text:
\section{Acknowledgements}

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\begin{document}
\title{Scintillation efficiency and ionization yield of liquid xenon
for mono-energetic nuclear recoils down to 4 keV

\author{A.~Manzur}
\author{A.~Curioni}
\altaffiliation[Current address: ]{Institute for Particle Physics, ETH Zurich, 8093 Zurich, Switzerland}
\author{L.~Kastens}
\author{D.N.~McKinsey}
\email[Corresponding author: ]{daniel.mckinsey@yale.edu}
\author{K.~Ni}
\altaffiliation[Current address: ]{Department of Physics, Shanghai Jiao Tong University, Shanghai, China}
\author{T.~Wongjirad}
\altaffiliation[Current address: ]{Department of Physics, Duke University, Durham, NC, USA}
\affiliation{Department of Physics, Yale
University, P.O. Box 208120, New Haven, CT 06520, USA}

\date{\today

\begin{abstract}
Liquid Xenon (LXe) is an excellent material for experiments designed
to detect dark matter in the form of Weakly Interacting Massive
Particles (WIMPs).  A low energy detection threshold is essential for a
sensitive WIMP search.  The understanding of the relative scintillation
efficiency ({\small $\mathcal{L}_\textrm{eff}$}) and ionization yield of low energy nuclear recoils
in LXe is limited for energies below 10 keV. In this paper,
we present new measurements that extend the energy down to 4 keV,
finding that {\small $\mathcal{L}_\textrm{eff}$}~ decreases with decreasing energy. We also measure the quenching of
scintillation efficiency due to the electric field in LXe, finding no
significant field dependence.
\end{abstract}

\pacs{95.35.+d, 29.40.Mc, 95.55.Vj

\maketitle

\section{Introduction}
Liquid xenon is increasingly used as the detection material in direct
searches for WIMP dark matter  \cite{Jungman:96}.  Recent developments in two-phase (gas/liquid)
xenon detectors \cite{Alner:07,Angle:08, Lebedenko:08} has resulted in stringent
limits on the WIMP-nucleon cross-section, constraining theories of
physics beyond the standard model, such as supersymmetry.
WIMPs will deposit a small amount of energy in the LXe through
elastic scatters with  xenon nuclei. Part of the
deposited energy is converted into observable signals of
scintillation light and ionization electrons. The rest of the energy
is converted into heat and can not be easily measured. Understanding
these effects  will help
determine nuclear recoil energies and ultimately play a part
in determining the WIMP-nucleon cross-section.

In a two-phase xenon detector, two signals are measured. The first is
the direct scintillation light, denoted as $S1$. The second is the
proportional scintillation light in the gas phase, denoted as $S2$,
which is proportional to the ionization electrons that survive
electron-ion recombination and are extracted into the gas.
Figure~\ref{fig:s1s2} gives an illustration of the signal production
and collection in a two-phase xenon detector.

For a given event in the LXe, the nuclear recoil energy can
be determined based on the scintillation signal $S1$
\cite{Alner:07,Angle:08}. However, it is much more convenient to calibrate the detector using
 electron recoil events. The tradition in the field  \cite{Arneodo:00,Akimov:02,Aprile:05,Chepel:06,Aprile:08} is to base the energy calibration on 122~keV electron recoils from a $^{57}$Co gamma source.
 The \textit{relative scintillation
efficiency}, {\small $\mathcal{L}_\textrm{eff}$}, defined as the ratio between the electron equivalent energy ($E_{ee}$) and the true nuclear recoil energy ($E_r$), becomes  necessary for determining the nuclear energy scale and, therefore, the WIMP detection sensitivity.
$E_{ee}$ is  inferred from the scintillation
signal yield  due to  monoenergetic electron recoils. {\small $\mathcal{L}_\textrm{eff}$}~ has no
units and is defined at zero electric field in LXe relative to 122~keV gamma rays.

If an electric field is applied to the LXe, the
scintillation yields for both electron and nuclear recoils are
suppressed by additional factors $S_e$ and $S_n$, respectively. The
relative scintillation efficiency can be calculated as
\begin{equation}
   \mbox{\fontsize{9}{11}\selectfont $\mathcal{L}_\textrm{eff}$}  = E_{ee}/ E_{r} \cdot S_e/S_n \\
\end{equation}
The quantity $S_e$ for 122~keV electron recoils from a $^{57}$Co
source has been  measured very accurately \cite{Aprile:06}.
$S_n$ has been measured for  56~keV nuclear recoils, with electric fields up to a few kV/cm
in LXe \cite{Aprile:06,Aprile:05}, but no measurement is available for
nuclear recoils at other energies.

\begin{figure}[htbp]
	\begin{center}
		\includegraphics[width=7cm]{fig/signal_01.pdf}
		\caption{(Color online) Illustration of the signal production and collection in a two-phase xenon detector.}
		\label{fig:s1s2}
	\end{center}
\end{figure}

Two methods have been utilized to determine {\small $\mathcal{L}_\textrm{eff}$}~ as a function of
energy: a) Using a fixed-energy neutron beam experiment, detecting
neutrons that scatter in the LXe
at a known scattering angle, and b) Comparing
neutron calibration data to Monte Carlo simulations without tagging
the scattered neutron.  Using method a), {\small $\mathcal{L}_\textrm{eff}$}~ has
been measured by a number of groups for nuclear recoils above 10~keV
\cite{Arneodo:00, Akimov:02, Aprile:05}.  There are also two
measurements of this type reporting results below 10~keV, one
suggesting an increasing {\small $\mathcal{L}_\textrm{eff}$}~ with decreasing energies
\cite{Chepel:06}, and another indicating a roughly constant {\small $\mathcal{L}_\textrm{eff}$}~ of $ 0.15$ down
to 5~keV \cite{Aprile:08}.  The XENON10 and the ZEPLIN-III
collaborations have also determined {\small $\mathcal{L}_\textrm{eff}$}~ with method b)
\cite{Sorensen:08, Sorensen:09, Lebedenko:08}.  In the XENON10 analysis, {\small $\mathcal{L}_\textrm{eff}$}~
does not decrease much at low energies, while in the ZEPLIN-III
measurement, the data imply a precipitous drop at low energies.

In this paper, we report on measurements of {\small $\mathcal{L}_\textrm{eff}$}~ at zero field and
$S_n$ at two different fields (0.73~kV/cm and 1.5~kV/cm) for nuclear
recoils between 4 and 66~keV in a single phase detector ($S1$-only).
We repeated these measurements using a dual phase detector ($S1$ and
$S2$ signals) at 1~kV/cm in the liquid and 10~kV/cm in the gas as well
as 4~kV/cm in the liquid and 8~kV/cm in the gas.  With the dual phase
detector we also measured the ionization signal yield for nuclear
recoils.  We present the experimental apparatus in
Section~\ref{sec:exp}, the data analysis in
Section~\ref{sec:analysis}, the results in Section \ref{sec:results},
a theoretical model of {\small $\mathcal{L}_\textrm{eff}$}~in Section \ref{sec:model} and a discussion
of the results in Section~\ref{sec:discussion}.

\section{Experimental Apparatus}
\label{sec:exp}

The measurement was performed with a setup comprising  a
deuterium-deuterium neutron generator \cite{Chichester:07}, a LXe
 detector, and an organic liquid scintillator detector, as shown
in Figure~\ref{fig:setup}. The neutron generator produces 2.8~MeV
neutrons at a rate of $10^6$ n/s. The liquid scintillator detector is
a BC501A organic scintillator module 3.8~cm in diameter and 3.8~cm in
height, viewed by a photomultiplier (PMT). Both the neutron generator
and the organic scintillator detector have previously been used to perform
measurements of nuclear recoils in liquid argon \cite{Lippincott:08}
and liquid neon \cite{Nikkel:08}. The LXe detector is made
of a cylinder of LXe viewed by two Hamamatsu R9869
 PMTs, as shown in Figure~\ref{fig:geant4_cell}.
The PMTs  are specially designed for LXe applications. They
have a bialkali photo-cathode and a quartz window with an aluminum
strip pattern on the photo-cathode.
The two PMTs have a  quantum efficiency of 36\% for
LXe scintillation light at 175~nm. The collection efficiency
from the photo-cathode to the first dynode is about 70\%. The active
LXe target is 5~cm in diameter and 2~cm in height and is surrounded
by polytetrafluoroethylene (PTFE) for UV light reflection. The
thickness of the PTFE is minimized (11.5~mm) to reduce neutron multiple scatters
with surrounding materials. Two stainless steel mesh grids, each with 90\%
optical transparency, are installed to apply  electric field to the
LXe. In dual phase mode, a third grid is added to apply a separate
electric field in the xenon gas region.

The LXe detector is
located in an aluminum vacuum cryostat and cooled by a pulse-tube
refrigerator (PTR). The cryogenic system is described
elsewhere \cite{Ni:07}. The neutron generator is shielded by
30.5~cm~$\times$~30.5~cm~$\times$~30.5~cm water boxes  and two 10~cm $\times$ 30~cm $\times$ 30~cm polyethylene slabs to block and absorb neutrons that are emitted in directions other than toward the cryostat.
The distance from the neutron generator to the center of the LXe was 76~cm. The distance between the center of the LXe and the center of the organic scintillator varied from 16 to 20~cm between runs. The scattering angle, defined by the position of the organic scintillator (Figure \ref{fig:setup}), was varied from 25 to 125 degrees to vary the associated recoil energy.

\begin{figure}[htbp]
	\begin{center}
		\includegraphics[width=8cm]{fig/setup_02.pdf}
		\caption{(Color online) The setup for nuclear recoil scintillation efficiency
		measurement in LXe. Not drawn to scale.}
		\label{fig:setup}
	\end{center}
\end{figure}

\begin{figure}[htbp]
	\centering
		\includegraphics[width=8.0cm]{fig/Cell_dual_03.pdf}
	\caption{(Color online) Schematic of the dual phase LXe detector. Spaces
	not drawn were filled with PTFE pieces. PMTs, LXe and xenon gas
	regions drawn to scale.}
	\label{fig:geant4_cell}
\end{figure}

During the single phase runs, the PMT waveforms  were recorded with an 8-bit oscilloscope, model TDS-5034B from Tektronix. The oscilloscope's logic gate was used to trigger the data acquisition system,
triggering on triple coincidence (both $S1$ signals and the organic scintillator signal) in a 80~ns window.

