}: \citet{2009A_ARv..17..251S};
\citetalias{2011MNRAS.410.2472A}: \citet{2011MNRAS.410.2472A};
\citetalias{2013ApJ...766....6B}: \citet{2013ApJ...766....6B};
\citetalias{2005ApJ...628L..69L}: \citet{2005ApJ...628L..69L};
\citetalias{2011MNRAS.413.1949W}: \citet{2011MNRAS.413.1949W};
\citetalias{2011MNRAS.413.1922M}: \citet{2011MNRAS.413.1922M};
\citetalias{2006MNRAS.370..468M}: \citet{2006MNRAS.370..468M};
\citetalias{2003A_A...411..595S}: \citet{2003A_A...411..595S};
\citetalias{2003A_A...399..983W}: \citet{2003A_A...399..983W};
\citetalias{1998ApJ...499L.199S}: \citet{1998ApJ...499L.199S};
\citetalias{2003A_A...410..671M}: \citet{2003A_A...410..671M};
\citetalias{2014MNRAS.438L..11B}: \citet{2014MNRAS.438L..11B};
\citetalias{2003MNRAS.345.1145D}: \citet{2003MNRAS.345.1145D};
\citetalias{2004A_A...417.1047K}: \citet{2004A_A...417.1047K};
\citetalias{2004ApJ...614..386B}: \citet{2004ApJ...614..386B};
\citetalias{2009MNRAS.398.1383F}: \citet{2009MNRAS.398.1383F};
\citetalias{2013MNRAS.435.1451F}: \citet{2013MNRAS.435.1451F};
\citetalias{2005A_A...443..609S}: \citet{2005A_A...443..609S};
\citetalias{2010A_A...515A..98P}: \citet{2010A_A...515A..98P};
\citetalias{2008MNRAS.385.1179D}: \citet{2008MNRAS.385.1179D};
\citetalias{2007MNRAS.374L..42C}: \citet{2007MNRAS.374L..42C};
\citetalias{2008ApJ...687.1339K}: \citet{2008ApJ...687.1339K};
\citetalias{2003A_A...407..679U}: \citet{2003A_A...407..679U};
\citetalias{2006ApJ...648..683G}: \citet{2006ApJ...648..683G};
\citetalias{2012MNRAS.423.1006F}: \citet{2012MNRAS.423.1006F};
\citetalias{2010MNRAS.406..409F}: \citet{2010MNRAS.406..409F};
\citetalias{2006A_A...460..251M}: \citet{2006A_A...460..251M};
\citetalias{2008MNRAS.390..545D}: \citet{2008MNRAS.390..545D};
\citetalias{2014MNRAS.438.1162V}: \citet{2014MNRAS.438.1162V};
\citetalias{2008MNRAS.390..567M}: \citet{2008MNRAS.390..567M};
\citetalias{2010MNRAS.407.2269M}: \citet{2010MNRAS.407.2269M};
\citetalias{1995ApJ...450..392S}: \citet{1995ApJ...450..392S};
\citetalias{2008MNRAS.384...77M}: \citet{2008MNRAS.384...77M};
\citetalias{2000ApJ...528..537P}: \citet{2000ApJ...528..537P};
\citetalias{2010NatGe...3..637B}: \citet{2010NatGe...3..637B};
\citetalias{2010MNRAS.409.1347D}: \citet{2010MNRAS.409.1347D};
\citetalias{2014MNRAS.437.3202J}: \citet{2014MNRAS.437.3202J};
\citetalias{2000A_A...358..593S}: \citet{2000A_A...358..593S};
\citetalias{2012ApJ...755...97G}: \citet{2012ApJ...755...97G};
\citetalias{2007A_A...468..353G}: \citet{2007A_A...468..353G};
\citetalias{2008MNRAS.386.1234D}: \citet{2008MNRAS.386.1234D};
\citetalias{2009MNRAS.398..189H}: \citet{2009MNRAS.398..189H};
\citetalias{2011AJ....141..127I}: \citet{2011AJ....141..127I};
\citetalias{1993ApJ...416..623F}: \citet{1993ApJ...416..623F};
\citetalias{2013MNRAS.436..881D}: \citet{2013MNRAS.436..881D};
\citetalias{2012MNRAS.425.2948D}: \citet{2012MNRAS.425.2948D};
\citetalias{2010A_A...519A.113G}: \citet{2010A_A...519A.113G};
\citetalias{2011MNRAS.417..472D}: \citet{2011MNRAS.417..472D};
\citetalias{2011MNRAS.412.2454D}: \citet{2011MNRAS.412.2454D};
\citetalias{2011A_A...530A...1A}: \citet{2011A_A...530A...1A};
\citetalias{2010MNRAS.402.1426D}: \citet{2010MNRAS.402.1426D};
\citetalias{2010A_A...519A..34P}: \citet{2010A_A...519A..34P};
\citetalias{2011MNRAS.417.1747D}: \citet{2011MNRAS.417.1747D};
\citetalias{2012ApJ...747..142S}: \citet{2012ApJ...747..142S}

\end{table*}

In order to investigate possible correlations in our data, we perform power-law fits of any two quantities $x=\log(X)$ and $y=\log(Y)$ (fitted through linear least-squares fits to logarithms), such that $y = q +p x$ (or $Y=10^q X^p)$, with $q$ and $p$ being the coefficients derived in the linear regression. These regressions were obtained using the bisector ordinary least-squares method \citep{1990ApJ...364..104I}, which treats the $x$ and $y$ variables symmetrically  \citep{basu}. We opted such a fitting method because, for the quantities analysed here, the functional dependences of $x$ and $y$ are not clear.

Before we present the analyses of the trends with magnetism, it is useful to compare how our data relate to the Skumanich law, where rotation period $P_{\rm rot}$ is related to age as $P_{\rm rot} \propto t^{1/2}$ or $t \propto P_{\rm rot}^2 $ (see~Figure~\ref{fig.prot_age}). The  power-law indices $p$ obtained for the non-accreting (solid line) and accreting (dashed line) stars are shown in Table~\ref{tab.powerlaw}, along with the Spearman's rank correlation coefficient $\rho$ and its probability under the null hypothesis (i.e., uncorrelated quantities). For the non-accreting stars, we find that {$t \propto P_{\rm rot}^{1.96 \pm 0.15 }$ ($\rho=0.76$)}, which is consistent with the Skumanich law. Note that the accreting stars (green points) follow a different behaviour to the remaining objects in our sample and, because of that, we treat them as a different population throughout this paper. The physics of accreting stars is more complex than that of the disc-less stars, as the former interact with their accretion discs through stellar magnetic field lines that thread their discs (for a recent review see \citealt{2013arXiv1309.7851B} and references therein). As a consequence, the presence of the disc controls the rotation of these stars \citep{2007ApJ...671..605C}. In addition, the young PMS stars will continue to contract once the disc has dispersed and, consequently, will spin up, while evolving towards the ZAMS. Because not enough time has passed since their formation from the gravitational collapse of their natal molecular clouds, they still have imprinted on them the initial conditions of their rotation and, therefore, possess a large spread in the $P_{\rm rot}$-$t$ diagram.

\begin{figure}
\includegraphics[width=80mm]{legend-page1.pdf
\caption{Correlation between age $t$ and rotation period $P_{\rm rot}$ for the stars in our sample, indicating that the non-accreting stars follow the Skumanich law ($t \propto P_{\rm rot}^{2}$). The solid (dashed) line is a power-law fit to our sample of non-accreting (accreting) objects. A typical error bar is indicated in grey (also in Figures~\ref{fig.B_age} to \ref{fig.ap2}).\label{fig.prot_age}}
\end{figure}

\begin{table*}
\centering
\caption{Power-law indices ($Y\propto X^p$) computed using the bisector linear least-squares method, fitted to logarithms. The Spearman's rank correlation coefficient $\rho$ and its probability under the null hypothesis are also shown. Fits considering only non-accreting F, G, K and early-M dwarf stars, only PMS accreting stars and all the data in our sample are shown separately.
\label{tab.powerlaw}}
\begin{tabular}{llrrcrrcrrcccccc}
\hline
&&\multicolumn{3}{c}{Fits for dwarf stars only} &\multicolumn{3}{c}{Fits for accreting stars only} &\multicolumn{3}{c}{Fits considering all the sample}  \\ \hline
$Y$ & $X$ & $\rho$ & Prob. & $p$ & $\rho$  & Prob.  &  $p$ & $\rho$ & Prob. & $p$\\
&&& (\%)&&&(\%)&&&(\%) \\
\hline
\input{fit_bisector_table_for_paper.tex}
\hline
\end{tabular}
\\$^a$ Fits considering only points with $\rm Ro \gtrsim 0.1$ (cf.~\S\ref{sec.comparison}).
\end{table*}

\section{Trends with magnetism}\label{sec.relations}
In this Section, we investigate possible trends between the following quantities:  $\langle |B_V| \rangle$,  $t$, $P_{\rm rot}$,  \rm Ro , $L_X$, $L_X/L_{\rm bol}$ and unsigned magnetic flux $\Phi_V$. Table \ref{tab.powerlaw} summarises the results of our fits. {It is worth noting that, when analysed individually, each subset of objects (as presented in Table~\ref{table}) do not show correlations with high statistical significance due to their narrow range of parameters (e.g., ages, rotation periods). However, trends are more robust when the different subsets are combined together and the dynamic range increases.} For the non-accreting stars, all the relations have high statistical significance, with usually large Spearman's rank correlation coefficients and low probabilities of there not being correlations ($< 0.01$ \%). On the other hand, the relations we derive for the accreting stars are significantly poorer, with $|\rho | \lesssim 0.6$ and usually high probabilities of these quantities not being correlated, except for $\Phi_V$ versus $P_{\rm rot}$. The poorer fits are a result of the narrower range of parameters of this subset and also due to its relatively small number of data points ($11$ stars and $16$ magnetic maps). These objects will be discussed in more detail in Section~\ref{sec.ttauri}.  Next, we discuss a few selected trends for the non-accreting population.

