Rachel MacDonald added observations.tex  almost 9 years ago

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\section{Observations\label{sect:obs}}  \subsection{X-ray Observations}\label{sect:obs-xray}  We observed \thistarget{} using the ACIS detector on board the \textit{Chandra X-ray Observatory} [\dataset [ADS/Sa.CXO#obs/14656] {ObsId 14656}] on 2013 December 9, starting at 00:52 UT, for $\sim$30 ks. Standard level-2 data products were used, and were processed and calibrated with the most current version of the CIAO software (4.7, CALDB 4.6.5).  Since \thistarget{} is known to vary over time, we wanted to determine whether this most recent X-ray observation differed significantly from previous ones. We therefore downloaded the two previous observations of this source from the Chandra Data Archive: \dataset [ADS/Sa.CXO#obs/00095] {ObsId 95} (2000 February 29), and \dataset [ADS/Sa.CXO#obs/05479] {ObsId 5479} (2005 August 20). These older observations were reprocessed using the same calibration information, software versions, tasks, and parameters as our most recent observation.  %Table \ref{table:xraycounts} gives the dates of the Chandra observations analyzed here, as well as the length of each exposure, the total counts for the source and the background, and the count rates for each.   The high energy particle background is known to increase rapidly on the ACIS detectors below 0.3 keV and above 8 keV. We therefore restricted most analysis to the energy range $0.3 - 8$ keV to minimize this background.   Background flares were removed from our observations by examining all data within the energy range $0.3 - 10$ keV, and removing time periods with count rates more than one sigma away from the mean. In this manner 0.25 ks were removed from ObsID 14656, leaving 29.4 ks for our analysis.  %To further reduce potential problems due to high backgrounds, we examined our data and removed time periods with count rates more than one sigma away from the mean. For ObsID 14656 this removed 0.25 ks and left 29.4 ks for analysis.   %The nominal energy range for the ACIS detectors is $0.1 - 12$ keV, however the high energy particle background increases rapidly below 0.3 keV and above 8 keV. As our source is quite faint, we restricted our analysis to the range 0.3 - 10.0 keV in order to minimize this background.   %In order to determine whether there were background flares which might interfere with our investigations, the \texttt{wavdetect} algorithm was used to detect point sources on the S3 chip; these sources were subtracted, and the remaining source-free background was examined for variability and flaring with the \texttt{deflare} task and the \texttt{lc\_sigma\_clip} routine. Based on this examination, only periods of time which had background count rates between 0.7 and 1.0 ct s$^{-1}$ were retained. In this manner 0.25 ks were excluded and 29.4 ks were kept for analysis.  Total counts and count rates for \thistarget{} were calculated using a circular aperture with radius 10 pixels. Background counts and rate were measured in an annulus centered on \thistarget{} with inner radius 11 pix and outer radius 20 pix. The source had 434 total counts, 0.0148 ct s$^{-1}$, in the aperture during our observation. For comparison, these values are shown in Table \ref{table:xraycounts} along with the total source counts and count rates for the two previous \thistarget{} observations (calculated using the same apertures given above).  \begin{deluxetable}{cccccc}  \tablewidth{0pt}  \tablecaption{\textit{Chandra} Observations of \thistarget{} \label{table:xraycounts}}  \tablehead{%\colhead{} & \colhead{} & \colhead{Actual} & \colhead{Flare-Free}   %& \colhead{} & \colhead{} \\   \colhead{} & \colhead{} & \multicolumn{2}{c}{Observation Length} %\colhead{Observation} & \colhead{Length}   & \colhead{Total Counts} & \colhead{Count Rate (ct s$^{-1}$)} \\ %\cline{3-4}  \colhead{Date} & \colhead{ObsID} & \colhead{Original\tablenotemark{a}} & \colhead{Analyzed\tablenotemark{b}} %\colhead{Length\tablenotemark{a}} & \colhead{Length}   & \colhead{Src / Bkgnd} & \colhead{Src / Bkgnd} }   \startdata  2000 Feb & 95 & 42.1 ks & 32.4 ks %(0.6 - 1.1 ct/s)   & 139 / 103 & 0.0043 / 0.0022 \\  2005 Aug & 5479 & 39.6 ks & 39.6 ks %(0.7 - 1.2 ct/s)   & 376 / 143 & 0.0095 / 0.0036 \\  2013 Dec & 14656 & 29.7 ks & 29.4 ks %(0.7 - 1.0 ct/s)   & 434 / 62 & 0.0148 / 0.0021 \\  \enddata  \tablenotetext{a}{Actual length of exposure.}  \tablenotetext{b}{Exposure length after removal of background flares.}  %\tablenotetext{a}{Each observation was checked for background flares; after removal of such events, 32.4 ks were kept for ObsID 95, 39.6 ks kept for ObsID 5479, and 29.4 ks kept for ObsID 14656.}  %% Include any \tablenotetext{key}{text}, \tablerefs{ref list},  %% or \tablecomments{text} between the \enddata and   %% \end{deluxetable} commands  %\tablecomments{}  \end{deluxetable}  The spectra were extracted from all three Chandra observations, and they are shown (binned to 10 cts/bin) in Figure \ref{fig:xrayspectrumlin} (linear axes) and Figure \ref{fig:xrayspectrumlog} (log axes).   We attempted fitting various models to the spectrum including a power-law model and thermal models. Models were fit with the column density as a free parameter and also with it fixed to the optical value, $N_{\mathrm{H}}$ = $(1.95 \pm 0.21) \times 10^{21}$ cm$^{-2}$ (converted from reddening value in \citet{2010ApJcantrell} using formula in \citet{2009MNRASguver}). The power-law model provided the best fit to our spectrum. Fitted values for the column density were largely consistent with the optical value, although not always for the thermal models. Calculated model parameters, both free and fixed, are shown in Table \ref{table:xraymodels} for all three observations of \thistarget{}.  \begin{figure}[htbp]  \centering  \subfigure[Linear axes; $x$- and $y$-axes are the same for all three panels.]{  \includegraphics[scale=0.5]{a0620spectra_grouped_linscale_150202.eps}  \label{fig:xrayspectrumlin}  }  \subfigure[Log axes; $x$- and $y$-axes are the same for all three panels.]{  \includegraphics[scale=0.5]{a0620spectra_grouped_logscale_150202.eps}  \label{fig:xrayspectrumlog}  }  \caption{X-ray spectra.}  \end{figure}  %\begin{figure}[htbp]  %\centering  %%\epsscale{1.03}  %\plotone{a0620spectra_grouped_linscale_150202.eps}  %\caption{X-ray spectra -- linear axes; $x$- and $y$-axes are the same for all three panels.}\label{fig:xrayspectrumlin}  %%\end{figure}  %%\begin{figure}[htbp]  %\centering  %%\epsscale{1.1}  %\plotone{a0620spectra_grouped_logscale_150202.eps}  %\caption{X-ray spectra -- log axes; $x$- and $y$-axes are the same for all three panels.