For the dual phase runs, a VME 12-bit, 250 MS/s digitizer (CAEN V1720)  was used, because of its higher dynamic range. An external trigger for the VME digitizer was generated using external NIM modules.
In this mode the data acquisition system was triggered by the $S2$ signals. At a few scattering angles, data acquisition was instead triggered by the $S1$ signals to test for any systematic effects due to the trigger.
For the $S2$ trigger,  shown in Figure \ref{fig:Dual_DAQ}, the PMT signals were added and integrated using a FAN IN/OUT and an integrator module. The summed and integrated signal then went to a discriminator  to select the $S2$ signals. The scintillator signal was sent through a discriminator to avoid small pulses. The output signal was used to generate a 15~$\mu$s pulse with the help of a gate generator. This pulse in coincidence with the $S2$ pulse generated the trigger for the acquisition system. For the $S1$ trigger we reproduced the trigger system described above for single phase operation, but using NIM modules.
In both the single and dual phase runs, the data were recorded  at a rate of $\sim$5~Hz.

\begin{figure}[htbp]
	\centering
		\includegraphics[width=3.25in]{fig/Dual_DAQ_04.pdf}
	\caption{(Color online)
	Trigger system used in the dual phase runs. The PMT signals are summed and integrated to select
	the $S2$ signals. The organic scintillator signal generates a 15 $\mu$s pulse. This pulse and the
	$S2$ signals in coincidence trigger the acquisition system. For the single phase runs, triple
	coincidence of the $S1$ signals and the organic scintillator signal triggers the acquisition system.}
	\label{fig:Dual_DAQ}
\end{figure}

Throughout the runs, periodic calibrations were performed to test the stability of the PMTs and measure the purity of the LXe.
The gains of the two PMTs were measured from the single photoelectron
(pe) spectra by using light emitted from a blue LED located inside
the LXe detector. The energy scale is calibrated using
122~keV gamma rays from a $^{57}$Co source located outside the
cryostat. The scintillation signal yields for the 122~keV gamma rays
in LXe in the single phase detector are  $10.8
\pm 0.1$ pe/keVee (keV in electron equivalent) at zero field and $4.8
\pm 0.1$ pe/keVee at 1.5 kV/cm (Figure~\ref{fig:co57}).
After adding a third grid and PTFE spacer and then removing some LXe to run the dual
phase mode, the light yield drops to $9.5 \pm 0.2$~pe/keVee at zero
field and $4.3 \pm 0.1$~pe/keVee at 1.0~kV/cm drift field. The
light yields from the 122~keV events were monitored over the entire
period of the measurements finding an additional fluctuation less than 3\%.
\begin{figure}[htbp]
	\begin{center}
		\includegraphics[width=5.5cm, angle=90]{fig/co57_s1_05.pdf}
		\caption{(Color online) Scintillation light yield for 122~keV gamma rays in the
		LXe detector running in single phase.
		The left histogram was taken at 1.5~kV/cm yielding $4.8
		\pm 0.1$~pe/keVee and a resolution ($\sigma/E$) of 18\%. The right
		histogram was taken at 0.0~kV/cm yielding $10.8 \pm 0.1$~pe/keVee
		and a resolution of 8.8\%.}
		\label{fig:co57}
	\end{center}
\end{figure}

During the single phase runs, the LXe purity was monitored by
measuring the stability of the scintillation signal yield from 122 keV
gamma rays. During the dual phase runs, the purity was also monitored
by measuring the electron lifetime, $\tau$, found by fitting the $S2$
spectrum with $S2 = S2_0 \exp{[-dt/\tau]}$ where $dt$ is the
electron drift time, measured as the time between the $S1$ and $S2$
signals. For the data presented here, electron lifetime was
greater than 40~$\mu$s and continuously improved over the course of the experiment.
By the end of the experiment, the electron lifetime
was 90 $\mu$s.
The total drift time for events at the cathode grid is  12 $\mu$s.
The $S2$ signals were corrected for the electron
lifetime. Figure \ref{fig:co57_s2} shows a typical $S2$ spectrum
for 122~keV gamma rays taken during the dual phase runs.

\begin{figure}[htbp]
	\centering
		\includegraphics[width=5.5cm, angle=90]{fig/co57_s2_1_06.pdf}
	\caption{$S2$ spectrum for 122~keV gamma rays in the dual phase detector.}
	\label{fig:co57_s2}
\end{figure}

\section{Finding  { $\mathcal{L}_\textrm{EFF}$} }
\label{sec:analysis}

To obtain the {\small $\mathcal{L}_\textrm{eff}$}~ value for each experimental setup we take the following steps. First, apply a set of cuts to reduce uninteresting events such as noise events, gamma ray scatters, neutron inelastic scatters and multiple elastic scatters. Next, the energy spectrum is obtained based on the light yield measurements and fitted to a  spectrum predicted through Monte Carlo simulation. The following subsections explain these steps.

\subsection{Data Analysis}
\label{sec:data_analysis}
To remove uninteresting events two sets of cuts were used. The first set
removes noise events and events outside the energy window of interest.
The second set consists of two  cuts  used to select single elastic
nuclear recoil events (Figure~\ref{fig:psdtof}):
\begin{itemize}
	\item The first cut is based on
	the pulse shape discrimination (PSD) of the organic scintillator. The
	PSD is
	 based on the relation between pulse height and pulse area.
	This  is an effective way to separate the neutron events from gamma
	events in the organic scintillator.
	\item The second cut uses the fact that
	neutrons take a longer time to travel from the LXe detector to the
	organic scintillator than gamma rays. The cut uses the time of flight
	(ToF) to remove events triggered by gamma rays or
	accidental coincidence. The cut selects the first half of the ToF peak because the contribution from scatters other than single elastic ones is negligible, as determined from Monte Carlo simulations.
\end{itemize}

\begin{figure}[htbp]
	\begin{center}
	$\begin{array}{c}
			\includegraphics[width=5.5cm, angle=90]{fig/PSD_v2_07a.pdf} \\
			\includegraphics[width=5.5cm, angle=90]{fig/TOF_v2_07b.pdf} \\
	\end{array}	$
		\caption{(Color online) Two cuts used in the analysis to select single scatter
		nuclear recoil events. \textbf{(a)} pulse shape discrimination in
		the organic scintillator. \textbf{(b)} neutron time of flight
		between the LXe and the organic scintillator.
		Both plots show experimental data for 56~keV$_\textrm{r}$~run.}
		\label{fig:psdtof}
	\end{center}
\end{figure}

  The nuclear recoil energy distributions
($S1$ signals) after these two cuts are shown in
Figures~\ref{fig:S1S2_signals} \textbf{(a)} and \textbf{(b)}
for 6 keV$_\textrm{r}$~ nuclear recoils at zero electric field and 66 keV$_\textrm{r}$~ nuclear recoils at 1.5 kV/cm, respectively. Similarly, Figures ~\ref{fig:S1S2_signals} \textbf{(c)} and \textbf{(d)} show $S2$ distributions for 6 keV$_\textrm{r}$~nuclear recoils at zero electric field and 66
keV$_\textrm{r}$~ nuclear recoils at 1.5 kV/cm, after the cuts.
In the 56 and 66~keV$_\textrm{r}$~runs it is easy to separate the background tail from the single elastic signal, as shown in Figure \ref{fig:S1S2_signals} \textbf{(b)}. This tail has been removed ($S1 < 50$ pe) to generate the $S2$ spectrum in Figure \ref{fig:S1S2_signals} \textbf{(d)}, and to find the {\small $\mathcal{L}_\textrm{eff}$}~values.

\begin{figure*}[htbp]
	\centering
	$\begin{array}{cc}
		\includegraphics[width=5.9cm, angle=90]{fig/S1_6_08a.pdf} &
		\includegraphics[width=5.9cm, angle=90]{fig/S1btail_56_08b.pdf} \\

		\includegraphics[width=5.9cm, angle=90]{fig/S2_6kevr_08c.pdf} &
		\includegraphics[width=5.9cm, angle=90]{fig/S2_56kevr_08d.pdf} \\
	\end{array}$

	\caption{$S1$ spectra in pe for \textbf{(a):} 6~keV$_\textrm{r}$~
	nuclear recoils at zero electric field and \textbf{(b):} 66~keV$_\textrm{r}$~ nuclear recoils at 1.5 kV/cm,
	after applying the cuts.
	$S2$ spectra in pe for \textbf{(c):} 6~keV$_\textrm{r}$~
	nuclear recoils at zero electric field and \textbf{(d):} 66~keV$_\textrm{r}$~ nuclear recoils at 1.5 kV/cm.}
	\label{fig:S1S2_signals}
\end{figure*}

\subsection{Monte Carlo simulation}
\label{sec:mc}
The detector's response to neutrons is modeled using a Geant4
\cite{Geant4:03} simulation that takes into account the realistic setup
of the experimental apparatus as described in Section~\ref{sec:exp},
including the water shield around the neutron generator, the
polyethylene shield around the organic scintillator detector, the
aluminum cryostat, the stainless steel cell, PTFE structure, PMTs,
grids and LXe in the detector. The simulation stores the neutron
scattering position, time, energy and type of events that deposit
energy in both the LXe detector and the liquid scintillator.

For the simulations we follow the work by \cite{Sorensen:09} and used
 the Xe(n,n)Xe scattering cross-sections from the updated ENDF/B-VII data, instead of the ENDF/B-VI cross-section used by default with the software. As discussed in \cite{Pignil:07}, a $\pm3\%$ uncertainty associated to the well depth parameter in the Optical Model Potential used to calculate the elastic cross-sections, leads to a conservative uncertainty which translates into an
  uncertainty up to $\pm3\%$  in the nuclear recoil spectra. The latter is included when calculating the {\small $\mathcal{L}_\textrm{eff}$}~ systematic uncertainty.

Neutrons can
deposit energy in LXe via  elastic scattering, inelastic scattering,
or a mixture of both. For most of the events that satisfy the ToF cut
between the LXe and the liquid scintillator,  neutrons come directly
from the neutron generator, make a pure single elastic scatter in LXe and
reach the liquid scintillator.

Single elastic events
give a peak (see Figure~\ref{fig:n_sim}) at the energy $E_r$
determined by the kinematics according to:
\begin{equation}
\label{eq:kin}
E_r \approx E_n \frac{2m_n m_{Xe}}{(m_n + m_{Xe})^2} (1-\cos{\theta})
\end{equation}
where $E_n$ is the incoming neutron energy (2.8~MeV), while $m_n$ and
$m_{Xe}$ are the masses of the neutron and the Xe nucleus, and $\theta$ is
the scattering angle. The spread of the energy deposition peak is
from the  spread of $\theta$ due to the geometric width of the LXe
detector,  the width of the organic scintillator and the distance between
them.

Some of the neutrons from the generator may scatter first in other
materials (e.g. PTFE) before entering the LXe detector. Neutrons may also
scatter more than once in the LXe detector. These ``multiple-scattering"
events have a variety of scattering angles and, therefore, deposit a wider range
of energies than the single elastic scatters. This contributes to the background tail under the
pure single scattering peak.
Through minimization of non-active material, the geometry of the detector was designed
to reduce background from multiple scattering events, especially for runs performed
at low scattering angles.
Inelastic scattering events are very few and
make negligible contribution to the energy spectrum (less than 1\%).
A detailed description of the contributions of each background for
each energy tested can be found in \cite{Manzur:09}.

\begin{figure}[htbp]
	\begin{center}
			\includegraphics[width=6.cm, angle=90]{fig/Emc_25_v2_09a.pdf}
			\includegraphics[width=6.cm, angle=90]{fig/Emc_40_v2_09b.pdf}
			\includegraphics[width=6.cm, angle=90]{fig/Emc_125_v2_09c.pdf}
		\caption{(Color online) Simulated distribution of energy deposition in the LXe for
			2.8~MeV neutrons that scatter and are tagged by the organic
			 scintillator, for three different angles, assuming the same ToF cuts
			 that were used in the experimental data. The solid line corresponds to all
			types of events, the blue dashed line to single elastic nuclear recoils,
			and the purple dotted line to multiple elastic scatters.
			Multiple scatter events and inelastic events  are
			negligible compared to the single scatter events. The energy and
			uncertainty values indicated in the figure legends
			are based on the mean and variance (one sigma) of
			 the peak for all events.}
		\label{fig:n_sim}
	\end{center}
\end{figure}