\subsection{Non-accreting stars}
\subsubsection{Correlation with age}
In his seminal paper, \citetalias{1972ApJ...171..565S} predicted that magnetic fields decay as the inverse square of age, based on the age-rotation relation and further assuming that surface fields have a linear dependence with the rotation of the star (cf.~Section~\ref{subsec.prot-B}). In order to test this prediction, we show in Figure~\ref{fig.B_age} the trend we find between $\langle |B_V| \rangle$ and $t$ for the stars in our sample. The correlation we found holds for more than two orders of magnitude in $\langle |B_V| \rangle$ and three orders of magnitude in $t$ for the non-accreting stars. From our power-law fit (solid line), we find that $\langle |B_V| \rangle \propto t^{-0.655 \pm 0.045}$, which has a similar age-dependence as the Skumanich law ($\Omega_\star \propto t^{-0.5}$) and supports the magnetism-age prediction inferred by \citetalias{1972ApJ...171..565S} that there is magnetic field decay as the inverse square-root of age. A similar power-law dependence is found between the unsigned surface flux $\Phi_V= \langle |B_V| \rangle 4 \pi R_\star^2$ and age ($\Phi_V \propto t^{-0.622\pm 0.042}$).

\begin{figure}
\includegraphics[width=80mm]{legend-page2.pdf
\caption{Correlation between the average large-scale field strength derived from the ZDI technique $\langle |B_V| \rangle$ and age $t$, for the non-accreting stars in our sample. The trend found (solid line) has a similar age dependence as the Skumanich law ($\Omega_\star \propto t^{-0.5}$). This relation could be used as an alternative method to estimate the age of stars (``magnetochronology''). \label{fig.B_age}}
\end{figure}

\subsubsection{Correlation with rotation period}\label{subsec.prot-B}
Stellar winds are believed to regulate the rotation of MS stars. The empirical Skumanich law, for example, can be theoretically explained using a simplified stellar wind model \citep{1967ApJ...148..217W}, if one assumes that the stellar magnetic field scales linearly with the rotation rate of the star $\Omega_\star$. To investigate whether our data support the presence of such a linear-type dynamo  ($B \propto \Omega_\star \propto P_{\rm rot}^{-1}$), we present how $\langle |B_V| \rangle$ scales with $P_{\rm rot}$  in Figure~\ref{fig.b_prot}. Our results show that {$\langle |B_V| \rangle \propto P_{\rm rot}^{-1.32 \pm 0.14}$ ($|\rho|=0.54$)}, indicating that our data  supports a linear-type dynamo of the large-scale field within {$3\sigma$}. A similar nearly linear trend is found between the unsigned surface flux $\Phi_V$ and $P_{\rm rot}$, with a larger correlation coefficient {$|\rho|=0.72$}.

Although the correlation between $\langle |B_V| \rangle$ and $P_{\rm rot}$ indeed exists (with a negligible null-probability), this relation has a significant spread. One possible explanation for this spread could be that in the Weber-Davis theory of stellar winds, a very simplistic field geometry is assumed (a split monopole) with the entire surface of the star contributing to wind launching. However, the complexity of the magnetic field topology can play an important role in the rotational evolution of the star \citep[e.g.,][]{2009ApJ...703.1734V,2012MNRAS.423.3285V,2010ApJ...721...80C}. ZDI observations have shown that stellar magnetic field topologies can be much more complex than that of a split monopole. In addition, numerical simulations of stellar winds show that part of the large-scale surface field should consist of closed field lines, which do not contribute to angular momentum removal \citep[e.g.,][]{2014MNRAS.438.1162V}. The large spread in the $\langle |B_V| \rangle$-$P_{\rm rot}$ relation could therefore be explained by the differences in magnetic field topologies present in the stars of our sample.

\begin{figure}
\includegraphics[width=80mm]{legend-page3.pdf
\caption{Correlation between the average large-scale field strength derived from the ZDI technique $\langle |B_V| \rangle$ and rotation period $P_{\rm rot}$, for the non-accreting stars in our sample. Our data support the presence of a linear-type dynamo for the large-scale field (i.e., $\langle |B_V| \rangle \propto \Omega_\star \propto P_{\rm rot}^{-1}$) within {$3\sigma$}, although a large scatter exists. The open symbols (not considered in the fit) are saturated M dwarf stars without age estimates: blue squares for $M_\star \geq 0.4~M_\odot$ (early Ms), green circles for $0.2 < M_\star/M_\odot < 0.4$ (mid Ms) and red circles for $M_\star \leq 0.2~M_\odot$ (late Ms). The dotted line, at an arbitrary vertical offset, is indicative of the slope found from ZB measurements between $\langle |B_I| \rangle$ and $P_{\rm rot}$ \citep{1996IAUS..176..237S}.
\label{fig.b_prot}}
\end{figure}

\subsubsection{Correlation with Rossby number}
Another possibility for the spread found in the relation between $\langle |B_V| \rangle$ and $P_{\rm rot}$ can be due to the fact that we are considering a broad range of spectral types. Traditionally, the use of Rossby number (\rm Ro) instead of $P_{\rm rot}$ allows comparison across different spectral types, reducing the spread commonly noticed in trends involving $P_{\rm rot}$. \rm Ro\ is defined as the ratio between $P_{\rm rot}$ and convective turnover time $\tau_c$. To calculate \rm Ro\ for the non-accreting stars, we used the theoretical determinations of $\tau_c$ from \citet{2010A&A...510A..46L}. Appendix \ref{ap.rossby} shows how our results vary if we adopt different approaches for the calculation of $\tau_c$. For the {$8$} stars that have masses outside the mass interval  for which $\tau_c$ was computed  in \citet[][$0.6 \leq M_\star/M_\odot \leq 1.2$]{2010A&A...510A..46L}, we adopt the following approximation. Stars with a given age t and mass $M_\star \leq 0.6M_\odot$ were assumed to have $\tau_c=\tau_c(M_\star=0.6M_\odot, t)$ and for  $M_\star \geq 1.2 M_\odot$ were assumed to have $\tau_c=\tau_c(M_\star=1.2 M_\odot, t)$. As a result, for the former (latter) group, the calculated $\tau_c$ is a lower (upper) limit, while \rm Ro\ is an upper (lower) limit. In this work, we do not assign errors to Rossby numbers, but we note that these values are model-dependent. For the accreting stars, \rm Ro\ was derived from an update to the models of \citet{1996ApJ...457..340K}, as detailed by \citet{2012ApJ...755...97G}.

In general, all our fits against \rm Ro\ have larger unsigned Spearman's rank correlation coefficients than fits against $P_{\rm rot}$. Figure~\ref{fig.b_rossby}a shows $\langle |B_V| \rangle$ as a function of \rm Ro, where we find that {$\langle |B_V| \rangle \propto \rm Ro^{-1.38\pm0.14}$}. This relation will be further discussed later on Section~\ref{sec.comparison}.  Additionally, we found a similar power-law dependence between the magnetic flux $\Phi_V$ and \rm Ro\ (Figure~\ref{fig.b_rossby}b):  {$\Phi_V \propto \rm Ro^{-1.19\pm0.14}$}. Right/left arrows in Figure~\ref{fig.b_rossby} denote the cases with lower/upper limits of \rm Ro.

We note that the correlation between $\langle |B_V| \rangle$ and $\rm Ro$ indeed has less scatter than that between $\langle |B_V| \rangle$ and $P_{\rm rot}$  shown in Figure~\ref{fig.b_prot}.  In spite of the tighter correlation, a noticeable scatter still exists, which, as discussed in Section~\ref{subsec.prot-B}, could be caused by different field topologies. It is also worth noting that the field topology and intensity can change over a stellar magnetic cycle and this fact alone can also be a source of scatter in our relations (although it is possibly not the dominant source).  For the large-scale field of the Sun, a variation of a factor of $\sim 2$ in $\langle |B_V| \rangle$ is observed between the two maps used in this work, when the Sun changed to a simplified, large-scale dipolar topology at solar minimum (CR 1907) from a more complex one at maximum (CR 1851). For stars like HD~190711, the variation of $\langle |B_V| \rangle$ among the maps considered in this study is almost a factor of $3$.

\begin{figure}
\includegraphics[width=80mm]{legend-page4.pdf}\\%5_B_rossby_landin}\\
\includegraphics[width=80mm]{legend-page5.pdf
\caption{(a) Correlation between the average large-scale field strength derived from the ZDI technique $\langle |B_V| \rangle$ and Rossby number \rm Ro, for the non-accreting stars in our sample. Using Stokes I data, \citet{2009ApJ...692..538R} showed that  $\langle |B_I| \rangle$ saturates for $\rm Ro \lesssim 0.1$. \citet{2008MNRAS.390..545D} suggested that there might be two different levels of saturation (dashed lines) among the low-mass stars, caused by different efficiencies at producing large- and small-scale fields. (b) Same as in (a), but now considering the magnetic flux $\Phi_V$. Note that the bi-modality in the saturation level is removed if $\Phi_V$ is considered instead of $\langle |B_V| \rangle$. Open symbols are as in Figure \ref{fig.b_prot}. Solid lines show power-law fits considering objects with $\rm Ro\gtrsim 0.1$. The dotted line (arbitrary vertical offset) in the upper panel is indicative of the slope found from ZB measurements between $\langle |B_I| \rangle$ and \rm Ro\ \citep{2001ASPC..223..292S}. \label{fig.b_rossby}}
\end{figure}

\subsubsection{Correlations with X-ray luminosity}
Another interesting trend we found in our data is between the X-ray luminosity $L_X$ and $\Phi_V$ (Figure~\ref{fig.Lx_flux}). For the non-accreting stars we found that {$L_X \propto \Phi_V^{1.80 \pm 0.20}$}.  If we include the accreting objects, the slope between $L_X$ and $\Phi_V$ flattens and we find that {$L_X^{\rm (all)} \propto \Phi_V^{0.913 \pm 0.054}$} (fit not shown in Figure~\ref{fig.Lx_flux}).