Although the LXe detector gives a high scintillation yield,
detecting and resolving the peak for low energy nuclear
recoils is still challenging.
The energy spread for nuclear recoils
below 10 keV$_\textrm{r}$~ is dominated by statistical fluctuation of the
photoelectrons in the PMTs. The trigger threshold,  the trigger
efficiency and the $S1$-finding algorithm efficiency  must be taken
into account in the analysis since not all events are effectively
detected. In our measurement, the trigger of the LXe signal is from
coincidence of the two PMTs with leading-edge discriminators.
Effects of the trigger and software efficiencies are included in the
Monte Carlo spectrum.
A realistic model of the trigger efficiency was determined by a Monte Carlo simulation that included
photon distribution into the two PMTs, quantum
efficiencies,
statistical sampling of typical noise and single photoelectron  waveforms in the PMTs,
the electronic trigger
thresholds, and the  $S1$-finding algorithm in the analysis software.
Figure~\ref{fig:s1_finding_eff} shows the overall trigger efficiency
when combining these effects.

\begin{figure}[htbp]
	\centering
		\includegraphics[width=6cm, angle=90]{fig/s1_finding_eff_10.pdf}
	\caption{(Color online)  Detector triggering and software efficiencies for the
	single (\textcolor{green}{\ding{115}}) and dual phase
	(\textcolor{blue}{\ding{108}}) runs. The \textcolor{red}{\ding{110}}
	points show the ideal case when the PMTs and the software have 100\%
	efficiency for a single photoelectron.}
	\label{fig:s1_finding_eff}
\end{figure}

For each energy studied, the {\small $\mathcal{L}_\textrm{eff}$}~ value is found by comparing the
Monte Carlo generated spectrum with the measured spectrum, using a
$\chi^2$ test  according to equation \cite{PDG:06}:
\begin{equation}
\label{eq:chisq}
\chi^2 = \sum^N_{i=1} \frac{(n_i - \nu_i)^2}{\nu_i}
\end{equation}
where  $N$ is the
total number of bins, while $n_i$ and $\nu_i$ are the measured and
Monte Carlo generated number of events in each energy bin.
To perform the $\chi^2$ test, the total number of events in the Monte Carlo
spectrum was normalized to that of the measured spectrum.
The energy
distribution (or $\nu_i$ at different energy bins) from the Monte
Carlo spectrum varies with different input of {\small $\mathcal{L}_\textrm{eff}$}~ values. The
best-fit {\small $\mathcal{L}_\textrm{eff}$}~ value is obtained by minimizing the $\chi^2$ parameter.
Figures~\ref{fig:mc_leff}	\textbf{(a)} and \textbf{(b)} show the data (points with error bars)
and the Monte Carlo spectrum (line) after minimization, for 6 keV$_\textrm{r}$~ nuclear recoils at zero electric field and 66 keV$_\textrm{r}$~
nuclear recoils at 1.5 kV/cm. These plots correspond to the $S1$ spectra shown in Figures~\ref{fig:S1S2_signals} \textbf{(a)} and \textbf{(b)}.
Figures~\ref{fig:mc_leff}	\textbf{(c)} and \textbf{(d)} show the $\chi^2$ vs. {\small $\mathcal{L}_\textrm{eff}$}~ histograms.

\begin{figure*}[htbp]
	\centering
	$\begin{array}{c@{\hspace{.0in}}c}
		\includegraphics[width=5.9cm, angle=90]{fig/S1_6_MC_11a.pdf} &
		\includegraphics[width=5.9cm, angle=90]{fig/S1_56_MC_11b.pdf} \\

		\includegraphics[width=5.9cm, angle=90]{fig/6_leff_11c.pdf} &
		\includegraphics[width=5.9cm, angle=90]{fig/56_leff_11d.pdf} \\
	\end{array}$
	\caption{(Color online) $S1$ measured spectrum (data points) and Monte Carlo comparisons (solid line) for \textbf{(a)} 6~keV$_\textrm{r}$~ nuclear recoils at zero electric field and \textbf{(b)} 66 keV$_\textrm{r}$~ nuclear recoils at 1.5 kV/cm. The background tail ($S1 < 50$ pe) for the 66 keV$_\textrm{r}$~ run has been removed for the $\chi^2 $ test.
	Also shown are the $\chi^2$ vs {\small $\mathcal{L}_\textrm{eff}$}~ histograms for \textbf{(c)} 6~keV$_\textrm{r}$~nuclear recoil at zero electric field and \textbf{(d)} 66 keV$_\textrm{r}$~nuclear recoils at 1.5 kV/cm. The points show the different {\small $\mathcal{L}_\textrm{eff}$}~ values tested while the  curve is a fit to the points used to find the 1$\sigma$ errors on the {\small $\mathcal{L}_\textrm{eff}$}~ value. }
	\label{fig:mc_leff}
\end{figure*}

\section{Results}
\label{sec:results}
The largest  uncertainties in {\small $\mathcal{L}_\textrm{eff}$}~ derive from the $\chi^2$ analysis
and from the energy resolution applied to the Monte Carlo spectrum.
The energy resolution is a combination of Poisson fluctuations in the PMTs,
 the PMT gain fluctuations, the
geometry of the cell ($\sigma_{geo}$), the optical properties of the
materials  and the intrinsic resolution of the
LXe. The total energy resolution, $\sigma$, defined
as the root mean squared of the terms mentioned, was measured to be
$\sigma = (3.2 \pm 0.4) \sqrt{N}$ with $N$ the number of
photoelectrons for 56 and 66 keV$_\textrm{r}$. This relationship was assumed for
determining all {\small $\mathcal{L}_\textrm{eff}$}~ values.
Because the geometry resolution is already included in the simulation, the Monte Carlo data
were convolved using an  energy resolution $\sigma' \equiv \sqrt{\sigma^2
- \sigma_{geo}^2}$.
The gain fluctuations were measured from the calibration
runs, while the error due to the optical properties was determined from an independent light
simulation. After subtracting the geometry resolution, the overall uncertainty on $\sigma'$  is
estimated to be $\pm 1.0 \sqrt{N}$, and this is propagated through to compute
the systematic uncertainty in {\small $\mathcal{L}_\textrm{eff}$}. The total  errors are shown in Figure~\ref{fig:leff_result} and given in Table \ref{tab:leff_vals}.  Figures~\ref{fig:leff_result} and \ref{fig:results_finalMC} compare
our {\small $\mathcal{L}_\textrm{eff}$}~ results with previous analyses. Since the data show no
significant nuclear quenching due to the electric field, {\small $\mathcal{L}_\textrm{eff}$}~ is
computed using data from all of the different runs, regardless of
electric field.

\begin{figure}[htbp]
	\begin{center}
		\includegraphics[width=5.5cm, angle=90]{fig/results_final_er4_12.pdf}
		\caption{(Color online) Scintillation efficiency for nuclear recoils relative to
		that of 122 keV gamma rays in LXe at zero field, comparing
		this work (\textcolor{DarkBlue}{$\medbullet$}) to previous
		measurements from Arneodo (\textcolor{black}{$\bigtriangleup$})
		\cite{Arneodo:00}, Akimov (\textcolor{DarkGreen}{$\Box$})
		\cite{Akimov:02}, Aprile (\textcolor{blue}{\ding{73}})
		\cite{Aprile:05}, Chepel
		(\textcolor{red}{$\Diamond$}) \cite{Chepel:06} and Aprile (\textcolor{DarkRed}{$\bigcirc$})\cite{Aprile:08}. Also shown is the
		theoretical model (dashed line) explained in Section~\ref{sec:model},
		which includes the Lindhard factor, an electronic quenching
		due to bi-excitonic collisions and the effect  of escaping electrons.}
		\label{fig:leff_result}
	\end{center}
\end{figure}

\begin{figure}[htbp]
	\centering
		\includegraphics[width=5.5cm, angle=90]{fig/results_finalMC_er4_13.pdf}
	\caption{(Color online) Scintillation efficiency for nuclear recoils measured in
	this work (\textcolor{DarkBlue}{$\medbullet$}) and the theoretical
	model (dashed line) compared to the scintillation efficiency found
	from the neutron calibration data by the XENON10 (top shaded area) \cite{Sorensen:09}
	and the ZEPLIN-III (bottom shaded area) \cite{Lebedenko:08} collaborations.}
	\label{fig:results_finalMC}
\end{figure}

An electric field applied to LXe will suppress electron-ion
recombination and thus reduce the scintillation yield. This field
induced quenching is significant for electronic recoils. For example,
at 1~kV/cm, scintillation light yield from 122~keV gamma rays in
LXe is reduced to 53\% of its value at zero field
\cite{Aprile:05}. For nuclear recoils, a near-unity value of $S_n$
 has been measured at 56~keV$_\textrm{r}$ \cite{Aprile:05, Aprile:06}.
Here we measured the field induced quenching for nuclear recoils as low in energy as 4
keV$_\textrm{r}$. No significant field
quenching was observed for any energy or electric field. The average
field induced quenching factor, $S_n$, for 56 keV$_\textrm{r}$~nuclear recoils at an
electric field of 0.73 kV/cm  is about 95\% as given in Table~\ref{tab:leff_vals}.

From the dual phase data we can determine the ionization yield
(number of electrons escaping recombination per unit recoil energy).
This number is determined from the $S2$  peak position for the
nuclear recoils (Figure~\ref{fig:S1S2_signals}\textbf{(d)} for example) and the
number of photoelectrons per electron determined from the $^{57}$Co
calibration runs.
Figure \ref{fig:QEQ0} shows the energy dependence of the ionization
yield measured in this work for 1.0~kV/cm and 4.0~kV/cm, as well as
previous measurements \cite{Aprile:06} and the calculated values when comparing the XENON10 nuclear recoil data and Monte Carlo simulations \cite{Sorensen:09}.
The ionization yield errors shown in Figure \ref{fig:QEQ0} were derived from the
width of the $S2$ signals from nuclear recoils and from the $^{57}$Co calibrations.
By comparing the dual phase runs
triggered by the $S1$ signals with the runs triggered by the $S2$ signals, we determined that there is no significant uncertainty in the $S2$ signals due to the trigger.

\begin{figure}[htbp]
	\centering
		\includegraphics[width=6.0cm, angle=90]{fig/QEQ0_2_14.pdf}
	\caption{(Color online)  Ionization yield as a function of recoil energy. Shown are
	the measured values in this work at 1.00~kV/cm
	(\textcolor{DarkBlue}{\ding{115}}) and 4.00~kV/cm
	(\textcolor{red}{$\medbullet$}), along with previously measured
	values at 0.10~kV/cm (\textcolor{black}{$\bigcirc$}), 0.27~kV/cm (\textcolor{red}{$\Box$}), 2.00~kV/cm
	(\textcolor{blue}{$\bigtriangleup$}) and
	2.30~kV/cm(\textcolor{black}{$\Diamond$}) from \cite{Aprile:06},
	error bars  omitted for clarity. Also shown are the ionization yields calculated by comparing
	the XENON10 nuclear recoil data and the Monte Carlo simulations \cite{Sorensen:09}
	for single  elastic recoils at 0.73~kV/cm, using two different methods (\textcolor{blue}{\ding{83}} and
	\textcolor{DarkGreen}{\ding{73}}).
	}
	\label{fig:QEQ0}
\end{figure}

\begin{table*}
	\caption{{\small $\mathcal{L}_\textrm{eff}$}~and $S_n$ values  for the different
	nuclear recoil energies studied. The third   column gives the {\small $\mathcal{L}_\textrm{eff}$}~values relative to
	122 keV gamma rays. The first error is the statistical uncertainty, and the second error is the systematic uncertainty.} \label{tab:leff_vals}
\begin{center}
\begin{tabular}{cc|c|cccc}
 &  $E_r$ & {\small $\mathcal{L}_\textrm{eff}$}~  & $S_n$  & $S_n$ & $S_n$ & $S_n$ \\
$\theta$	&  [keV$_\textrm{r}$]	& at 0.0~kV/cm   & 0.73~kV/cm & 1.0~kV/cm & 1.5~kV/cm & 4.0~kV/cm\\
\hline \hline
125 &	66.7	$\pm$	3.3	&	0.178	$^{+	0.018 	+	0.010}_{-	0.016	-	0.009}$
	&	0.91	$\pm$	0.07	& 	1.11	$\pm$	0.09	&	0.88	$\pm$	0.06	&	-	\\ [1ex]
110 &	57.7	$\pm$	3.2	&	0.182	$^{+	0.009 	+	0.004}_{-	0.009	-	0.002}$
	& 	0.95	$\pm$	0.05	&	0.95	$\pm$	0.06	&	0.93	$\pm$	0.04	& 0.93	$\pm$	0.06	\\ [1ex]
95 &	46.1	$\pm$	4.9	&	0.158	$^{+	0.038	+	0.010}_{-	0.039	-	0.009}$
	&	0.97	$\pm$	0.08	& - &	0.82	$\pm$	0.08	& - \\ [1ex]
80 &	34.9	$\pm$	2.1	&	0.133	$^{+	0.042	+	0.014}_{-	0.029	-	0.012}$
	&	1.33	$\pm$	0.26	& - &	1.30	$\pm$	0.25	& - \\ [1ex]
67 &	25.7	$\pm$	2.0	&	0.132	$^{+	0.025	+	0.001}_{-	0.019	-	0.006}$
	&	0.95	$\pm$	0.06	&	0.91	$\pm$	0.12	& 0.95	$\pm$	0.07	& - \\ [1ex]
58 &	19.6	$\pm$	2.6	&	0.157	$^{+	0.046	+	0.008}_{-	0.036	-	0.019}$
	&	0.70	$\pm$	0.06	& - &	1.03	$\pm$	0.13	& - \\ [1ex]
50 &	15.1	$\pm$	1.5	&	0.123	$^{+	0.030	+	0.019}_{-	0.023	-	0.014}$
	&	0.83	$\pm$	0.16	&	1.02	$\pm$	0.20	&	1.01	$\pm$	0.15	& 1.08	$\pm$	0.18\\ [1ex]
40 &	9.8	$\pm$	1.3	&	0.118	$^{+	0.027	+	0.029}_{-	0.022	-	0.022}$
	&	0.91	$\pm$	0.17	&	1.64	$\pm$	0.50 	&	0.98	$\pm$	0.18	& 1.62	$\pm$	0.45\\ [1ex]
35 &	7.6	$\pm$	1.2	&	0.105	$^{+	0.028	+	0.026}_{-	0.022	-	0.029}$
	&	0.79	$\pm$	0.28	&	1.06	$\pm$	0.30	&	0.79	$\pm$	0.28	& - \\ [1ex]
32 &	6.4	$\pm$	1.1	&	0.094	$^{+	0.027	+	0.023}_{-	0.022	-	0.029}$
	&	0.92	$\pm$	0.37	&	1.25	$\pm$	0.45	&	0.93	$\pm$	0.38	& 1.38	$\pm$	0.52\\ [1ex]
30 &	5.7	$\pm$	1.1	&	0.077	$^{+	0.028	+	0.027}_{-	0.022	-	0.026}$
	&	1.35	$\pm$	0.67	& - &	1.18	$\pm$	0.61	& - \\ [1ex]
28 &	4.9	$\pm$	0.9	&	0.088	$^{+	0.026	+	0.026}_{-	0.023	-	0.032}$
	&	1.16	$\pm$	0.45	&	1.34	$\pm$	0.50	&	0.87	$\pm$	0.35	& - \\ [1ex]
25 &	3.9	$\pm$	0.9	&	0.073	$^{+	0.034	+	0.018}_{-	0.025	-	0.026}$
	&	1.19	$\pm$	0.52	&	1.30	$\pm$	0.38	&	1.88	$\pm$	0.78	& - \\ [1ex]
\hline

\end{tabular}
\end{center}
\end{table*}

\section{Empirical model of { $\mathcal{L}_\textrm{EFF}$}}
\label{sec:model}
The data shown above reveal a relative scintillation efficiency that
decreases with decreasing energy. A suitable theoretical expression for
{\small $\mathcal{L}_\textrm{eff}$}~ in LXe can be written as the product of at least three components:

\begin{equation}
\label{eq:totqf}
  \mbox{\fontsize{9}{11}\selectfont $\mathcal{L}_\textrm{eff}$}  = q_\textrm{ncl} \cdot q_\textrm{esc} \cdot q_\textrm{el}
\end{equation}

First is the Lindhard factor \cite{Lindhard:63},
$q_\textrm{ncl}$, which quantifies the larger fraction of energy dissipated
into atomic motion or heat in a nuclear recoil compared to that for
an electron recoil. As a function of recoil energy, $E_r$, the Lindhard factor
can be written as
\begin{equation}
	\label{eq:qncl}
		q_\textrm{ncl} = \frac{k\cdot g(\varepsilon)}{1 + k \cdot g(\varepsilon)}
\end{equation}
where for a nucleus with atomic number $Z$ and mass number $A$,
$k = 0.133 \cdot Z^{2/3} \cdot A^{-1/2}$,
$g(\varepsilon) = 3.0 \varepsilon^{0.15} + 0.7 \varepsilon^{0.6} + \varepsilon$,
 where $\varepsilon$ is the reduced energy $\varepsilon = 11.5 \cdot E_r \cdot Z^{-7/3}$.

The second term, $q_\textrm{esc}$, is the reduction of the scintillation light yield due to
\emph{escaping electrons}. These  are electrons
produced by ionization that thermalize outside the Onsager radius and
become free from recombination even in the absence of an electric field
\cite{Doke:02}.  The effect of escaping electrons has been observed for
electron recoils
\cite{Doke:02} and
 has only recently been
considered as a possible additional factor governing the total
scintillation reduction for nuclear recoils in LXe
\cite{Shutt:pri}. This is because of the surprisingly high ionization yield from
nuclear recoils \cite{Aprile:06}. This factor can be expressed in
terms of the ratio between the initial number of excitons
and electron-ion pairs $\alpha \equiv N_\textrm{ex}/N_\textrm{i}$, and  the
fraction of escape electrons over the total electron-ion pairs $\beta \equiv N_\textrm{esc}/N_\textrm{i}$.
\begin{equation}
q_\textrm{esc} = \frac{N_\textrm{ex} + N_\textrm{i} -
N_\textrm{esc}}{N_\textrm{ex} + N_\textrm{i} - N_\textrm{esc}^{122}}
=  \frac{\alpha +  1- \beta_{\textrm{NR}}}{\alpha + 1 - \beta^{122}}
\end{equation}
For this work we select
$\alpha = 0.06$, measured for electron recoils in LXe \cite{Doke:02, Dahl:09-phd}.
$\beta^{122}$ is the fraction of escaping electrons for 122~keV
electron recoils in LXe and is calculated to be 0.31 based on the
$^{57}$Co data from \cite{Aprile:06} and the method described in \cite{Doke:02}.
$\beta_{\textrm{NR}}$ can be calculated based on
the nuclear recoil ionization yield reported in \cite{Aprile:06}
and those measured in this work (Figure~\ref{fig:QEQ0}). The $\beta_{\textrm{NR}}$
values estimated for the different energies studied in this work are
given in Figure \ref{fig:Nesc_mine_kevr}.

\begin{figure}[htbp]
	\centering
		\includegraphics[width=6cm, angle=90]{fig/Nesc_mine_kevr_log_a06_15.pdf}

	\caption{Fraction of escape electrons for nuclear recoils, $\beta_{\textrm{NR}}$,  as a function of
	recoil energy used in this work.}
	\label{fig:Nesc_mine_kevr}
\end{figure}

The last term in the {\small $\mathcal{L}_\textrm{eff}$}~model is the scintillation light quenched
by  bi-excitonic collisions, $q_\textrm{el}$, as proposed by Hitachi
\cite{Hitachi:05} to explain the much lower measured {\small $\mathcal{L}_\textrm{eff}$}~ values
 than are predicted by $q_{\textrm{ncl}}$ alone.
Bi-excitonic collisions have the effect of two excitons producing a
single photon instead of two photons. A recent paper \cite{Mei:08}
extends the study of quenching due to bi-excitonic collision by
including the varying quenching due to different stopping power for
different energy recoils, as quantified by Birks' Law \cite{Birks:51}. Thus,
\begin{equation}
q_\textrm{el} = \frac{1}{1 + k_{B} \cdot \frac{dE}{dx}}
\end{equation}
We obtain $dE/dx$ values from SRIM \cite{SRIM:09} and fit the $k_B$ parameter to match  our {\small $\mathcal{L}_\textrm{eff}$}~ model to the data at 56~keV$_\textrm{r}$, finding $q_\textrm{el} = 0.65 $. Hitachi
\cite{Hitachi:05} used $q_\textrm{el} = 0.68$  to match his model and the data
at  60~keV$_\textrm{r}$.

\section{Discussion}
\label{sec:discussion}
The high energy points (56 and 66 keV$_\textrm{r}$) agree with previous {\small $\mathcal{L}_\textrm{eff}$}~
measurements. The {\small $\mathcal{L}_\textrm{eff}$}~ measurements from 20 to 46 keV$_\textrm{r}$~  suffer
from a low differential neutron-nuclear elastic scattering
cross-section compared to lower nuclear recoil energies
and thus have higher backgrounds
Therefore, this results in larger statistical errors for measurements in this energy range.
The detector was designed to
minimize multiple scattering background
for energies below 15 keV$_\textrm{r}$~ (see Figure \ref{fig:n_sim}). For
10~keV$_\textrm{r}$, the {\small $\mathcal{L}_\textrm{eff}$}~ value agrees with previous experiments. For
energies below 10 keV$_\textrm{r}$, our results are lower than the Chepel
\cite{Chepel:06} results and agree with the Aprile \cite{Aprile:08}
values within errors. However, our results suggest a decreasing {\small $\mathcal{L}_\textrm{eff}$}~
with decreasing energy and not a constant as suggested by
\cite{Sorensen:09}. Our results disagree with the {\small $\mathcal{L}_\textrm{eff}$}~ curves found
by comparing calibration data and Monte Carlo simulations (Figure \ref{fig:results_finalMC}) done by the XENON10 \cite{Sorensen:09} and
ZEPLIN-III \cite{Lebedenko:08} collaborations. The ionization yield (Figure \ref{fig:QEQ0}) measured in this work is in agreement with  previous measurements \cite{Aprile:06} and the XENON10 Monte Carlo analysis \cite{Sorensen:09}.

The theoretical {\small $\mathcal{L}_\textrm{eff}$}~ models by Lindhard \cite{Lindhard:63} and
Hitachi \cite{Hitachi:05} fail to explain our measurements. The
theoretical model presented in this paper, which includes the effect
of escape electrons, fits our measurements within errors.
This {\small $\mathcal{L}_\textrm{eff}$}~model is a simple one and several corrections can be done.
As pointed out in \cite{Hitachi:07}, for LXe the Lindhard model is a crude approximation below 15 keV$_\textrm{r}$,
and so the model could be improved below this energy. A more general expression for $q_{\textrm{esc}}$ could also be used that includes
different values of $\alpha$ for nuclear recoils and electron recoils  \cite{Dahl:09-phd}
as well as any energy dependence of  $\alpha$.