\begin{figure}
\includegraphics[width=80mm]{legend-page6.pdf
\caption{Correlation between X-ray luminosity $L_X$ and large-scale magnetic flux ($\Phi_V=4\pi R_\star^2 \langle |B_V| \rangle$) derived from the ZDI technique for the non-accreting stars in our sample. The open symbols are as in Figure~\ref{fig.b_prot} and were not considered in the fit (solid line). The dotted line, at an arbitrary vertical offset, is indicative of the slope found from ZB measurements for dwarf stars between $L_X$ and $\Phi_I = \langle |B_I| \rangle 4 \pi R_\star^2$ \citep{2003ApJ...598.1387P}. These slopes are  consistent with each other within $3 \sigma$, but samples with a large dynamic range of $\langle |B_I| \rangle$ are desirable to better constrain this result (see text). \label{fig.Lx_flux}}
\end{figure}

We also investigate the trend between the ratio of X-ray-to-bolometric luminosity $L_X/L_{\rm bol}$ and the large-scale magnetic field. Considering the dwarf stars represented by the filled symbols in Figure~\ref{fig.ap2}, we found that {$L_X/L_{\rm bol} \propto \langle |B_V| \rangle^{1.61\pm 0.15}$ (solid line).

\begin{figure}
\includegraphics[width=80mm]{legend-page7.pdf
\caption{Correlation between the ratio of X-ray-to-bolometric luminosity ($L_X/L_{\rm bol}$) and large-scale magnetic field  derived from the ZDI technique ($\langle |B_V| \rangle$) for the non-accreting stars in our sample. The open symbols are as in Figure~\ref{fig.b_prot} and were not considered in our fit (solid line). The dashed line indicates the saturation plateau for $\rm Ro \lesssim 0.1$ at $\log(L_X/L_{\rm bol}) \simeq -3.1$  \citep{2011ApJ...743...48W}. The dotted line, at an arbitrary vertical offset, is indicative of the slope found from ZB measurements \citep[derived from results by][]{2001ASPC..223..292S,2011ApJ...743...48W}.
\label{fig.ap2}}
\end{figure}

\subsection{Accreting PMS stars}\label{sec.ttauri}
Figure \ref{fig.prot_age} shows that the accreting stars form a different population compared to the disc-less stars. Besides the presence of the disc regulating the rotation of accreting PMS stars, they are also still contracting towards the ZAMS and, therefore, their radii and internal structures evolve considerably over a short timescale (compared to their MS lifetime).

While the non-accreting stars show significant correlations in almost all the trends investigated in Table~\ref{tab.powerlaw}, the same is not true for the accreting stars. With the exception of the correlation between $\Phi_V$ and $P_{\rm rot}$ (discussed below), all the other trends investigated resulted in relatively low correlation coefficients and/or relatively high null-probabilities ($> 0.01\%$).

In accreting systems,  the polar strength of the dipole component $B_{\rm dip}$ is particularly relevant for determining the disc truncation radius and the balance of torques in the star-disc system \citep[e.g.,][]{2012ApJ...744...55A}. \citet{2012ApJ...755...97G} and, more recently confirmed by \citet{2014MNRAS.437.3202J},  found that $B_{\rm dip}$ is correlated with $P_{\rm rot}$, such that stars with weak dipole components tend to be rotating faster than stars with strong dipole components. They attributed this correlation as a signature of star-disc interaction. Using the data for $B_{\rm dip}$ listed in \citet{2012ApJ...755...97G}, \citet{2013MNRAS.436..881D} and \citet{2014MNRAS.437.3202J} together with the data presented in Table~\ref{table}, we found that $B_{\rm dip} \propto P_{\rm rot}^{2.05\pm 0.41}$, with a Spearman's rank correlation coefficient of $\rho=0.83$ and a probability of the null hypothesis that no correlation exists of $\ll 0.01\%$. In addition, we also found that $\Phi_V \propto B_{\rm dip}^{1.07 \pm0.22}$ ($\rho=0.90$). These two strong correlations directly explain the strong correlation reported in Table \ref{tab.powerlaw} between $\Phi_V$ and $P_{\rm rot}$, where we found that $\Phi_V \propto P_{\rm rot} ^{2.19\pm0.43}$, when the error in $\Phi_V$ is properly accounted for. We caution, however, that these correlations are based on a small sample of accreting stars and more data are required for confirmation.

Accreting PMS stars with the simplest magnetic fields, and the largest magnetic flux, are therefore the slowest rotators.  The correlations reported here are likely a manifestation of the star-disc interaction, as suggested by  \citet{2012ApJ...755...97G}.  Stars with more organised large-scale magnetospheres with stronger dipole components are able to truncate their discs at larger radii, where the Keplerian spin rate of the inner disc (and that of the star if they exist in a disc-locked state) is slower than it would be at the smaller truncation radii expected for stars with more complex magnetospheres with weaker dipole components.  The latter sample of stars, with their lower magnetic flux $\Phi_V$, would therefore be faster rotators.\footnote{If an accreting PMS is not locked to its disc, then a stronger dipole component allows the disc to be truncated at a larger radius, closer to co-rotation.  This in turn means the star will experience smaller magnetic and accretion related spin-up torques (e.g. \citealt{2013arXiv1309.7851B} and references therein), and will more likely remain a slower rotator compared to a star with a weaker more complex magnetic field, as it evolves towards a disc-locked state.}

Note that, because  most PMS accreting stars observed to date have $\rm Ro \ll 0.1$ and are in the saturated regime, their dynamo-generated magnetic fields are not expected to depend on their rotation rates. The correlation between $\Phi_V$ and $P_{\rm rot}$ we observe is what we would expect if the rotation rates of accreting PMS stars are being dominated by star-disc interaction. In other words, the stellar magnetic field (via star-disc interaction) sets the rotation rate of accreting PMS stars, rather than the rotation rate setting the magnetic flux/strength through the dynamo field generation process.  Or, at the very least, star-disc effects dominate any underlying dynamo relations at this early phase of stellar evolution.

\section{Discussion}\label{sec.discussion}
\subsection{Comparison between results from Zeeman broadening and Zeeman-Doppler imaging}\label{sec.comparison}
In this Section, we compare  trends with magnetism. Stellar magnetic fields were obtained by two different techniques. The Zeeman-induced line broadening of unpolarised light (Stokes I), or Zeeman broadening (ZB) technique, yields estimates of the average of the total unsigned surface field strength (small- and large-scale structures), without providing information of the topology of the field. The Zeeman Doppler imaging (ZDI) technique (Stokes V), on the other hand, is able to reconstruct the intensity and topology of the stellar magnetic field, but cannot reconstruct the small-scale field component, which is missed within the resolution element of the reconstructed ZDI maps \citep{2013AN....334...48M}.%
\footnote{The reconstructed fields are expressed as a spherical-harmonic expansion. Note that, the faster the rotation of the star, the larger is the spatial resolution. As a consequence, the ZDI reconstruction technique is able to recover magnetic fluxes at high order $l$ of the spherical harmonics expansion for faster rotating objects \citep[see][for a detailed analysis of the effects of resolution on what is recovered in the ZDI maps]{2009MNRAS.398..189H}. In our sample, the maximum value of $l$ varies from $l_{\rm max} \sim 2 $ \citep[e.g., for HD~76151,][]{2008MNRAS.388...80P} to $\sim 30$ \citep[e.g., for HD~141943,][]{2011MNRAS.413.1922M}. To verify the existence of a possible bias in the reconstructed ZDI field with spatial resolution, we have recalculated $\langle |B_V| \rangle$ for all the objects taking into account only the lowest orders of $l$. We adopted  $l_{\rm cutoff} = \min(5, l_{\rm max})$ and recomputed the power-law indices $p$ for all the relations presented in Table~\ref{tab.powerlaw}. The recalculated $p$ are consistent within the fitting errors to what is presented in Table~\ref{tab.powerlaw}. The similarity between the relations when considering $\langle |B_V| \rangle(l_{\rm cutoff})$ and $\langle |B_V| \rangle(l_{\rm max})$ is due to the fact that the largest powers in the harmonic expansions are in the low-$l$ modes. This indicates that the different spatial resolution of the data considered here does not generate bias in the derived $\langle |B_V| \rangle$ and, consequently, that our derived relations in Table~\ref{tab.powerlaw} are robust. \label{foot}}

These techniques are, nevertheless, complementary. The ZB technique is limited to slowly rotating objects ($v \sin(i)\lesssim 20$~km~s$^{-1}$), as broadening of spectral lines caused by rotation makes it more difficult to disentangle broadening caused by the Zeeman effect. The ZDI measurements, on the other hand, favour rapidly rotating objects (a few tens of km~s$^{-1}$, although  recently ZDI measurements of more slowly rotating objects have become available). As a result,  it is not always possible to obtain field measurements using both techniques for the same object \citep[see][for a more in depth discussion]{2012EAS....57..165M}. Because of that, in this Section, instead of comparing results of both techniques on a case-by-case basis, we compare the results achieved from these techniques on samples of stars (which in general do not have overlapping members). The comparison presented next is summarised in Table~\ref{tab.comp}. The dotted lines in Figures~\ref{fig.b_prot} to \ref{fig.ap2} indicate the slopes found from ZB measurements, assuming arbitrary vertical offsets.

\begin{table*}
\centering
\caption{Comparison between trends found using Zeeman Doppler Imaging (ZDI, this work) and Zeeman broadening (ZB) measurements for stars in the unsaturated regime. References for the latter are provided in the last column. \label{tab.comp}}
\begin{tabular}{lllccc}
\hline
From ZDI (this work) & From ZB  & Reference\\
\hline
$\langle |B_V| \rangle \propto P_{\rm rot}^{-1.32 \pm 0.14}$ & $\langle |B_I| \rangle \propto P_{\rm rot}^{-1.7}$ &\citet{1996IAUS..176..237S} \\
$\langle |B_V| \rangle \propto \rm Ro^{-1.38 \pm 0.14}$ & $\langle |B_I| \rangle \propto \rm Ro^{-1.2}$ &\citet{2001ASPC..223..292S} \\
$L_X^{\rm (all)} \propto \Phi_V^{0.913 \pm 0.054}$ & $L_X^{\rm (all)} \propto \Phi_I^{1.13}$ &\citet{2003ApJ...598.1387P} \\
$L_X^{\rm (dwarfs)} \propto \Phi_V^{1.80\pm 0.20}$ & $L_X^{\rm (dwarfs)} \propto \Phi_I^{0.98\pm 0.19}$ &\citet{2003ApJ...598.1387P} \\
$L_X/L_{\rm bol} \propto \langle |B_V| \rangle^{1.61 \pm 0.15}$ & $L_X/L_{\rm bol} \propto \langle |B_I| \rangle^{2.25}$ &\citet{2001ASPC..223..292S,2011ApJ...743...48W} \\
\hline
\end{tabular}
\end{table*}

Observations of  magnetic fields of about a dozen stars using ZB have revealed that $\langle |B_I| \rangle \propto P_{\rm rot}^{-1.7}$ \citep{1996IAUS..176..237S} and, in terms of Rossby numbers, $\langle |B_I| \rangle \propto \rm Ro^{-1.2}$ \citep{2001ASPC..223..292S}. {In both works, a mix of saturated and unsaturated stars are considered, which implies that if one were to only consider the stars in the unsaturated regime, the slopes would be steeper than the ones  derived by \citet{1996IAUS..176..237S,2001ASPC..223..292S}.} Using the ZDI measurements of the large-scale field $\langle |B_V| \rangle$, we found for the non-accreting stars that {$\langle |B_V| \rangle \propto P_{\rm rot}^{-1.32 \pm 0.14}$ and $\langle |B_V| \rangle \propto \rm Ro^{-1.38 \pm 0.14}$} (the latter considering only points with $\rm Ro \gtrsim 0.1$, corresponding to the unsaturated stars). The similarities in the dependences of $\langle |B_I| \rangle$ and $\langle |B_V| \rangle$ with $P_{\rm rot}$ and $\rm Ro$ might indicate that fields measured by ZDI (large scale) and ZB (large and small scale) are coupled to each other \citep[see also][]{2014MNRAS.439.2122L}. This apparent coupling, therefore, might indicate that small- and large-scale fields share the same dynamo field generation processes, at least for stars in the unsaturated regime.

Another relevant comparison is the one between X-ray emission and magnetism as derived by ZB and ZDI (Figure~\ref{fig.Lx_flux}). \citet{2003ApJ...598.1387P} found that $L_X^{\rm (all)} \propto \Phi_I^{1.13\pm 0.05}$, where $\Phi_I = \langle |B_I| \rangle 4 \pi R_\star^2$ is the unsigned magnetic flux derived from ZB. In this relation, \citet{2003ApJ...598.1387P} considered magnetic field observations of the Sun (quiet Sun, X-ray bright points, active regions, and integrated solar disk), dwarf stars and PMS accreting stars, spanning about $12$ orders of magnitude in magnetic flux. When we include all the objects in our sample, we found that {$L_X^{\rm (all)} \propto \Phi_V^{0.913 \pm 0.054}$}, consistent to the nearly linear trend found by \citet{2003ApJ...598.1387P}.  When considering only the sample of $16$ G, K and M dwarf stars (i.e., no solar data nor accreting PMS stars), \citet{2003ApJ...598.1387P} found that $L_X^{\rm (dwarfs)} \propto \Phi_I^{0.98\pm 0.19}$, which is flatter than the correlation we found ($L_X^{\rm (dwarfs)} \propto \Phi_V^{1.80\pm 0.20}$), based on a larger sample of {$61$} dwarf stars\footnote{Note that if we include the open symbols (M dwarf stars without age estimates) in the fit presented in Figure~\ref{fig.Lx_flux}, the slope we derive is slightly flatter ($L_X^{\rm (dwarfs)} \propto \Phi_V^{1.49\pm 0.17}$), yet still consistent with the value quoted in the text.}. Because of the relatively large errors in the power-law exponent of these relations, within $3 \sigma$ they are still consistent with each other. This is a point worthy of further investigation. Finding a different power law for $\Phi_V$ and $\Phi_I$ may shed light on how the small-scale and large-scale field structures contribute to $L_X$. By reducing the errors in the power-law fits (e.g., increasing the dynamic ranges of the fits, in particular in the ZB one), it would be possible to assess whether these relations are indeed consistent with each other.

Finally, in Figure~\ref{fig.ap2} we showed that {$L_X/L_{\rm bol} \propto \langle |B_V| \rangle^{1.61\pm 0.15}$} for the unsaturated stars. To the best of our knowledge, there is no such correlation constructed for $\langle |B_I| \rangle$. We therefore combined the results of \citet[][$\langle |B_I| \rangle \propto \rm Ro^{-1.2}$]{2001ASPC..223..292S}  and \citet[][$L_X/L_{\rm bol}\propto \rm Ro^{-2.7 \pm 0.13}$]{2011ApJ...743...48W} to derive that $L_X/L_{\rm bol} \propto \langle |B_I| \rangle^{2.25}$. Again, we note that the slope derived in \citet{2001ASPC..223..292S} could be steeper if only the unsaturated stars were considered. Therefore, the slope of $2.25$ we derive is an upper limit. Although we found  a less steep dependence of $L_X/L_{\rm bol}$ with $\langle |B_V| \rangle$ than with $\langle |B_I| \rangle$, given the uncertainties involved in the determination of these slopes, they can be considered consistent with each other. Unfortunately and in particular because of the small number of unsaturated stars with available $\langle |B_I| \rangle$ measurements, it is still not possible to ascertain how large- and small-scale fields contribute to X-ray emission.

\subsection{Saturation}\label{sec.saturation}
Stars in the saturated regime show similar levels of X-ray-to-bolometric luminosity. In X-rays, saturation occurs for stars with $\rm Ro \lesssim 0.1$ \citep[e.g.,][]{2000MNRAS.318.1217J,2003A_A...397..147P,2011ApJ...743...48W}. In terms of their magnetism, there is evidence that the total field $\langle |B_I| \rangle$ also saturates for $\rm Ro \lesssim 0.1$ \citep{2009ApJ...692..538R} and it would be interesting to investigate whether saturation is also present in the large-scale magnetic field $\langle |B_V| \rangle$. In Figure~\ref{fig.b_rossby}a, we also present the remaining M dwarf stars, without age estimates (open symbols), collected from the samples in \citet{2008MNRAS.390..545D} and \citet{2008MNRAS.390..567M,2010MNRAS.407.2269M}. They are in the X-ray saturated regime, with small $\rm Ro$ (\rm Ro\ taken from \citealt{2008MNRAS.390..545D,2008MNRAS.390..567M,2010MNRAS.407.2269M}). {It seems that these objects show different levels of saturation of $\langle |B_V| \rangle$, with the mid-M dwarfs (green circles) saturating at $\log({\langle |B_V| \rangle}/[{\rm G}]) \sim 2.6$ while the early Ms (blue squares) at $\log({\langle |B_V| \rangle}/[{\rm G}]) \sim 1.7$ (horizontal dashed lines in Figure~\ref{fig.b_rossby}a).  \citet{2008MNRAS.390..545D} suggested that the step in the saturation level between early-Ms and mid-Ms is caused by different efficiencies at producing large-scale versus small-scale fields, where rapidly-rotating mid-M dwarfs generate fields on larger spatial scales than early-M dwarfs \citep[see also][where a direct comparison between $\langle |B_V| \rangle$ and $\langle |B_I| \rangle$ was performed for a small sample of M dwarf stars]{2009A&A...496..787R}. The saturation of late-M dwarfs (red circles), on the other hand, was shown to be divided into two distinct categories, either more similar to the saturation level of early-Ms or that of mid-Ms \citep{2010MNRAS.407.2269M}. Although in \citet{2008MNRAS.390..545D}, \citet{2009A&A...496..787R} and \citet{2010MNRAS.407.2269M} the three components of the reconstructed ZDI field were considered (radial, azimuthal and meridional) and in the present work we only focus on the radial component, the trends obtained in Figure~\ref{fig.b_rossby}a are essentially the same as those discussed by these authors.

A unified saturation plateau for $\rm Ro \lesssim 0.1$ is observed if the magnetic flux $\Phi_V$ is considered instead of the magnetic field intensity $\langle |B_V| \rangle$ (Figure~\ref{fig.b_rossby}b). This occurs at $\log{(\Phi_V/[{\rm Mx}])}\sim 24.25$. There is a spread in this plateau, in particular caused by the late-M dwarfs (red circles). This spread has also been observed in X-rays, for objects later than M$6.5$ \citep{2014ApJ...785...10C}. The saturation of $\Phi_V$ has not been recognised before. Observations of more objects at low $\rm Ro$ are desirable to provide better constraints  on this saturation. }

{In Figure~\ref{fig.ap2}, we investigated how $L_X/L_{\rm bol}$ varied with magnetism. Over-plotted to Figure~\ref{fig.ap2} are the remaining M dwarf stars, without age estimates (open symbols), from the samples in \citet{2008MNRAS.390..545D} and \citet{2008MNRAS.390..567M,2010MNRAS.407.2269M}. The saturation value  of $\log(L_X/L_{\rm bol}) = -3.13\pm 0.08$, derived from the rotation-activity study performed by \citet{2011ApJ...743...48W}, is shown as a dashed line. We see that the mid- and late-M dwarf stars approximately lie along this plateau. We did a similar analysis between  $L_X/L_{\rm bol}$  and magnetic flux $\Phi_V$ and found that in this case, the plateau disappears as early- and mid-M dwarfs lie approximately along the same trend of  $L_X/L_{\rm bol}$ and $\Phi_V$  as the remaining objects ($L_X/L_{\rm bol} \propto \Phi_V^{1.82 \pm 0.18}$).}