The {\small $\mathcal{L}_\textrm{eff}$}~ energy dependence measured in this work affects the dark matter limits set by LXe detectors. Figure \ref{fig:XE_limit_paper} shows the XENON10 result \cite{Angle:08} (top solid line)  found using {\small $\mathcal{L}_\textrm{eff}$}=0.19, as well as the projected spin-independent limits using {\small $\mathcal{L}_\textrm{eff}$}=0.19 (solid blue line) and the {\small $\mathcal{L}_\textrm{eff}$}~from this work (dotted line). The latter two curves are  90\% confidence limits based on Feldman-Cousins unified approach \cite{Feldman:98} for a LXe detector with a 30,000~kg~day exposure with no backgrounds in the 0.95 to 5.7 keVee energy window. This energy window corresponds to 5 to 30 keV$_\textrm{r}$~using {\small $\mathcal{L}_\textrm{eff}$}=0.19, and to 8.4 to 39.0 keV$_\textrm{r}$~using the measured {\small $\mathcal{L}_\textrm{eff}$}~ in this work. At a WIMP mass of 10 GeV/c$^2$, the WIMP nucleon cross-section limit  is more than an order of magnitude higher with the measured {\small $\mathcal{L}_\textrm{eff}$}, compared to the limit found assuming {\small $\mathcal{L}_\textrm{eff}$}=0.19. At 50 GeV/c$^2$ the WIMP nucleon cross-section limit is only 35\% higher and is 20\% higher above 100~GeV/c$^2$.

\begin{figure}[htbp]
	\centering
		\includegraphics[height=3in]{fig/XE_limit_paper_16.pdf}
	\caption{(Color online) Projected spin independent dark matter limits for a LXe detector with 30,000~kg~day exposure and 0.95 to 5.7 keVee energy window. The bottom solid line shows the limit with {\small $\mathcal{L}_\textrm{eff}$}=0.19 (5 to 30 keV$_\textrm{r}$~ window) while the dotted line shows the limit calculated with the measured {\small $\mathcal{L}_\textrm{eff}$}~(8.4 to 39.0 keV$_\textrm{r}$~ window).
 Also plotted are the  XENON10 result \cite{Angle:08} (top solid line) and the regions predicted by  \cite{Baltz:04:limit} (red shaded region) and \cite{Trotta:08} (green shaded region). Plot generated using \cite{dmplotter}.}
	\label{fig:XE_limit_paper}
\end{figure}

\section{Summary}
\label{sec:summary}
This work presents a new {\small $\mathcal{L}_\textrm{eff}$}~ measurement for energies between 4
and 66 keV$_\textrm{r}$. This measurement was done using a single phase ($S1$
signal only) and a dual phase detector ($S1$ and $S2$ signals) to
understand the detector's response at low energies. Each energy
measured was repeated with at least three different electric fields
finding no clear dependence of nuclear recoil scintillation  yield at low energies. We also present a
theoretical {\small $\mathcal{L}_\textrm{eff}$}~model including nuclear quenching, bi-excitonic
collisions and escape electrons that agrees with our results.
Our {\small $\mathcal{L}_\textrm{eff}$}~ results and model suggest a decreasing {\small $\mathcal{L}_\textrm{eff}$}~ with
decreasing energy. This result changes the  spin
independent limit as shown in Figure \ref{fig:XE_limit_paper}.
Although our {\small $\mathcal{L}_\textrm{eff}$}~result significantly changes the cross-section limit at low WIMP masses, the limit is only changed by 20\% for WIMP masses above 100 GeV/c$^2$.

In addition, we present the results for the nuclear recoil ionization yield
and calculated the fraction of  escape electrons
for nuclear recoil energies between 4 and 66 keV$_\textrm{r}$.

\begin{acknowledgments}
	The authors would like to thank  George Andrews and Kevin
Charbonneau for their assistance in running the neutron generator.
The authors would also like to thank the Yale University Biomedical
High Performance Computing Center where the simulations were
performed. We thank Aaron Manalaysay for useful comments on the manuscript.
This work was supported by National Science Foundation grant  \#PHY-0800526.
\end{acknowledgments}

\bibliographystyle{h-physrev3}

redpajama_set_name: RedPajamaArXiv


It was set to be 5GHz only, but it was also 802.11N only as well. I changed it to allow 802.11A compatibility and turned off wide channels.
The range is now improved. I'm typing this in a room that was out of range yesterday.
I understand that someone on the internet has compiled a considerable number of issues for iWork on iPad.
Workaround: export the completed slides to image files. Put them into an iPhoto album and have the iPad play that album as a slideshow. It's not as fancy, but it will play in a loop until you stop it. And if you make it the one album for locked mode, you can play it without leaving the iPad unlocked.
In playing with the iPad's Office products, I've started trying to my existing presentations and Pages files to it.
Solution: check that you included appropriate frameworks in your project and target.
I had this just now while building a new project and forgot to put the frameworks into the project.
I have a Samsung Blue-Ray player that my wife gave me for Christmas in 2009. Every since, my family has been asking (pestering) me to connect it to the internet so they can watch NetFlix downloads on it.
I connected it to my laptop with an ethernet cable and set it up as bridge the house WiFi, then connected it to the blue-ray player with the same ethernet cable. I checked the setup on the player for networking and voila! It was on the internet and we began the NetFlix setup.
I didn't have to buy hardware that might have only worked on Samsung's player.
I can attach the Airport to my stereo and send music through it.
If I lose the player for some reason, I can re-use the airport for other things.
A few days ago, I was helping upgrade a Mac's XCode environment from 3.1.4. After the upgrade, the first attempt to build and run a project resulted in strange errors. "Security Policy Violation" came back from the device along with problems with the entitlements.
After much poking and prodding, I noticed that the Base SDK for the project was set to "iPhone OS 2.0 (missing)". The base SDK for the project was no longer available in XCode after the 3.2.2 upgrade.
Resetting the BaseSDK to 3.0 solved the issues and the build and run was fine.
Need to Link to an iTunes property?


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"It seems like another one of these classic cases of money coming from industry with no strings attached — that's the official message. But it's a very different kind of story taking place," said Leigh Turner, an associate professor at the University of Minnesota's Center for Bioethics, who studies academic integrity and conflicts of interest.
In an introductory video, one of the Global Energy Balance Network's leaders said the media focuses on "eating too much, eating too much, eating too much — blaming fast food, blaming sugary drinks and so on." The video has since been taken down, and the group said the idea that it only focuses on physical activity is inaccurate.
The group wants to continue its work, he said.
Since 2010, Coke said it gave $550,000 to Hill that was unrelated to the group. A big part of that was research he and others were involved with, but the figure also covers travel expenses and fees for speaking engagements and other work. It does not include money from Coke's overseas divisions or industry groups such as the American Beverage Association.


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344.5 - 432. 4.73287 1766.888 -59.128 Dykyj, Seprakova, et al., 1957 Coefficents calculated by NIST from author's data.
Moving the mouse pointer over or near a point will display the coordinates of the point. The number of digits shown do not reflect the uncertainty of the value.
L Toggle log-log display if possible.
S Toggle semilog (log Y) display if possible.
K Move / hide legend (key). Repeated presses of this key will posiiton the legend in the following sequence: upper left, upper right, lower right, lower left, hidden.
Click in or tab to the plot area to enable keyboard commands.


I am going to apologize in advance, because I plan on gushing about Charleston for the next few posts. I bought this Phillip Lim skirt about a month ago and have been dying to find the right time (and weather) to wear it. One of my first nights at home coincided with the Preview Party for the Charleston Antique Show which provided the perfect opportunity to wear the skirt. I was skeptical on the Suno crop top at first, but I have already worn it twice and I find it so effortless. These Prada sandals are one of my best purchases ever and I only wish I had bought two pairs, because I wear them all the time. The skirt is classic and timeless and can be worn at basically any occasion, dressed with a variety of tops and shoes. I'm already thinking about the next outfit around this skirt.


text:
Q: Нельзя преобразовать тип real к integer с функцией синуса
Условие задачи: Определить количество тех членов последовательности
Ak=SIN(K`2+C), K=1,2,….,10, которые удовлетворяют условию 0≤AK≤1/2.

   var
      K : array [1..10] of real;
      C : real;
      SUM : integer;
      a : real;
    begin
      for var i := 1 to 10 do
      begin
        read(K[i]);
        read(C);
        a := Sin((power(K[i],2))+C);
        if a >= 0 and a <= 0.5 then
          SUM += 1
      end;
      writeln(SUM)
    end.

Не могу понять откуда берётся этот integer, который я нигде не объявляю. Что не так с этим кодом?

A: Ошибка происходит при попытке вычислить выражение if'а a >= 0 and a <= 0.5
Порядок действий слева направо:

*

*>=

*and

*<=
После первого действия получаем результат типа Boolean
Дальше идёт попытка вычислить and между булевым результатом и a.
В pascal оператор and имеет два разных действия:

*

*между двумя Boolean - логическое «И»

*между целочисленными типами - побитовое «И».

Так как a - не Boolean, то идет попытка применить побитовое «И». Boolean легко преобразуется в Integer, а вот при попытке преобразовать a к Integer получаем ошибку из заголовка.
Решение - явно задать порядок действий правильной расстановкой скобок: (a >= 0) and (a <= 0.5)

A: Нужно просто добавить скобки в условии
if (a >= 0) and (a <= 0.5) then

redpajama_set_name: RedPajamaStackExchange


text:
let us help you today 323.857.9500
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Los Angeles Racial Discrimination Attorney
It is illegal for a future employer to base hiring decisions on an applicant's racial background or ethnicity. An interviewer may not ask questions about an applicant's name and origin or whether the applicant is of a mixed race. It is similarly illegal for an employer to base employment decisions on an employee's race or ethnic background. This includes all related aspects of the job, such as work assignments, transfers, promotions, board appointments and particularly, terminations. Firing based on race is strictly prohibited by Title VII of the Civil Rights Act. If you feel you were a victim of racial or ethnic discrimination in the workplace, it is advisable to consult with an experienced Los Angeles racial discrimination attorney to discuss whether you may have a viable claim for compensation in the form of monetary damages. Grey Law vigorously defends victims of racial and ethnic discrimination. A complimentary consultation is available to review the circumstances of your racial discrimination situation. Our Los Angeles employment law attorney will carefully review your case and discuss available options. You may schedule your appointment by calling 1-800-GREY-LAW.
More About Racial-Ethnic Discrimination:
California's Fair Employment and Housing Act (FEHA) specifically prohibits discrimination in the workplace. The meaning of the words "ethnicity" and "race" extend to the individual's ancestry and background and include a multitude of situations and circumstances, including, but not limited to:
It is illegal to discriminate against an employee who has an interracial spouse or family
It is illegal to discriminate against an employee who does not speak the same language exclusively as the other employees
It is illegal to create an English-only policy when it is not relevant to the work
It is illegal to discriminate based on skin color, accent or language
It is illegal to discriminate based on personal preferences or prejudices of any kind
Racial and/or ethnic discrimination of any kind may be grounds for a legal claim. It is important to carefully review the circumstances of each situation in order to determine whether a viable claim exists.
Contact a Los Angeles Racial Discrimination Attorney for a Free Case Evaluation:
A Los Angeles racial discrimination lawyer from Grey Law will sit down with you and carefully listen to what you have to say in your free consultation. If a viable racial/ethnic discrimination case exists, your case will be taken on a contingency fee basis, which means that there will be no legal fees unless we attain a favorable resolution. Grey Law has been helping clients recover compensation for more than 25 years. Compensation may include lost wages, hiring or rehiring, damages for emotional pain and suffering, and in egregious cases, punitive damages. While the majority of cases are settled out of court, we will be prepared to fight for your rights in front of a judge and jury. To schedule your free consultation, call us at 1-800-GREY-LAW.

redpajama_set_name: RedPajamaCommonCrawl


Fun Things To Do In Tauranga And Mt. Maunganui You Shouldn't Miss!
Heading to the Bay of Plenty? In this case you should definitely not these fun things to do Tauranga and Mount Maunganui!
It had all looked so promising on the forecast. Friday morning the weekend looked all lovely and I my app told me that there were going to be 11 hours of sun on both Saturday and Sunday. So we decided on a last minute roadtrip down to Auckland's favourite holiday resort, Mount Maunganui.


text:
Tag Archives: Mahatma Gandhi
Lessons from Gandhi
My wife, being a prolific reader of novels, is always going with me to return books to the local library. At the very front of libraries is a section for recommended new books. While there, I was pleased to find a brand new book Gandhi Before India. It was news to me that Gandhi was excommunicated by his own Bania caste from daring to go to England to become a lawyer: "For his transgression, the boy would be treated as an outcaste; anyone who spoke to him or went to see him off would be fined."[1] Gandhi's family sacrificed greatly to send him to England, even pawning the family jewels. While in England, Gandhi for the first time read the Bible, finding the New Testament compelling, especially the Sermon on the Mount. [2] As Gandhi commented, it 'went straight to my heart'. The lines about offering one's cloak to the man who had taken away one's coat touched him greatly.[3] Gandhi demonstrated that the Sermon on the Mount will radically change one's life and one's society if put into practice.
After completing his law degree in England, Gandhi returned to India for a short while before moving to South Africa. While there are numerous books on Gandhi, many skip over Gandhi's foundational twenty-one years in South Africa. Even the excellent Gandhi movie by Richard Attenborough doesn't do justice to the prolonged complexity to Gandhi's time in South Africa. Dr. E Stanley Jones commented that South Africa provided the rehearsal for the real drama of India: "He might have floundered had he tried India straight off."[4] Sadly in South Africa when Gandhi was most interested in the Gospel, he encountered the greatest restrictions: "To allow Gandhi to sit along white worshippers was impossible. The vicar's wife, out of solidarity and sympathy, offered to sit with him in the vestibule, from where they heard the service."[5] One of the people who had the greatest impact on Gandhi was Leo Tolstoy, especially his book The Kingdom of God is within You: "he was 'overwhelmed by the independent thinking, profound morality, and the truthfulness of this book."[6] Gandhi purchased and gave out even to his jailers countless copies of Tolstoy's ground-breaking book on peacemaking in the Sermon on the Mount.[7]
Upon returning to India, Gandhi was initially rejected by other Indians who feared that they might become ritually polluted by even offering a cup of water to someone of the wrong caste.[8] When Gandhi successfully stood up for their rights, he became hailed as a hero and liberator. Gandhi campaigned nonviolently for the independence of India for numerous decades, spending 2,089 days in Indian jails (almost six years).[9]
Dr. E Stanley Jones described Gandhi as the architect of the new India.[10] In many ways, Gandhi was like an Abraham Lincoln bringing freedom to hundreds of millions of his fellow citizens. Louis Fischer compared Gandhi to David standing up to the Goliath of racial discrimination.[11] Gandhi went from being an initial supporter of caste discrimination to being a campaigner against its divisiveness. Jones commented:
…in his life, (Gandhi) breaks all the rules of caste, transcends them, adopts an outcaste as his daughter, and in the end does more to break down the system of caste than any other man, living or dead."[12]
Jones held that "in Gandhi the word of freedom became flesh. When he spoke, freedom spoke. Gandhi was India."[13] Most people believe in democratic freedom. Not many are willing to sacrifice over many decades to obtain such goals. Before Gandhi, it was mostly the Indian intelligentsia campaigning for democracy. Because Gandhi humbled himself and unselfishly served the poor and untouchables, both rich and poor awoke to the vision of an independent India.[14] Gandhi made room for all regardless of race, religion and wealth. Albert Einstein said regarding Gandhi: "Generations to come will scarce believe that such a one as this ever in flesh and blood walked upon this earth."[15] In reading Jones' book Gandhi: Portrayal of a Friend, Martin Luther King Jr. was inspired to launch the nonviolent Civil Rights Movement.[16]
Jones described the complexity of Gandhi's personality as like Mount Everest:
Gandhi was simple and yet very complex amid that simplicity. You thought that you knew him and then you didn't. It was intriguing. There was always something there that eluded your grasp, that baffled you. And yet out of that many-sidedness which amounted to complexity, there arose simplicity, a unified character, simple and compelling.[17]
In an India full of racial, religious and economic division, Gandhi brought people together, giving them a vision for an independent democratic India. Gandhi , whose favorite hymn was 'When I survey the Wondrous Cross', chose the costly way of the cross, of sacrificial love even for his enemies.[18] On the wall of his mud hut was a black and white picture of Jesus Christ under which was written 'He is our peace'.[19] Gandhi was a peace-maker who chose to forgive those who despised him and rejected him. Every day he would read Jesus' Sermon on the Mount, motivating Gandhi to peacefully love his adversaries. Jones, who had been a friend of Gandhi in India for many years, said once to him: 'You understand the principles. Do you know the person?' Gandhi was very drawn to the person of Jesus Christ. My prayer for those reading this article is that we may embrace both the principles and person of Jesus' Sermon on the Mount.
[1] Ramachanadra Guha, Gandhi Before India (Random House Canada, Toronto, 2014), p. 34-35.
[2] Guha, p. 45.
[4] E Stanley Jones, Gandhi: Portrait of a Friend (Abingdon, Nashville, 1948), p. 18.
[7] Guha, p.308: "Before he left Volksrust Prison (in 1908), he presented a kindly warder with an inscribed copy of Tolstoy's The Kingdom of God is within You."
[8] Guha, p. 225 "Raj Kumar Shukla took Gandhi to Champaran and Patna the capital of Bihar. …since no one knew their caste, even the servants shunned them. The maids refused to draw from the garden well when Gandhi used it, for fear that even a drop of water from Gandhi's bucket might pollute them."
[9] Guha, p. P.160.
[10] E Stanley Jones, Gandhi: Portrait of a Friend (Abingdon, Nashville, 1948), p. 1.
[11] Louis Fischer, Gandhi: his life & message for the world (Signet Classics, New York, NY, 1954, 1982), p. 20.
[12] Jones, p. 6; Arthur Herman, Gandhi and Churchill (Bantam Dell, New York, NY, 2008), p. 120-121 The early Gandhi in 1921 supported caste discrimination: "Prohibition against intermarriage and interdining (between Hindu castes) is essential for the rapid evolution of the soul." By 1932, he rejected such prohibitions. By 1946, he only permitted inter caste weddings on his premise.
[13] Jones, p. 32.
[14] Jones, p. 22 "…it was Gandhi who aroused (the rural people), made them shed their fears, and made them conscious of their destiny. Before the advent of Gandhi, the nationalist movement was among the intellectuals."
[15] The Words of Gandhi, selected by Richard Attenborough (Newmarket Press, New York, NY, 1982), p.9.
[16] http://www.estanleyjonesfoundation.com/about-esj/esj-biography King: "…it was his (Jones') book that triggered my use of Gandi's method of nonviolence as a weapon for my own people's freedom in the United States." (accessed May 4th 2015)
[17] Jones, p. 5.
[18] Guha, p. 582 "(At the end of his final fast) the girls sang his favorite hymn When I survey the Wondrous Cross."; Jones, p. 39, p. 141.
[19] Fischer, p. 141.
Categories: Uncategorized | Tags: Abraham Lincoln, British Empire, Caste, cross, David, Dr. E Stanley Jones, England, Gandhi, Goliath, Gospel, India, Jesus Christ, Lawyer, Leo Tolstoy, Mahatma Gandhi, New Testament, Peacemaker, racism, Richard Attenborough, Sermon on the Mount, South Africa, untouchable | Permalink.
Say No to the Herd
Every summer the Hird family goes away on a BC Christian Ashram retreat to Sumas Mountain. The United Christian Ashram movement was founded in 1930 by Dr. E. Stanley Jones in India. As a close friend of Mahatma Gandhi, Jones wrote twenty-eight books that sold millions, including Christ of the Indian Road and Abundant Living. As the most widely read spiritual author during his lifetime, Jones left a remarkable impact that is rapidly increasing in our social media world. Jones' short aphorisms are very quotable, being often reposted on Facebook, Twitter, Google+, LinkedIn, and Pinterest.
For the last year, I have been rereading Jones' book The Way to Power and Poise. Jones memorably warns us against the herd: "If we are herd-centered people, then we are insecure, for the herd is fickle and may quickly change." Teenagers, when facing peer pressure, are often tempted to be herd-centered. When we give up self to the herd, we lose identity, focus and creativity. The desire to be popular and to fit in can be very deadly. It takes courage to be ourselves. Jones taught that if we are dominated by the herd, we are doomed by the herd – doomed to a life of up and downness.
There are four possible attitudes, said Jones, to the herd urge. We can 1) withdraw from the herd 2) defy the herd 3) succumb to the herd or 4) surrender the herd to God and then live within it.
The problem with the first attitude of withdrawal is that we are left in isolation and eccentricity. All forms of separation, segregation or apartheid backfire upon themselves. Emotional cut-off solves nothing. We are called to be in the herd but not of the herd.
The second attitude of defying the herd leaves us on the defensive. As Jones put it, you cannot live constantly objecting without becoming objectionable. Defensiveness is negative and self-defeating. Healthy people do not define themselves by what they are opposed to.
The third attitude of succumbing to the herd, said Jones, robs you of your voice: "you are an echo; you don't act; you only react; you are not a person but a thing." Mindless conforming is ultimately deforming. Giving up self to the herd leaves us flat and empty. Mob mentality, as with the 2011 Vancouver Canuck riot, is rooted in the herd mentality. Many young people going to that Canuck game had no idea how destructive they would become.
The fourth attitude, said Jones, is to break the dominance of the herd by surrendering the herd to God. Then we cease to be people-pleasers and become God-pleasers instead. We become people who have the courage to speak, to risk, to be different. Bullies and dictators no longer control us. When God is God instead of the herd, then we receive a peace that passes all understanding. We become non-anxious catalysts that change our families, workplaces and herds.
Only when we let go and let God can the herd become healthy. The herd will drain you of life and energy, if you let it. The herd is never satisfied. You can never do enough to please the herd. Jesus gives you the ability to transform the herd into a thing of beauty. Say no to the herd, and yes to life.
To learn more about the BC Christian Ashram retreat, click on the following link.
-Click to check out on Amazon our newest marriage book For Better For Worse: discovering the keys to a lasting relationship. You can even read the first two chapters for free to see if the book speaks to you.
Categories: Uncategorized | Tags: abundant living, Christ of The Indian Road, Christian Ashram, E Stanley Jones, Facebook, Google, Herd, Hird, LinkedIn, Mahatma Gandhi, Pinterest, Sumas Mountain, The Way to Power and Poise, Twitter | Permalink.


text:
"Форека" ООД (Foreca Oy) е частна компания в Еспоо, Финландия, занимаваща се с метеорологични прогнози.