Figure~\ref{fig.sketch} shows a possible interpretation of our results, where we show a three-dimensional sketch of $L_X/L_{\rm bol}$, $\langle |B_V| \rangle$ and \rm Ro. In this sketch, Figures~\ref{fig.b_rossby} ($\langle |B_V| \rangle$ versus \rm Ro) and \ref{fig.ap2} ($L_X/L_{\rm bol}$ versus $\langle |B_V| \rangle$) are projections of a multi-dimensional distribution, as is the well-known relation between $L_X/L_{\rm bol}$ and \rm Ro. These projections are illustrated by dashed lines. According to our interpretation, the saturation plateau is actually a `plane' (grey retangular box), where objects of  different internal structures (i.e., different masses) are located at different regions (drawn as blue stripes in our sketch). Each one of these stripes gives rise to the mass-dependent plateaus in the projected plane of $\{\langle |B_V| \rangle,\rm Ro\}$ (cf.~Figure~\ref{fig.b_rossby}) and it also accounts for the shift in $\langle |B_V| \rangle$ observed for the mid-M dwarfs  in the projected plane of $\{L_X/L_{\rm bol},\langle |B_V| \rangle\}$ (cf.~Figure~\ref{fig.ap2}). The unsaturated stars  consist of a tighter distribution of points (solid red stripe). In Figure~\ref{fig.sketch}, we place our points in the three-dimensional space of $\{\langle |B_V| \rangle,\rm Ro,L_X/L_{\rm bol}\}$, but it is worth noting that the activity relation is a function of other quantities as well, such as, age and mass.

\begin{figure}
\includegraphics[width=80mm]{export_nobackground2-eps-converted-to.pdf}
\caption{The activity relation is a complex function of many variables, such as age, mass, rotation and magnetism. Here we present a sketch in the three-dimensional space of $\{\langle |B_V| \rangle,\rm Ro,L_X/L_{\rm bol}\}$, presenting a possible interpretation of how these quantities are related to each other (blue and red stripes). Figures~\ref{fig.b_rossby} ($\langle |B_V| \rangle$ versus \rm Ro) and \ref{fig.ap2} ($L_X/L_{\rm bol}$ versus $\langle |B_V| \rangle$) are projections of this multi-dimensional distribution, as is the well-known relation between $L_X/L_{\rm bol}$ and \rm Ro. These three projections are illustrated by dashed lines. The saturation plateaus seen in the projections form a saturation `plane' (grey retangular box) in the three-dimensional view, where objects of different masses are located at different regions (blue stripes).
\label{fig.sketch}}
\end{figure}

\subsection{Stars with hot Jupiters}\label{sec.hjhosts}
Stars with close-in massive planets (or ``hot Jupiters'', hJs) can experience strong tidal forces that may affect their rotation rates. It is believed that some stars that harbour hJs might have spun-up as a consequence of inward planetary migration \citep{1996Natur.380..606L, 2003ApJ...588..509G, 2009MNRAS.396.1789P, 2011MNRAS.415..605B}. Among the stars in our sample, $7$ of them host hJs ($12$ ZDI maps shown as orange symbols in our figures). From Figure~\ref{fig.b_prot}, we note that these stars do not seem to have magnetic and rotation properties that differ from the remaining population of disc-less stars. \citet{2013MNRAS.435.1451F} also compared the large-scale magnetic topology of hJ-host stars adopted in our sample with that of stars without detected hJs and showed that both groups have similar magnetic field topologies.

Our findings suggest that the planets orbiting the h-J hosts in our sample might not be affecting significantly the rotation nor the large-scale magnetism of their host stars. A possible reason for this might be that tides in the systems analysed here are too weak to spin-up the host star \citep{2010A&A...512A..77L} and, consequently, to change its magnetic properties. Alternatively, if these planets were at some point in the past able to affect the rotation of the star, the reaction of the dynamo should have occurred in a relatively short timescale.

It is also worth pointing out that the h-J hosts seem to be systematically shifted towards lower $\langle |B_V| \rangle$ values at a given age compared to solar-like stars (Figure~\ref{fig.B_age}). This is likely to be a bias from planet search surveys, which prioritise targets with lower activity and, therefore, lower magnetism.

\subsection{Accreting PMS stars}\label{sec.accreting}
For accreting PMS stars, \citet{2007ApJ...664..975J} found no correlation between any magnetic and stellar/dynamo parameters\footnote{\citet{2011ApJ...729...83Y} also found no correlations between the magnetic and dynamo parameters when considering PMS stars in the Orion Nebula Cluster (ONC), the TW Hydrae association, and the same stars from Taurus considered by \citet{2007ApJ...664..975J}. A comparison of their sample of ONC stars with the catalog of \citet{1998AJ....116.1816H} reveals it to be a mixture of both accreting and non-accreting PMS stars.  However, \citet{2011ApJ...729...83Y} do find a reduction in $\Phi_I$ with age which they attribute to the decrease in stellar radius as PMS contract towards the ZAMS.  We do not find any statistically significant correlation between $\Phi_V$ and age for our population of PMS stars (see Table \ref{tab.powerlaw}).  This may be because our sample size is too small (16 magnetic maps of 11 different accreting PMS stars) compared to the 31 stars considered by \citet{2011ApJ...729...83Y}. Likewise, \citet{2007ApJ...664..975J} found no correlation between $\Phi_I$ and $t$ in his smaller sample of 14 accreting PMS stars.}, and in particular, found no correlation between the magnetic flux $\Phi_I$, estimated from the average surface magnetic field as calculated from ZB measurements, and $P_{\rm rot}$.  Out of the parameters that we have considered in Table \ref{tab.powerlaw}, the only statistically significant correlation we have found for accreting PMS stars is between the magnetic flux $\Phi_V$, derived from the magnetic maps obtained through ZDI, and $P_{\rm rot}$.  As discussed in Section \ref{sec.ttauri}, this is likely being driven by the star-disc interaction, which is controlled by the large-scale field topology probed with ZDI.  ZB studies do not give access to the large-scale field topology, but are sensitive to the entirety of the stellar surface magnetic field, including the small-scale closed field regions that play no part in the star-disc interaction.  The large-scale stellar magnetic field, in particular the dipole component $B_{\rm dip}$ of the multipolar magnetosphere, is the most important in terms of controlling the interaction with the disc (e.g. \citealt{2012ApJ...744...55A,2012ApJ...755...97G,2014MNRAS.437.3202J}); $B_{\rm dip}$ can only be determined from ZDI studies.  Therefore, the lack of correlation between $\Phi_I$ and $P_{\rm rot}$ does not pose a problem for our argument that the clear correlation between $\Phi_V$ and $P_{\rm rot}$ reported in this paper is driven by magnetic star-disc interaction.

\section{Magnetochronology: magnetism as a new way to assess stellar age}\label{sec.magnetochronology}
One of our most interesting findings is the empirical trend between large-scale magnetism and age. Age is one of the most fundamental stellar parameters. However, the task of measuring ages is a very difficult one, with several methods having been used \citep[see][for recent reviews]{2010ARA&A..48..581S,2013arXiv1311.7024S}. For example, by solving the equations of the internal structure of the star, stellar evolution codes can be used as a tool to determine stellar age, from observational quantities, such as effective temperatures and luminosities. {As in the MS phase, these parameters do not change significantly, isochrone dating is more unreliable for more evolved MS stars.}
The relation found between $P_{\rm rot}$ and age first recognised by \citetalias{1972ApJ...171..565S} has served as the basis of the gyrochronology method, which is able to provide stellar age estimates from rotation measurements \citep{2003ApJ...586..464B,2010ApJ...721..675B}. For young objects, the presence of lithium can constrain ages \citep{2010IAUS..268..359S}. Asteroseismology can also provide a means to derive stellar age \citep{1988IAUS..123..295C,2005MNRAS.356..671O}, although this method has been more widely applied to bright stars. Chromospheric activity can also be used as an astrophysical clock, although it seems to be more robust for objects with ages $\lesssim 2$~Gyr \citep{2013A&A...551L...8P}. The empirical relation that we identified between the large-scale magnetic fluxes and age (Figure~\ref{fig.B_age}) can be used as an alternative method to estimate the age of stars. However, the relatively large spread of this correlation implies that this method, similarly to other age-dating methods, would carry significant imprecisions in age determination. Moreover, when compared to photometric measurements of rotation periods, the ``magnetochronology'' method is more expensive in terms of observing time and field reconstruction than the gyrochronology method.

Our empirical trends are also relevant for investigations of rotational evolution of low-mass stars, as they provide important constraints on the evolution of the large-scale magnetism of cool stars, as well as their dependence on stellar rotation. For example, the relations $\langle |B_V| \rangle$ versus $t$ and $\langle |B_V| \rangle $ versus $ \rm Ro$ can be implemented in models investigating the evolution of mass and angular momentum loss \citep[e.g.,][]{2013A&A...556A..36G}. These relations also provide important constraints for stellar dynamo studies.

\section{Summary and conclusions}\label{sec.conclusions}
In this paper, we investigated how the large-scale surface magnetic fields of cool dwarf stars, reconstructed using the ZDI technique, vary with age, rotation period, Rossby number and X-ray luminosity. Our sample consists of {$73$} stars in the mass range between {$0.1$ and $2.0~M_\odot$} and spans about 4 orders of magnitude in age (from a Myr to almost $10$~Gyr). As some of the stars have magnetic maps that were obtained at multiple observation epochs, our sample consists of {$104$}~data points, including some PMS objects with on-going accretion. In order to separate the effects that accretion/PMS contraction might play on the rotational evolution of the stars, we have separated our sample into two populations.

For the population of accreting stars, we find few statistically significant correlations, except for the correlation between the unsigned magnetic flux $\Phi_V$ and $P_{\rm rot}$ (and between $\langle |B_V| \rangle$ and the polar strength of the dipole component $B_{\rm dip}$ and $\Phi_V $ versus $ B_{\rm dip}$). We attributed these correlations to a signature of star-disc interaction rather than being caused by the underlying dynamo field generation process.