Компанията е най-голямата по рода си в скандинавските страни: Дания, Исландия, Норвегия, Финландия, Швеция и свързаните с тях зависими територии Оландски острови, Фарьорски острови, Гренландия. Седалището на фирмата е в град Еспоо, има офиси още в столицата Хелзинки, както и в Стокхолм и Москва.

Създадена е през 1996 г. под името "Метеорологична служба Финландия" (Weather Service Finland) от местния метеоролог Пирко Сарикиви (Pirkko Saarikivi) и 4 специалисти. През януари 2001 г. името ѝ е променено на "Форека" (от английското forecast – прогноза) с перспектива за разширяване на международно ниво.

През 2004 г. компанията подписва договор с Microsoft за предоставяне на метеорологично съдържание за техните международни MSN страници. Чрез тези страници Foreca предоставя прогнози за времето, преведени на 25 езика за 194 държави и 8500 града. Това е компанията, която дава информация за времето за приложението на Windows 7, както и за MSN Weather и Cortana.

Компанията има безплатно приложение за прогнози на времето за смартфон устройства, наречено ForecaWeather Free. Приложението дава информация за моментна прогноза на времето,10-дневна прогноза за времето, както и анимации, показващи облачността, дъждовете и топлинна карта навсякъде по света. Разработено е за Android, iOS, s60.

Източници

Външни препратки
 Foreca.mobi – мобилен уебсайт
 Corporate.foreca.com - уебсайт за бизнес клиенти
 Foreca.fi – официален уебсайт на финландски език
 Foreca.com  – официален уебсайт на английски език
 MSN Weather  – метеорологичен сайт, използващ данните от Foreca за прогнози за времето

Компании в Еспоо
Наука във Финландия
География на Финландия
Метеорология

redpajama_set_name: RedPajamaWikipedia


Cairo's dusty and endless cityscape.
Constructed some 4,500 years ago, The Giza Pyramids were built under Pharaoh Khufu's instruction as a tomb for the Egyptian pharaohs' bodies in preparation for their afterlife as gods. The Great Pyramid is the largest in Giza and contains an estimated 2,3 million stone blocks. The Sphinx limestone monument, a cross between a lion and a pharaoh, was seen as a guard for the tomb complex.
Khan El-Khalili is Cairo's most famous 'souk'. Dating back to 1382 and located in Cairo's old Islamic district. Unlike a lot of the other souks I've visited in other countries (e.g. Morocco or UAE), I've never visited a souk on such a large scale and as energetic as this one. And just like all souks which gradually develop into a tourist destination, be prepared for the almost inevitable, incessant harassment from overly-keen shopkeepers. You can find souvenirs, spices, perfumes, jewellery, traditional lamps, textiles and clothing etc here.
Heliopolis is one of the most ancient cities in Egypt, with beautifully crumbling buildings and an abundance of cafes and shops. The neglected, soon-to-be-demolished tram track also brings nostalgic vibes to this part of town. The El-Korba district is probably the main highlight of the Heliopolis neighbourhood. Founded early last century by a Belgian baron, the architecture combines both Islamic and Art-Deco architectural styles - a definite must-go for anyone interested in architecture! If you plan to visit, I would spend a few hours walking around El Korba's marketplaces and shops.
Considered as one of the more rural parts of Cairo, the Zaton neighbourhood can be found a stone's throw away from Heliopolis. Visiting this part of town definitely gave me a better perspective of local life in smaller communities in Cairo, although it's also not the safest place to visit. It was difficult to take photos in this area because the people living in Zaton were adverse to having their picture taken, believing in superstition about how the camera can "take away someone's soul". I definitely felt like an unwelcomed guest as I walked through this conservative part of town. At the same time, I kind of understood that I was intruding their privacy by stepping into a conservative and exclusive bubble where not many locals, let alone foreigners, usually tread on.
Locals gathering around the Zaton neighbourhood bakery.
Al-Azhar is one of the most unreal city parks I've ever seen, like from a computer game. This park with its beautifully manicured grass and world-class landscaping is situated on slightly higher ground in the middle of the city which grants its visitors an epic bird's eye view of the endless Cairo cityscape, plus the dramatic, towering grand Mosque of Muhammad Ali in the distance.
In a hectic and chaotic city with unceasing traffic and chatter such as Cairo, Al-Azhar is seriously a much needed space for its locals to find respite and solace.
The entrance to Al-Azhar Park delineates a polarising landscape between the park and Cairo city.
View from the other side of Al-Azhar Park.
For all your shopping needs and more, Cairo Festival City Mall is an excessively HUGE shopping establishment where you can probably find anything you want. The mall is complete with a huge water fountain display in its outdoor courtyard, and also has an outdoor bazaar selling handmade goods.
Naguib Mahfouz Cafe was named after an Egyptian writer who won the 1988 Nobel Prize for Literature. The cafe is one of the most memorable dining places I visited in Egypt - a rustic hidden gem behind a set of closed doors in one of the many marketplaces in the Khan Al-Khalili Bazaar. The local crowd that gathers here for food, drink and live music are also from a noticeable wealthier class. The interiors are a modern-take on Arabic design, and the waiters here are all clad in traditional uniforms and wear a red, tassled, felt cap (also known as 'Fez').
We came here for drinks and shisha for a quick break away from the hustle and bustle from the Khan Al-Khalili market. I also had a delicious traditional Egyptian hot milky drink (with chopped almonds, raisins and date syrup was it?!) but unfortunately I can't remember what it was called. The sudden transition from the casual market streets into a clean and relatively posh venue, the intoxication from the shisha and the traditional Egyptian music coming from the live band made us feel like we were being transported into a whole other universe!
The waiters at Naguib Mahfouz Cafe are all clad in traditional uniforms and wear a red, tassled, felt cap (also known as 'Fez').
I was taken here by Adam's cousin who swears by Andreas serving the best oven-roasted chicken in Egypt! First of all, we liked the casual and modern alfresco dining area. We ordered a few whole chickens to share, along with little dishes of cold mezze, including my favourite Warak Inab (stuffed grape vine leaves). For me, the highlight was the homemade oven-baked bread baked by a few middle-aged ladies who literally roll the dough from scratch, and watch over the baking process of the bread in the oven.
A traditional Egyptian dish, Koshari is made of lentils, rice, macaroni, chickpeas, tomato sauce, onions, garlic, oil and vinegar.
Abou Tarek is the most famous restaurant serving these little boxes of Koshari, where you will see both locals and tourists eating here.
Alain Le Notre serves Arabic/ Mediterranean cuisine, and this was definitely one of the more expensive (but still affordable if you compare it to London prices) meals that we had in Cairo. I was intially quite disappointed when I heard that it wasn't 'Mango Season' when I visited Egypt. Egyptian Mangoes are said to be the pride and joy of the country as far as fruit is concerned. Bigger restaurants, though, are capable of freezing their fruit so you can enjoy juices whatever the season. We went for the fresh Guava and Mango juice - absolutely divine! We also ordered Adam's favourite Molokhia - a thick and watery leafy green soup which is unique to Egyptian cuisine.
Faharat is most well known for its famous stuffed baby pigeon, Although I didn't order it, most of the people dining at Farahat (99.9% locals) were ordering it - so it must be good?? Other than that, this restaurant serves traditional Egyptian cuisine - mostly spiced meats and sausages and freshly stone baked Mahlab bread and Flatbreads, accompanied by delicious cold mezze like hummus and roasted eggplant matbucha. The menu is entirely in Arabic (that's how authentic it is), so unless you can read and speak Arabic, you might need help from a stranger or a local friend.


text:
Q: Using str_replace to make hundreds of spelling corrections I'm looking for a more efficient way of replacing lots of strings. I'm essentially running a manual spell check across my entire df, where incorrectly spelled responses / typos are corrected:
df <- df %>%
            mutate_all(funs(str_replace(., "^anker$", "anchor"))) %>%
            mutate_all(funs(str_replace(., "^baloon$", "balloon"))) %>%
            mutate_all(funs(str_replace(., "^celeary$", "celery"))) %>%
            mutate_all(funs(str_replace(., "^dear$", "deer")))

This works great, and I've done the tedious job of finding everything I want to change, but having the same line of code copy and pasted like this (for hundreds of corrections) isn't pretty. Is there a way I can feed a df into str_replace to get a similar results? I was thinking something like this:
"Spell_check_df" that looks like this:

   responses     correction
---------------------------
1. ^anker$       anchor
2. ^baloon$      balloon
3. ^celeary$     celery
4. ^dear$        deer

df <- df %>%
            mutate_all(funs(str_replace(Spell_check_df, responses, correction)))

Any help would be appreciated - I just can't seem to get it working. Obviously I want the responses and corrections to be tied together.

A: spell_check_vec <- Spell_check_df$correction
names(spell_check_vec) <- Spell_check_df$responses
str_replace_all(.,spell_check_vec)


I received this book as an ARC through Net Galley in exchange for an honest review. This was a nice short story about love, and what drives people together, and what it takes to make a relationship work. I liked the characters, and I like what lead to their break up was neither outside forces driving them apart, or a silly big misunderstanding. I liked that their break up felt like it was rooted in the problems in their relationship, and the fears and pride of both men. I think the time skip really worked well in this story. It allowed me to feel the time, and the changes the men had undergone while they apart without having to give a minute by minute recounting of all seven years. I found the ending to be well done, and I liked that it felt happy without feeling unrealistic, or too sappy. It worked for the characters, and I appreciated that. Overall a nice love story for a cold winter day.


I try not to snipe at other sites. It's boring to most readers and seems petty. Today, I can't resist.
Secret Squirrel over at the Montana Cowgirl Blog disparages Bernie Sanders' supporters, likening the Senator to Ralph Nader in the 2008 presidential election.
What was the Squirrel thinking? Most folks who follow political blogs are activists. And most activists in the Democratic Party are Bernie supporters. There are even some out there who think Sanders is too moderate, at least on foreign policy issues. So a post promoting Hillary Clinton is bound to draw some ire. It did. Right now, it looks like about 95 percent of the comments are pro-Bernie.
Check it out. On the Montana Cowgirl plus side, though, I'll bet the post has generated a lot of traffic.
Think how far Bernie would be up in the polls right now if he'd been a little more pro-active in the debate instead of slobbering all over her.
"Slobbering all over her?" He made one comment about the American public being sick of Hillary's email controversy, which I happen to agree with. I suppose you'd be happier, Swede, if the Democratic candidates took a page out of the Republican debate handbook and stabbed each other in the back.
I thought republicans still abided by Reagan's Eleventh Amendment?
Since when did that change?
It changed when the party became ruled by Rhinos.
Such a short memory. Let me take you back to Nov. of '07.
MT Cowgirl steps in it again for its puzzling silence on Denise Juneau.
Interesting observation, HighPoint. Maybe just an oversight or the fact that other blogs have already posted on it. I will keep an eye on that site, though.