For the population of non-accreting stars, we showed that their unsigned large-scale magnetic field strength $\langle |B_V| \rangle$ is related to age $t$ as {$\langle |B_V| \rangle \propto t^{-0.655 \pm 0.045}$}, with a high statistical significance (Spearman's rank correlation coefficient of {$-0.79$} and a very small null hypothesis probability). This relation presents a similar power dependence empirically identified in the seminal work of \citetalias{1972ApJ...171..565S}, which has served as the basis of the gyrochronology method to determine stellar ages from stellar rotation measurements. Our empirically-derived magnetism-age relation could be used as a way to estimate stellar ages, although it would not provide better precision than the currently adopted methods.

Theoretically, \citetalias{1972ApJ...171..565S}'s relation can be explained on the basis of the simplified wind model of \citet{1967ApJ...148..217W}, further assuming that a linear dynamo of the type $B \propto \Omega_\star \propto P_{\rm rot}^{-1}$ is in operation. Empirically, we found that the large-scale unsigned surface field $\langle |B_V| \rangle$ scales with the rotation period of the star as {$\langle |B_V| \rangle \propto P_{\rm rot}^{-1.32 \pm 0.14}$ or, in terms of Rossby number, $\langle |B_V| \rangle \propto \rm Ro^{-1.38\pm 0.14}$}. Our data, therefore, gives support for a linear-type dynamo.  Our empirically-derived relations are relevant for investigations of rotational evolution of low-mass stars and give important observational constrains for stellar dynamo studies.

We also compared the trends we found in the ZDI data to trends empirically found using Zeeman broadening measurements of magnetic field strengths $\langle |B_I| \rangle$. For the unsaturated stars, the similar dependences of $\langle |B_I| \rangle$ and $\langle |B_V| \rangle$ with $P_{\rm rot}$ and $\rm Ro$ indicates that fields measured by ZDI (large scale) and ZB (large and small scale) are coupled to each other. This might indicate that small- and large-scale fields share the same dynamo field generation processes. For the stars in the saturated regime, saturation of $\langle |B_I| \rangle$ occurs for $\rm Ro \lesssim 0.1$ at {$\langle |B_I| \rangle \sim 3$}~kG \citep[][essentially for M dwarfs]{2009ApJ...692..538R}, while for $\langle |B_V| \rangle$, saturation seems to have a bimodal distribution \citep{2008MNRAS.390..545D} at ${\langle |B_V| \rangle} \sim 10^{1.7}$~G  for the early-Ms and at ${\langle |B_V| \rangle} \sim 10^{2.6}$~G for the mid-Ms. We also found saturation of $\Phi_V$ at  ${\Phi_V} \sim 10^{24.25}$~Mx  for $\rm Ro \lesssim 0.1$, but this is no longer bimodal as in the case of $\langle |B_V| \rangle$. Observations of more objects at low $\rm Ro$ are desirable to provide better constraints  on the saturation of $\Phi_V$.

We also investigate how the small- and large-scale structures contribute to X-ray emission (Figures~\ref{fig.Lx_flux} and \ref{fig.ap2}). For the unsaturated stars, these contributions between X-ray emission and $\langle |B_V| \rangle$ or $\langle |B_I| \rangle$ have similar slopes within $3\sigma$, but samples with large dynamic range of $\langle |B_I| \rangle$ are required to better constrain this result.

The plots we presented in this paper could be understood as projections of a complex, multi-dimensional distribution, dependent on quantities such as $L_X/L_{\rm bol}$, $\langle |B_V| \rangle$, rotation, age and internal structure. In Figure~\ref{fig.sketch}, we offered a possible interpretation of this distribution  in the three-dimensional space of $\{\langle |B_V| \rangle,\rm Ro,L_X/L_{\rm bol}\}$. In this view, the unsaturated stars comprise a tight distribution of points, while the saturated objects give rise to a saturation `plane' (instead of a plateau), where objects of different masses are located at different regions (shown as blue stripes in Figure~\ref{fig.sketch}).

New nIR spectropolarimeters, such as SPIRou \citep[e.g.,][]{2013sf2a.conf..497D}, currently under-construction for the Canada-France-Hawaii telescope, will be ideally suited for further comparison between the ZB and ZDI techniques. It will allow magnetically sensitive, Zeeman broadened, lines to be measured within the same spectra as used to reconstruct magnetic maps, thereby allowing a more direct comparison between $\langle |B_V| \rangle$ and $\langle |B_I| \rangle$.

\section*{Acknowledgements}
AAV acknowledges support from a Royal Astronomical Society Fellowship and from the Swiss National Science Foundation via an {\it Ambizione} Fellowship. SGG acknowledges support from the Science \& Technology Facilities Council (STFC) via an Ernest Rutherford Fellowship [ST/J003255/1]. JB, PP, and CPF acknowledge support from the ANR 2011 Blanc SIMI5-6 020 01 ``Toupies: Towards understanding the spin evolution of stars'' (\url{http://ipag.osug.fr/Anr_Toupies/}). AAV would like to thank Prof.~Keith Horne and Dr Kate Rowlands for advice in the statistical analysis. NSO/Kitt Peak data used here are produced cooperatively by NSF/NOAO, NASA/GSFC, and NOAA/SEL.

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redpajama_set_name: RedPajamaArXiv


May 29, 2012 Alarm Magazine reviews Rubble Guts & BB Eye.
May 29, 2012 Pop Break reviews Rubble Guts & BB Eye.
May 29, 2012 Under The Radar reviews Rubble Guts & BB Eye.
May 26, 2012 The New York Times reviews Rubble Guts & BB Eye.
May 25, 2012 The Dallas News reviews Rubble Guts & BB Eye.
May 25, 2012 The Star-Telegram reviews Rubble Guts & BB Eye.
April 25, 2012 East Bay Express reviews Rubble Guts & BB Eye.


On behalf of Powell Law Offices, P.C. posted in blog on Monday, December 11, 2017.
A number of people struggling financially take steps toward improving their lives at the start of the new year. This can involve divorce, bankruptcy, or both. While no one looks forward to bankruptcy or divorce, the result of these difficult processes can be extremely beneficial in the long-term.
Most people choose to wait until after the holidays to file for bankruptcy and divorce. In January, there is typically an influx of divorce cases. January has become known as "divorce month" for this reason.
Financial struggles are a reason for the divo rce. Financial arguments are a leading cause of divorce. Financial goals and spending habits are important. Major differences can lead to irreconcilable arguments, as well as overwhelming debt. Filing for bankruptcy after divorce can be a way out.
You rel y on two incomes. If you stopped pursuing a career to focus on raising a family or simply need two incomes to pay bills, bankruptcy can help you start to life on your own without overwhelming debt.
Th ere is debt you were unaware of . If a spouse ran up credit card debt, failed to pay taxes, or otherwise misrepresented their true financial situation, bankruptcy after divorce can be a vehicle to avoid lasting debt. Even if you were not aware of the purchases or debts, you may still be subjected to creditors depending on the type of debt it is. Bankruptcy can help.
It is fairly common to obtain bankruptcy protection after divorce. Of course, the right path will depend on your individual circumstances. For those looking to get out from a bad financial situation, however, getting both a divorce and bankruptcy protection can be the start to a new personal and financial life free from debt and overwhelming stress.
This blog is not legal advice. If you are considering either divorce or bankruptcy, speak with an experienced attorney who understands both divorce and bankruptcy prior to undertaking either.