text:
In Anarchy Online, The Advisors of Rubi-Ka (or ARK for short) are often the first point of contact for players who need customer service. ARK is made up of a special group of individuals who freely volunteer their time and energy to help other players. It is the Advisors number one responsibility to further enhance the overall game experience of every player by serving as the first line of customer service for Funcom.
More information about the ARK program and how to join can be found at the ARK homepage
1 The Departments
1.1 Operations
1.2 Events
1.3 Community Relations
1.4 Personnel
1.5 Bug Hunters
1.6 Exploits Team
2 Origin - The N.O.A.H. Project
The Departments[edit]
ARK is divided into several departments that allow members to concentrate on specific tasks. However unlike many other volunteer programs, all Advisors are able to assist in most activities run by departments they are not part of. E.g. All Advisors can be part of events run by the events department.
Operations[edit]
Advisors in Operations spend the majority of their time answering petitions from players; anything from answering common game-play elements to fixing players stuck in the geometry. Operations Advisors can also spend their time running tours through the world for both new and experienced players. Greeters are a valuable group of volunteers who help welcome new players to Anarchy Online and make their start in this new world as painless as possible.
Events[edit]
The Events department is responsible for writing, producing and starring in small, medium, and large events that occur in various locations on both dimensions, and across all timezones. The Events department also assists the Funcom's team in running official events that affect the storyline of Anarchy Online. Any Advisor is eligible to participate in an event being run by this team, subject to training and certain limits on numbers. Events are also responsible for the Blue named NPC characters on Rubi-Ka, characters who will be in-character at any given time.
Community Relations[edit]
The ARK Community Relations department serves as a focused bridge of communication and interaction between AO players and ARK. CR assists the Funcom community team in functions such as looking out for bulletin board posts that need to be moderated or flagged to various people or teams in Funcom and ARK. CR communicates to fansites, etc. regarding ARK, and helps to connect players to proper Funcom and ARK contact points when unsure who to contact. CR also develops and manages the the ARK website.
Like any large organization ARK needs a personnel team, responsible for morale and staffing. The Personnel department keeps ARK running. They also conduct player customer service satisfaction surveys. Built within the Personnel department, the ARK Academy is a big team responsible for induction and training of ARK.
Bug Hunters[edit]
The Bug Hunters spend alot of time on the test servers, helping the Funcom Development and QA team check new patches and features for bugs, as well as helping to check balance issues. The Bug Hunters are most often found on the test server.
Exploits Team[edit]
The Exploit Team manages all reported and confirmed exploits. The department works primarily on the test servers to investigate exploit cases without disrupting live play. On the live servers, the Exploit Team monitors possible exploit situations. When necessary, department members step in to block the use of potentially exploitable bugs. All Exploit Team members are firmly set on the single goal of protecting fair game play through the elimination of exploits, and the re-education of those few players who take advantage of these bugs.
Origin - The N.O.A.H. Project[edit]
As the year 29473 AD drew to a close, the ICC found itself under mounting pressure. The ICC, the regulatory council for all mega corporations and hyper corporations across the known galaxies, was under increasing criticism regarding their control over the growing number of corporations. The general public opinion was that the ICC was losing its grip on a few of the larger and more powerful hyper corporations and false rumors of bribery were beginning to circulate.
In an effort to mend public relations, denounce all charges of bribery and to strengthen its image in the public eye, the ICC began to undertake the task of constructing a department to aid the best interests of the public. The Advisors, as they were to be known, were designed to be a department consisting of people that would deal directly with the general public, assisting them with their problems, questions and concerns.
It was decided that in order to aid the public in any foreseeable way, Advisors would have to be nano-enhanced to a level superior to that of current standards. An expensive, and as of then untested, process was put into place by the ICC that enabled notum to be bonded directly with the body cells of the Advisor, allowing them to control nano technology in a way not yet seen before by science. There were hints of reports coming out of the ICC technology division detailing that not all Advisors survived the nano bonding process. According to some insiders, only the "worthy" were able to survive the harsh process.
As the ICC continued to build the Advisor department, they maintained their experimentation with nano-enhancement technology, known as Neo-Technology. Advancements were made month after month, with each improvement requiring more credits for funding. The program needed to move into the next phase of operation. The ICC planned to spread the Advisors across the galaxy but the foundation for the program needed to be constructed. This phase would move the program closer to the source of the mineral Notum, so the Advisors could have easy access to the one vital element of the program while they would grow in numbers and develop an administrative structure of a non-profit organization. It was unanimously agreed that moving to Rubi-Ka was the most logical choice for the benefit of the Advisors.
When they arrived, the nano-enhanced Advisors experienced a strange reaction to the Notum dusty planet. Confused by this new environment and psychological changes, they stayed hidden from the public view for a long time, watching and learning about the lands and people of Rubi-Ka. These changes enhanced the Advisors to a new level only previously discussed in theory - they were developing into Genetic Manipulators. On Rubi-Ka, the Genetic Manipulators had seen the conflict between Omni-Tek and a number of clans, referred to by many as the Rebels. Observing the pain and suffering of both planet and it's inhabitants, the Genetic Manipulators realized they had been presented with a chance to use the gifts and ideals they were born and bred to use.
The newly formed Genetic Manipulators learned they could accomplish new abilities and soon they were confident enough to invite a selected group of Rubi-Ka citizens to begin their training as Advisors. The Genetic Manipulators had observed these citizens for quite some time and saw in them the knowledge and true compassion for all of the inhabitants of Rubi-Ka. The Genetic Manipulators enhanced their bodies to new levels using their knowledge of Neo-Technology. This first group of Advisors would be known as the Founders.
The Founders developed the infrastructure to swell their numbers so they could train more candidates, as they were called, and enhance them into Advisors. More Advisors meant more help for the citizens of Rubi-Ka.
When they were ready, the Advisors and GM's revealed themselves to the people of Rubi-Ka, knowing full well that the only way to help these citizens was to provide humanitarian aid to all. The Advisors' official and moral stance of the conflict would be neutral so they could assist all citizens that came to them, regardless of their affiliations or politics.
Travelling from city to town, from landmark to outpost, and from desert to sea, the Advisors spread the word of their intentions and pure concern for the inhabitants of Rubi-Ka. Citizens that had been aided by the Advisors began to donate credits or items as a token of their thanks. Rubi-Ka, being a planet leased by a hyper corporation and a home to many wealthy citizens, had quite a lot to offer the Advisors, and they soon found themselves with suitable funds to purchase and maintain their own Neo-Technology infrastructure and to build offices in major cities so they could be available to all in need.
Today, the Advisors wander the plains, mountains, deserts and forests of Rubi-Ka, conversing with its inhabitants, assisting the many and befriending all. They keep an impartial attitude, knowing that interfering in the conflict would most definitely cause more harm than good. Reporting to the ICC and recruiting neutral citizens, the Advisors maintain their presence and ideals upon Rubi-Ka, preserving life and aiding all that are blessed with it. It is known in the nano-enhanced heart of all its members, that they truly are Advisors of Rubi-Ka.
Retrieved from "http://wiki.aodb.us/index.php?title=ARK&oldid=15206"


This work is an introduction to the Summum Philosophy, a philosophy based on the principles of Creation that underlie all phenomena and address all issues of existence, sexuality, and death.
SUMMUM: Sealed Except to the Open Mind is an introduction to the Summum Philosophy, a philosophy based on the principles of Creation that underlie all phenomena and address all issues of existence, sexuality, and death. This book examines the cause of creation, seven basic fundamental principles, and humanity's place in the matrix of creation's formulations. It is truly a "must read" for anyone searching for a genuine understanding of Creation.


The following series of video slides show what do hemorrhoids look like. I must point out that the videos are VERY GRAPHIC and VERY VULGAR for sensitive viewers, and maybe should not be seen by such viewers.
N.B. Definitely not suitable for under age viewers, and sensitive viewers must take caution before looking at these videos.
Alternatively If you need some cure for your hemorrhoids then just read the E-Book on curing hemorrhoids Permanently.
This first video shows what some external hemorrhoids look like followed by what internal hemorrhoids look like.
This second video shows different thrombosed external hemorrhoids. Starting from a less severe case proceeding with more severe cases. There is a vivid blood scene in this video, and again I repeat that sensitive viewers should be warned and take note that this is VERY GRAPHIC AND DISTURBING!!!
TIP: This video is best watched if you push full screen button.
Something to note is although the first thrombosed external hemorrhoid is rather large in size, it is still at in the first stage of hemorrhoids, as it has not started to turn blueish in color.
The third video is the whole process of prolapsed hemorrhoids.
The fourth video is very severe cases of prolapsed hemorrhoids.
If you are still not sure what type of hemorrhoids you are struggling with, or need some specific questions answered with your own personal case of hemorrhoids.
Just fill in your details below and I will get back to you as soon as humanely possible. I do understand the urgency that you may have, but I am not always at my computer. However I do promise to get back to you a.s.a.p.
N.B. Under the Privacy Act, I promise that I will never pass on your details to any third party, for whatever reason at all. Therefore your details are safe with me.


Is your holiday calendar filling up? The busiest season of the year is upon us and I'm excited to partner with francesca's to share some ideas to help make the holiday craziness a little bit easier on you!
Let's start with the parties (my favorite part)! I can't help but want to treat myself to a few new outfit updates for all the activities, and francesca's has a great selection for head to toe holiday outfitting. I love this ruffle wrap dress – it's classic but still flirty and fun!
And I love the blue color of this dress paired with these light grey drop earrings. This outfit can be dressed up or down, but since I'm on the shorter side I tend to go for a little more height for a party. These classic metallic heels are feminine and versatile.
While browsing francesca's new arrivals I stumbled up this adorable "He See's You When You're Sneaking" cookie jar. My kids are SO excited about this.
And you guys… this is so funny that I have to share. While taking this picture Gray says "I've been singing the song wrong all these years. I thought it was really creepy that Santa saw you sleeping." Um…. ha!
I found so many cozy and fashionable gift ideas on francesca's site, too! A lot of cute and easy fitting ponchos and wraps for easy gifting right in their Holiday Gift Guide.
Be sure to scroll through below for more easy gifts and holiday outfits! Check out francesca's Holiday Gift Guide right here, and don't forget about their stores – we have on right here on King St in Charleston!
Photography by Gray Benko. Sponsored by francesca's and ShopStyle.


text:
Salon Palloilijat (abbreviated SalPa) is a sports club from Salo in Finland.  The club is popularly known as  The Swans.  SalPa was formed in 1956 and their home ground is at the Salon Urheilupuisto.  The men's football first team currently plays in the Kakkonen (Second Division).  The Chairman of SalPa is Toni Tammi.

The club currently has sections covering football, floorball, figure skating and basketball.

Background

Salon Palloilijat was established in 1956 and the club's first taste of success was in 1960 when the gained promotion to the Suomisarjaa (Finland League) which at that time was the second tier of Finnish football.  Their success at this level was short-lived but just over forty years later in 2001 they played one season in the Ykkönen (First Division) which is the current second tier.

SalPa have had four periods covering 25 seasons in the Kakkonen (Second Division), the third tier of Finnish football from 1978 to 1979, 1982–90, 1996–2000 and 2002 to the current day.

The club's highest attendance is 2,984 spectators (SalPa-Futistähdet 21.6.1999).  The largest attendance for a league match is 835 spectators (SalPa-AC Vantaa, 2001, Ykkönen – First Division).

SalPa have historically invested heavily in youth activities and continues to provide a thriving junior section.

Season to season

Club Structure

SalPa currently has 1 men's team, 1 ladies teams, 7 boys teams and 7 girls team.  The club organises various activities for its young players including skill and ability schools, tournaments and futsal.

References and sources
Official Website
First Team Website
Salon Palloilijat Juniorit Website
Finnish Wikipedia
Suomen Cup
 Salon Palloilijat Facebook

Footnotes

Football clubs in Finland
Salo, Finland
1956 establishments in Finland