text:
Archive for earthquake
Native American Superheroes, Foreign Earthquakes, Monster Puppets
Posted in Evil, Foreign Horror, Giant Monsters, Nature Gone Wild, Science Fiction with tags A Breath Away, aftershocks, Batman, beast, earthquake, Evil, Foreign Horror, Giant Monsters, Jeffrey Veregge, Kaiju Confidential, Native American, natural disaster, Nature Gone Wild, Netflix, Paris, Parisians, Port Gamble S'Klallam Tribe, puppts, radioactive spiders, Science Fiction, sex, Spider-Man, superheroes, Superman, Supernatural, Velvet Buzzsaw on January 22, 2019 by Drinkin' & Drive-in
Came across the fantastic, minimalist sci-fi/fantasy art of artist, Jeffrey Veregge, and his pretty dang funny intro to his bio: "My origins are not supernatural, nor have they been enhanced by radioactive spiders. I am simply a Native American artist and writer whose creative mantra in best summed up with a word from my tribe's own language as: "tačaxétəŋ", which means, "get into trouble." (Note to Mr. Veregge — I probably screwed up your tribe's language on that one — please don't kill me in half.)
Jeffrey Veregge is a member of the Port Gamble S'Klallam Tribe and his Native American artistic stylings cast guys like Batman, Superman and Spider-man into refreshing new interpretations. And hey, put a .com after his name and go see all the other incredible art he does.
Before we all go back to the art store to return unused art supplies because we're not even in the ballpark of Jeffrey's artistic talent (there's always a bathroom that needs cleaning), here are a few upcoming horror/sci-fi movies that may or may not insult Native Americans…
A BREATH AWAY (February 1, 2019)
"Parents are desperately trying to save their daughter from a deadly toxic mist that has engulfed Paris after an earthquake. Only those lucky enough to escape to the rooftops of the city were able to survive; their daughter, who suffers from a genetic condition requiring her to live in a hermetic box that filters the air, is trapped below."
If ever there was a situation that could be referred to as "f'd in the b-hole," this is it. As for the toxic mist engulfing Paris after an earthquake, I bet it was all the Parisians simultaneously fright-farting their britches off during said natural disaster. What follows next is aftershocks and butt-croissants.
VELVET BUZZSAW (February 1, 2019/Netflix™)
"After a series of paintings by an unknown artist are discovered, a supernatural force enacts revenge on those who have allowed their greed to get in the way of art."
Velvet Buzzsaw is also a sex term used by dirty-minded people. I don't know why I know that.
KAIJU CONFIDENTIAL (2019)
"Grigon's not the toughest beast on the block, but he's certainly the most neurotic. When he discovers the legendary Mega-Hydra rampaging on his turf, it becomes a stand-off of passive-aggressive proportions."
This looks like a puppet show. And we all know what is shoved up the ass-end of a puppet.
Toying With Godzilla, A Nice Exorcist, Spider-Man On Vacation
Posted in Evil, Foreign Horror, Giant Monsters, Godzilla, Nature Gone Wild, Science Fiction with tags ancient spirit, Animas, Christchurch, cow, earthquake, European, Evil, exorcist, Fire Godzilla, Foreign Horror, Giant Monsters, Godzilla, Godzilla: King of the Monsters, Hell, Holy, Jakks Pacific, King Ghidorah, Monsters, Mothra, Nature Gone Wild, Neca, Netflix, New Zealand, Nick Fury, nightmare, priest, Rodan, Science Fiction, Spider-Man, Spider-Man: Far From Home, Spider-Man: Homecoming, superhero, Supernatural, Texas, The Change Over, The Good Exorcist, Toy Ark on January 17, 2019 by Drinkin' & Drive-in
Wanna get toys based on Godzilla: King of the Monsters about the same time the movie comes out on May 31, 2019? Thanks to NECA and Jakks Pacific (and available at Toy Ark), you can and should.
Toys or "Fun Talismans," include Godzilla (duh) and his frenemies, King Ghidorah, Rodan and Mothra. On their press release, though, they said Fire Godzilla will also be included. Did they just send out a spoiler?
Most of the monsters will be 12 inches tall, with one Godzilla version twice that size, whatever that measures out to be. There will also be smaller versions and even a Godzilla mask in case you wanna goon out the neighbors.
While we make room in the toy box, here are a few upcoming horror/sci-fi movies that may or may not goon out the neighbors…
ANIMAS (January 25, 2019/Netflix™)
"Alex is a confident girl with a strong personality and great tenacity. She's very close to her best friend Abraham, to whom she provides constant help and support, as Abraham is a shy, withdrawn and insecure boy, mainly due to the complex relationship between he and his parents. But everything changes when Daniel — Abraham's father — dies in a strange accident, the cause of which is unclear. From this moment on, Alex finds herself on a hallucinatory journey that takes her on a descent into hell, where the line between reality and nightmare becomes blurred to the point that Alex begins to question the foundations of her very existence."
Descent into hell? Hallucinatory journey? The line between reality and nightmare becomes blurred? Sounds like Alex has been hanging out in the same bars as me.
THE GOOD EXORCIST (February 21, 2019/El Rey/VOD)
"A socially awkward but reliable exorcist attempts to remove a difficult demon from a ranch owned by an eccentric family in Texas. However, the demon proves to be more difficult than the priest assumed it would be."
Since this is on a ranch, I totally bet the demon is cow. Hey, it's got horns and shoots some sort of evil fluid from each of its four unholy dangle-y squirt gun type things under its swim suit area. Evil is pronounced "moo" in its hellish language.
SPIDER-MAN: FAR FROM HOME (July 5, 2019)
"Our friendly neighborhood superhero decides to join his best friends Ned, MJ, and the rest of the gang on a European vacation. However, Peter's plan to leave super heroics behind for a few weeks are quickly scrapped when he begrudgingly agrees to help Nick Fury uncover the mystery of several elemental creature attacks, creating havoc across the continent."
Just like the last movie (Spider-Man: Homecoming/2017, in case you forgot), the trailer for the new one is so ridiculously cool, you almost don't need to see the movie. But you'll just have to. And Spider-Man teaming up with Mysterio? I just webbed my pants.
THE CHANGE OVER (2019)
"Sixteen year-old Laura Chant lives with her mother and four-year-old brother Jacko in a low-rent suburb on the edge of earthquake-scarred Christchurch, New Zealand. Laura is drawn into a supernatural battle with an ancient spirit who attacks Jacko and slowly drains the life out of him as the spirit becomes ever younger. Laura discovers her true identity and the supernatural ability within her, and must harness it to save her brother's life."
There's a place called, Christchurch? Sounds like a good place for a Holy war to me. That the place is actually real and is plagued by earthquakes makes me wanna move there and get a front row pew.
Ghost Hotels, Unnatural Disasters and Cigar Zombies
Posted in Classic Horror, Evil, Foreign Horror, Ghosts, Nature Gone Wild, Science Fiction, Slashers, Zombies with tags beer, Channel Zero: Butcher's Block, Channel Zero: No-End House, Christmas, cigar, Classic Horror, Colorado, Creepypasta, Crystal Ballroom, Cuba, Cuban Missile Crisis, Dangerous People, earthquake, Evil, Foreign Horror, Fruity Pebbles, ghost hunters, Ghosts, haunted, Jack Torrance, Kerry Hammond, Nature Gone Wild, Norway, Old Town Pizza, Oregon, Oslo, Oslo Graben, paranormal activity, Poltergeists, Portland, Richter Scale, Rise of the Living Dead, Room 217, Science Fiction, Slashers, spirits, spooky, Stephen King, Sy-Fy Channel, The Benson Hotel, The Overlook Hotel, The Shining, The Stanley Hotel, The Wave, undead, walking dead, White Eagle Saloon, Zombies on December 22, 2017 by Drinkin' & Drive-in
Prepping for my annual solo holiday trek to downtown Portland, OR, my favorite city within 175 miles from where I'm littering. This year will be a bit different as I plan on visiting several Chamber of Commerce endorsed haunted buildings, one of which happens to be the very hotel I'm staying at. (Love the new bathroom upgrades at The Benson, but the ghosts could be a bit more spookier.)
The hotel that's on my bucket list is, of course, The Stanley Hotel (aka, The Overlook Hotel in The Shining), located at 333 E Wonderview Ave, Estes Park, CO. (And in case you need the zip code: 80517.) Their website has this to say about that: "The Stanley Hotel features a variety of rooms with high paranormal activity including the famous Stephen King Suite 217, the Ghost Hunters' favorite room 401; as well as 407, 428 and 1302. These are among our most-requested rooms, availability is limited."
While I polter-hunt/drink in Old Town Pizza, Crystal Ballroom and the White Eagle Saloon, all of which have documented ghost sightings (and tasty snacks), here are a few just released and upcoming horror/sci-fi movies that may or may not scare the Christmas wrap outta you…
DANGEROUS PEOPLE (available now)
"In the early 1970s two murderers pick up a girl in a bar and take her back to their apartment. A moment of brutal violence occurs, which leads to a series of mind games to see who lives and who dies. Dangerous People is a psychedelic trip that is equal parts crazy, scary, sexy, funny, sick and tragic."
Crazy, scary, sexy, funny, sick and tragic. Aren't those the ingredients on Fruity Pebbles™ cereal boxes? (That stuff has more artificial coloring than a beauty parlor.)
CHANNEL ZERO: BUTCHER'S BLOCK (2018)
"Inspired by Kerry Hammond's 'Search and Rescue Woods' Creepypasta tale, Butcher's Block tells the story of a young woman named Alice who moves to a new city and learns about a series of disappearances that may be connected to a baffling rumor about mysterious staircases in the city's worst neighborhoods. With help from her sister, they discover that something is preying on the city's residents."
This sounds a lot better than the fizzled dud, Channel Zero: No-End House (2017). Sure, it got off to a great start, what with some teens going into a reputed spook house that preys on your innermost fears and doesn't have an exit. But every slow-moving episode that followed felt like a no-end mini-series.
THE QUAKE (2018)
"In 1904 an earthquake of magnitude 5.4 on the Richter Scale shook Oslo, with an epicenter in the 'Oslo Graben', which runs under the Norwegian capital. There are now signs that indicate that we can expect a major future earthquake in Oslo."
You could almost predict this one — it's being done by the same folks who made the Norwegian hit disaster movie, The Wave (2015). Another prediction: Once The Quake comes out, they'll start working on The Really Windy Day, A Tree In the Road and The Pothole.
RISE OF THE LIVING DEAD (2018)
"In 1962, Dr. Ryan Cartwright was on the scientific and altruistic path to find a way for humans to sustain life in the event of M.A.D. (Mutual Assured Destruction), a huge topic brought on by the Cuban Missile Crisis. Little did he know that over the course of the next several years of his life, he would take a well-funded and military focused journey to the darkest corners of the world as he creates the ultimate weapon for the government and a curse that will plague mankind for the rest of days."
Cool title for YET ANOTHER zombie movie. Interesting to frame it around the Cuban Missile Crisis, which, I always thought was a near miss catastrophe about the Cuban cigar shortage. (Cigars are missile-shaped, hence, I assumed, the term.) Warning: this is what beer does to you.
Tropical Shark = Hawaiian Crunch
Posted in Classic Horror, Giant Monsters, Nature Gone Wild, Sharks with tags archipelago, biologist, Classic Horror, earthquake, Giant Monsters, Hawaii, Jaws, Nature Gone Wild, rum, Sharks, tourist, Up From The Depths on November 25, 2016 by Drinkin' & Drive-in
"There are no sharks in the Hawaiian archipelago!," screams a tropical hotel resort manager as his guests are being systematically eaten by a shark.
But it's not just any shark — this tourist trapper is a prehistoric shark, theorized to be let loose by an underwater earthquake. So believes the sea biologist, who later provides Up From The Depths' (1979) funniest moment. Besides all the other ones, that is.
Boaters, swimmers, divers and dumbasses are being attacked by said prehistoric predator, which isn't much bigger than Jaws' cousin's neighbor's BFF. One second you're there, the next, nothing but red, foamy bubbles. After a broad daylight attack, everybody leaves the water and runs back and forth on the beach, screaming and knocking over stuff. Then night falls. And the tourists are still screaming and running back and forth, knocking down stuff.
A reward for the monster is offered: a case of island rum. And to sweeten the pot (as if it was needed), the hotel manager throws in $1,000 bucks and a stay in the presidential suite. Well, dang — somebody hand me a spear!
The shark makes blurry cameos and his meals are about as graphic as watching somebody sloppily eating tomato soup. The aforementioned hilarity includes three drunk guys on a boat prepping a blow torch to go after the shark. (Flames under water — why didn't I think of that?) They end up turning their pleasure craft into a roaring campfire.
But the best LOL moment comes when the sea biologist barely makes it back aboard the boat after being attacked by the shark. In order to lure the beast out into the open, they tie a line around him, who just died from his injuries, and toss him into the drink. Then they tow his body back and forth in front of the hotel in front of the still screaming guests. What some people won't do for rum.
Plastic explosives are found, words were said, shark goes boom, all without actually seeing barely more than a dorsal fin and an occasional toothy smile. (Hawaiian sharks, like the islanders, are so pleasant.)
If you're looking for one of the worst Jaws (1978) knock-offs ever made, you just found it.
Sharks With Tan Lines
Posted in Nature Gone Wild, Sharks with tags bikini, Black & Decker, chain saw, earthquake, Goblin shark, lifeguard, Los Angeles, Malibu, Malibu Shark Attack, Nature Gone Wild, Sharks, skin diver, surfer, tsunami on November 18, 2016 by Drinkin' & Drive-in
Underwater earthquakes off the coast of California release a school of prehistoric sharks hell bent on eating anything wearing a bikini. And these Goblin sharks do a LOT of gobblin': surfers, skin divers, swimmers — anything that rhymes with food.
So what were the sharks doing for a million years while buried under the ocean? Playing cards, would be my guess. Probably Go Fish™. Don't give me that look — that joke was gold.
The earthquakes cause a tsunami, which obliterates those suns of beaches. In a genius move four lifeguards and two beachers make it into a lifeguard stand and ride out the Big Wave. Never mind that the lifeguard stand is basically painted balsa wood that manages to take a direct hit from the wave without snapping into toothpicks, or that the tsunami crushes everything else into jellyfish.
The survivors (for now) are trapped in the shelter with Goblin sharks skinny-dipping around them. Brilliant, I tell you. The sharks, unfortunately, meet their seafood destiny at the end of a Black & Decker™ chainsaw (B&D should use that in their marketing brochures.)
Goblin sharks have cartoonish protruding snouts, which look like novelty-store noses. Only thing missing is over-sized eye-glasses and squirting flowers on their lapels. They look stupid. Malibu Shark Attack (2009) is stupid. I'm stupid. Oh, yeah? Well, so are you. So there.
An Ode To Rubber Monsters
Posted in Asian Horror, Asian Sci-Fi, Fantasy, Giant Monsters, Godzilla, Science Fiction with tags Asian Horror, Asian Sci-Fi, earthquake, England, Fantasy, G8 Summit, Giant Monsters, Godzilla, Guilala, headphones, Japan, Japanese giant rubber monsters, Lord Take-Majin, mad scientist, magma, Monster X Strikes Back: Attack At The G Summit, pimento loaf, Polonium 20, Russia, Saran Wtap, Science Fiction, supermodel, The Pleasure Squad, United States on December 29, 2014 by Drinkin' & Drive-in
Monster X Strikes Back: Attack At The G Summit (2009) is a comedic homage to Japanese giant rubber monsters, though I fail to see the point about making fun of giant rubber monsters. I'm thinkin' oxymoron.
Nevertheless, world leaders have gathered for another windbag summit, right about the time Guilala – a giant creature with some Godzilla pointy things on his back, a horizontal flat face a horn and two perfectly straight antennae that probably gets all the channels – shows up to crash the party. The monster was brought back from outer space as spore and, when exposed to Earth's atmosphere, grew into the mega-tall dumbass he is today.
The G8 Summit leaders decide to help Japan from becoming a demolition derby. Japan fails with their use of controlling magma and earthquakes. Russia fails with Polonium 20, a poison so strong, it can kill anything. (Don't know what Russia's czar was thinking – I've eaten sandwiches that were more toxic.) England fails because, well, they're England. (Their plan was to drop giant headphones on Guilala and pipe in thought-disrupting frequencies. In the States we call that heavy metal.) Then someone gets a bright idea to cover Guilala in a huge sheet of Saran Wrap™ and pump pink-colored gas into his lungs.
The monster thinks their attempts are hysterical and laughs out loud. Time to call out the nuclear warhead, which may or may not kill Guilala. But everyone's fresh outta ideas. Fortunately, the villagers nearby do a song and dance routine to invoke the mighty Lord Take-Majin, a multi-armed golden deity who grows from a small statue holding a fire extinguisher and an umbrella, to equal size and weight of his opponent.
Take-Majin appears right as the nuke arrives – and sticks it right into his own golden rump. A momentary distraction as Take-Majin, um, shoves the missile all the way in and farts. Not making this up. I really wish I was. Guilala gets in a few good pops before Take-Majin cuts G's head off as though it were a pimento loaf. Japan is safe once again from itself.
There's some other stuff going on involving a supermodel news reporter and a mad scientist with a gang of giggling supermodels, called the Pleasure Squad. But don't let yourself get distracted or you won't be able to appreciate the subtle nuances of Guilala's ping-pong ball antennae.
A Monstrously Bad Monster
Posted in Aliens, Giant Monsters, Science Fiction with tags Cloverfield, documentary, earthquake, Giant Monsters, global-warming, Japan, Minister of Garbage, monster, Science Fiction on August 29, 2014 by Drinkin' & Drive-in
Monster (2008) is a Cloverfield (2008) knock-off so unbelievably bad, how anyone could claim writer's credit for this pile of film droppings is more unbelievable. Hell, it's not even good enough to be a rip-off.
Two American girls doing a hand-held camera documentary on global warming go to Japan to get their take on the whole pollution myth. While fumbling through an interview with the Minister of Garbage (great job title), a 7.5 earthquake rattles everyone's teeth. Then another and another. An ominous roar is heard reverberating throughout the city and you hear (but don't see) any buildings being destroyed, or more than three or four people in a city of eight million running for their lives.
This is the first 15 minutes. The rest of Monster is spent with the sisters trading the camera back and forth and crying, whining and checking their makeup. When the monster does show up (wiggling its patently fake rubber legs – less than 30 seconds total on-screen time), it's so horribly pathetic, you wanna kill your TV.
The DVD cover promised a 200-foot multi-tentacled creature flipping buildings over. This does not happen. What does happen is you get extremely pissed for having wasted $3.99 on something that looked like it was made by a sixth-grader. (Note to six-graders: Sorry about that, but you'll get your turn.)
More Godzilla Is Not Enough Godzilla
Posted in Asian Horror, Asian Sci-Fi, Classic Horror, Giant Monsters, Godzilla, Nature Gone Wild, Science Fiction with tags Asian Horror, Asian Sci-Fi, Classic Horror, earthquake, Gareth Edwards, Giant Monsters, Godzilla, Godzilla 2014, Nature Gone Wild, New York, San Francsico, time machine on February 21, 2014 by Drinkin' & Drive-in
It's painful enough to have to wait until the middle of May (2014) to see the new Godzilla movie. But now the film company is just being cruel to the point of sadistic by issuing another teaser poster, this time showing more of the Big Guy's new duds.
I can only beg and plead to whoever will put up with my begging and pleading (i.e., whining) that the scale of Godzilla in this poster is in correct proportion to the buildings he's about to turn into gravel soup. (G's a portable earthquake.)
Hard to tell what city this is, though it looks like San Francisco. Good – I'm tired of seeing New York getting all the fun. And New Yorkers just don't seem to appreciate a good monster stomping anymore since it has become just another day to them. I will NEVER become jaded watching giant monsters re-develop urban crapholes.
May 16, 2014. Anybody got a time machine I can borrow? I promise to bring it back yesterday.

redpajama_set_name: RedPajamaCommonCrawl


The MG2 is constructed using the latest manufacturing technologies allowing the maintenance of consistently tighter tolerances for all components. This new low weight standard pistol was designed and developed by Cesare Morini and can be considered the most innovative in the world.
Rigid case with instructions, tools, spare magazine etc.


text:
Q: XAML Menuitem Visibility Bound to another control or trigger isn't working Visibility="{Binding Path=Visibility, ElementName=btnUndo}"/>
I am trying to bind a menuitems visibility to another controls visibility (btnUndo).
That controls visibility is bound to a trigger
        <Style x:Key="undoStyle">
            <Style.Triggers>
                <DataTrigger Binding="{Binding SelectedItem.isEdited, ElementName=lvBatches}" Value="True">
                    <Setter Property="FrameworkElement.Visibility" Value="Visible"/>
                </DataTrigger>
                <DataTrigger Binding="{Binding SelectedItem.isEdited, ElementName=lvBatches}" Value="False">
                    <Setter Property="FrameworkElement.Visibility" Value="Collapsed"/>
                </DataTrigger>
            </Style.Triggers>
        </Style>

I tried binding the MenuItem to the same trigger, but that didn't work either.
Any suggestions?

A: ContextMenus exist in the Adorner Layer, which is not the same Visual Tree as the UI layer.
I know you can bind something like the following in a MenuItem, which will return the Control the ContextMenu is attached to, and from there you might be able to find the data you're looking for.
{Binding Path=PlacementTarget, RelativeSource=
     {RelativeSource FindAncestor, AncestorType={x:Type ContextMenu}}}

For example, you could create a Converter which traverses up the VisualTree from the specified control until it finds the object it's looking for, or you could bind to the DataContext and look for a specific value within your ViewModel.

redpajama_set_name: RedPajamaStackExchange


Drake Broadcasting System is Drake University's exciting hub for student broadcast on campus. Brought to you from our School of Journalism and Mass Communication, we exist to offer video coverage for campus events and experience for students looking to work in a real studio setting while at school.
Read more about our team and what we do.


THE internet was one of the greatest inventions of the 20th century – offering you an encyclopedia of information at the click of your fingertips. With this digital world at your fingertips, it has inevitably come with dangers.
While installing up-to-date internet security software on your computer or phone is the first step to protecting your data, there's plenty more you can do.
Here are a couple of tips to bear in mind. Firstly, get yourself educated. It's a big, wide, scary world on the internet, and your best chance is to learn about what you're up against.
Secondly, check your privacy settings. This seems really obvious, but so many people don't do it, or at least don't do it properly.
Thirdly, most of us are using one or more Google products. use. Hence it's no surprise Google decided to help its users be safer, easier, and has devised additional products ou can use free and whenever you need them.