}\label{fig:xrayspectrumlog}  %\end{figure}  \begin{deluxetable}{ccccc}  \tablewidth{0pt}  \tablecaption{Modeling of X-ray data for \thistarget{} \label{table:xraymodels}}  \tablehead{\colhead{ObsID} & \colhead{$N_{\mathrm{H}}$} & \colhead{Photon Index /} & \colhead{Amplitude /} & \colhead{$\chi^{2}_{\mathrm{red}}$} \\   \colhead{} & \colhead{($10^{21} \mathrm{cm}^{-2}$)} & \colhead{Temperature (keV)} & \colhead{Normalization} & \colhead{} \\  \colhead{} & \colhead{} & \colhead{} & \colhead{($\times 10^{-6}$)} & \colhead{} }   \startdata  \multicolumn{5}{c}{Power Law}\\%, Separate parameters for each observation} \\  %\cutinhead{Power Law}  %95 & $1.42^{+1.14}_{-0.92}$ & $1.74^{+0.44}_{-0.37}$ & $4.68^{+2.27}_{-1.53}$ & 0.49 \\  %5479 & $2.48^{+0.73}_{-0.64}$ & $2.36^{+0.30}_{-0.26}$ & $22.89^{+6.15}_{-4.70}$ & \\  %14656 & $2.03^{+0.75}_{-0.65}$ & $2.00^{+0.23}_{-0.21}$ & $33.99^{+8.20}_{-6.44}$ & \\  %%\hline  %95 & 1.95 [fixed] & $1.91^{+0.24}_{-0.22}$ & $5.58^{+0.83}_{-0.84}$ & 0.48 \\  %5479 & 1.95 [fixed] & $2.16^{+0.13}_{-0.13}$ & $19.14^{+1.64}_{-1.64}$ & \\  %14656 & 1.95 [fixed] & $1.97^{+0.12}_{-0.12}$ & $33.18^{+2.97}_{-2.97}$ & \\  %\hline  \multicolumn{5}{c}{Bremsstrahlung}\\%, Separate parameters for each observation} \\  %%\hline  %95 & $0.96^{+0.81}_{-0.63}$ & $6.46^{+18.26}_{-3.29}$ & $5.46^{+1.72}_{-1.08}$ & 0.51 \\  %5479 & $1.40^{+0.49}_{-0.42}$ & $2.65^{+1.05}_{-0.68}$ & $22.27^{+5.52}_{-3.98}$ & \\  %14656 & $1.17^{+0.54}_{-0.46}$ & $4.47^{+2.11}_{-1.24}$ & $34.30^{+6.00}_{-4.46}$ & \\  %%\hline  %95 & 1.95 [fixed] & $3.69^{+2.64}_{-1.32}$ & $7.15^{+1.36}_{-1.15}$ & 0.55 \\  %5479 & 1.95 [fixed] & $2.12^{+0.53}_{-0.40}$ & $27.21^{+3.97}_{-3.40}$ & \\  %14656 & 1.95 [fixed] & $3.36^{+0.94}_{-0.68}$ & $41.09^{+4.60}_{-4.09}$ & \\  %\hline  %%\vspace{2pt}  \multicolumn{5}{c}{Blackbody}\\%, Separate parameters for each observation} \\  %%\hline  %95 & $0.00^{+0.45}$ & $0.61^{+0.11}_{-0.10}$ & $12.01^{+9.80}_{-4.68}$ & 0.96 \\  %5479 & $0.00^{+0.15}$ & $0.54^{+0.02}_{-0.13}$ & $48.58^{+32.09}_{-3.00}$ & \\  %14656 & $0.00^{+0.23}$ & $0.66^{+0.02}_{-0.12}$ & $46.12^{+27.98}_{-2.73}$ & \\  %%\hline  %95 & 1.95 [fixed] & $0.56^{+0.11}_{-0.12}$ & $18.22^{+21.91}_{-8.28}$ & 1.34 \\  %5479 & 1.95 [fixed] & $0.37^{+0.05}_{-0.04}$ & $248.84^{+163.40}_{-96.18}$ & \\  %14656 & 1.95 [fixed] & $0.54^{+0.05}_{-0.05}$ & $109.07^{+48.26}_{-30.24}$ &   \enddata  %%% Include any \tablenotetext{key}{text}, \tablerefs{ref list},  %%% or \tablecomments{text} between the \enddata and   %%% \end{deluxetable} commands  \tablecomments{\textbf{need to paste in updated numbers}}  \end{deluxetable}  %  %We used the Sherpa task \texttt{sample\_flux}, the model with power-law photon index $\Gamma$ = ?.?? $\pm$ ?.??, and fixed column density $N_{\mathrm{H}}$ = $(1.95 \pm 0.21) \times 10^{21}$ cm$^{-2}$, to calculate the flux and the uncertainty in the energy range 1-10 keV. This gave $F_{\mathrm{1-10}}$ = ??.?? $\pm$ ??.?? erg s$^{-1}$ cm$^{-2}$. Using the known distance of 1.06 $\pm$ 0.12 kpc and black hole mass of 6.6 $\pm$ 0.25 M$_{\sun}$ \citep{2010ApJcantrell}, we calculated L$_{\mathrm{X}}$ = ??.?? erg s$^{-1}$, or $10^{-??}$ L$_{\mathrm{X}}$/L$_{\mathrm{Edd}}$. Fluxes and luminosities for the previous two observations, calculated in the same way, are given in Table \ref{table:xrayflux}.  After determining the best-fitting model for each spectrum, we calculated the $1 - 10$ keV flux and luminosity, which are shown for all three observations in Table \ref{table:xrayflux}.  %in the energy range , fixing the column density to the optical value given above. We used the known distance of 1.06 $\pm$ 0.12 kpc and black hole mass of 6.6 $\pm$ 0.25 M$_{\sun}$ \citep{2010ApJcantrell} to calculate the luminosity and the Eddington fraction. Results of these calculations are shown in Table \ref{table:xrayflux}.  \begin{deluxetable}{cccc}  \tablewidth{0pt}  \tablecaption{X-ray Fluxes and Luminosities for \thistarget{} \label{table:xrayflux}}  \tablehead{\colhead{Date} & \colhead{Flux\tablenotemark{a}} & \multicolumn{2}{c}{Luminosity\tablenotemark{b}} \\ %\cline{3-4}  \colhead{} & \colhead{(erg s$^{-1}$ cm$^{-2}$)} & \colhead{(erg s$^{-1}$)} & \colhead{($L_{\mathrm{X}}/L_{\mathrm{Edd}}$)} }   \startdata  2000 Feb & & & \\  2005 Aug & & & \\  2013 Dec & & & \\  \enddata  \tablenotetext{a}{Using $N_{\mathrm{H}}$ = $(1.95 \pm 0.21) \times 10^{21}$ cm$^{-2}$; see \S\ref{sect:obs-xray} for details.}%, converted from reddening value given in \citet{2010ApJcantrell} as described in \S\ref{sect:obs-xray}}  \tablenotetext{b}{Using distance $d = 1.06 \pm 0.12$ kpc and black hole mass $M_{\mathrm{BH}} = 6.6 \pm 0.25$ M$_{\sun}$ \citep{2010ApJcantrell}.}  \end{deluxetable}  \subsection{Optical and Near-Infrared Observations}\label{sect:obs-oir}  Optical and near-infrared observations were taken on the \textit{SMARTS} 1.3m telescope \citep{2012AJbuxton} at Cerro-Tololo InterAmerican Observatory.   For this project \thistarget{} was observed in $B$, $V$, $I$, $J$, $H$, and $K$ using the dual-channel imager ANDICAM.   \thistarget{} was observed continuously for   $\sim$6 hours on the night of 2013 Dec 8/9, scheduled to coincide with the \textit{Chandra} X-ray observation. We also observed \thistarget{} in those same filters a few times a night for approximately a week before and a week after the \textit{Chandra} X-ray observation, to be sure we would be able to identify whether the target was optically ``active'' or ``passive'' \citep{2008ApJcantrell} on the night of our multiwavelength campaign.  %% [More details, prob'ly not necessary in paper:   %% Each OIR 'observation' consisted of one frame in each of the six filters, taken as follows: B, V, and I exposure times were 300, 240, and 240 sec, respectively. J, H, and K observations were done as a series of 6 or 7 dithered 30-sec exposures which were taken simultanously with the optical data (B & K together, V & J together, I & H together). In each IR filter, each set of dithered frames was sky-subtracted, aligned, and combined in order to produce one final frame, and photometry was done on these sky-subtracted, combined frames. This sequence using all six filters was repeated continuously for the entire ~six hour period in which \thistarget{} was visible at CTIO.]  Optical and infrared (OIR) data were reduced and photometry was done using standard tasks in IRAF, following the procedures in \citet{2008ApJcantrell,2010ApJcantrell}.   %% Differential photometric errors averaged ?.?? in each filter, and absolute calibration errors were approximately ?.??.   OIR magnitudes were dereddened using $E(B-V)=0.29 \pm 0.03$ \citep{2010ApJcantrell} and $R=3.1$. Extinction values $A_{\lambda}$ were calculated using $A_{\lambda}/A_{V} = a(x) + b(x)/R_{V}$, with relations for $a(x)$ and $b(x)$ from \citet{1994ApJodonnell} for the optical and \citet{1989ApJcardelli} for the infrared.   %% using A_V = 0.8835 \pm ??, the central wavelengths of the SMARTS OIR filters, and the conversion factors given by XXX. Both the observed magnitudes of the source and the calculated stellar-only magnitudes from ELC were dereddened using these extinction values.   Dereddened magnitudes were converted to flux density in Jy using the zero points given in \citet{1998A&Abessell} (optical), \citet{1978ApJfrogel}, and \citet{1982AJelias} (infrared). Magnitudes and flux densities, as-observed and dereddened, are shown in Table \ref{table:oirdata}.  \begin{deluxetable}{ccccc}  \tablewidth{0pt}  \tablecaption{Optical/near-infrared measurements of \thistarget{} \label{table:oirdata}}  \tablehead{\colhead{} &   \multicolumn{2}{c}{As Observed} &   \multicolumn{2}{c}{Dereddened} \\  \colhead{Filter} & \colhead{Magnitude} & \colhead{Flux Density} & \colhead{Magnitude} & \colhead{Flux Density} \\   %\colhead{} & \colhead{} & \colhead{($\mu$Jy)} & \colhead{} & \colhead{($\mu$Jy)} } %%% fluxes in microJy  \colhead{} & \colhead{} & \colhead{(mJy)} & \colhead{} & \colhead{(mJy)} } %%% fluxes in milliJy  \startdata  \multicolumn{5}{c}{Total} \\  $B$ & 18.81 & 0.121 & 17.64 & 0.357 \\% $^{+0.054}_{-0.047}$ \\  $V$ & 17.81 & 0.274 & 16.91 & 0.624 \\% $^{+0.055}_{-0.051}$ \\  $I$ & 16.18 & 0.815 & 15.64 & 1.34 \\% $^{+0.171}_{-0.152}$ \\  $J$ & 15.21 & 1.38 & 14.96 & 1.74 \\% $^{+0.155}_{-0.142}$ \\  $H$ & 14.64 & 1.37 & 14.48 & 1.59 \\% $^{+0.146}_{-0.133}$ \\  $K$ & 14.25 & 1.23 & 14.15 & 1.35 \\% $^{+0.464}_{-0.346}$ \\  %\multicolumn{5}{c}{Star-only} \\  %$B$ & & & & \\  %$V$ & 18.49 & 0.145 & 17.60 & 0.331 \\  %$I$ & 16.78 & 0.467 & 16.24 & 0.769 \\  %$J$ & & & & \\  %$H$ & 14.99 & 0.992 & 14.83 & 1.15 \\  %$K$ & & & & \\  \multicolumn{5}{c}{Nonstellar Only} \\  $B$ & & & & \\  $V$ & & 0.129 & \nodata & 0.293 \\  $I$ & & 0.348 & \nodata & 0.571 \\  $J$ & & & & \\  $H$ & & 0.378 & \nodata & 0.438 \\  $K$ & & & & \\  \enddata  %% Include any \tablenotetext{key}{text}, \tablerefs{ref list},  %% or \tablecomments{text} between the \enddata and   %% \end{deluxetable} commands  \tablecomments{\textbf{\textit{rearrange: group by Mag or Flux, then give as-obs. and dered. \\ also: is it worth converting nonstellar flux back to mags to put in this table?}}}  \end{deluxetable}  %%%%%%%%%%%%%%%%%%%%%%%%%  %\subsection{Constructing the S.E.D.}\label{sect:constructingsed}  %We constructed our SED in the following manner.  %  %For the \textit{VLA} radio data, we simply used the flux density we calculated in each of the frequency bands we observed.   %  %For the \textit{SMARTS} OIR data, we used the median of the dereddened flux of the source in each filter.   %Error bars are simply the standard deviation of the observations (data points) in that filter.   %Medians and uncertainties were calculated separately for the star-only flux and the nonstellar flux (see description below), in the same manner.  %%%%%The error bars shown for the OIR points are %were calculated as %%uncertainty =   %%%%$\sigma/\sqrt{N}$, where $\sigma$ is the standard deviation and $N$ is the number of observations (data points) in that filter.   %  %%For the \textit{Chandra} X-ray data, we used the same procedure %Sherpa task [???],   %%as above, this time calculating the flux in four narrower energy bins: 1-3 keV, 3-5 keV, 5-7 keV, and 7-10 keV. Uncertainties for each of these fluxes were calculated in the same manner as described above for the 1-10 keV total flux.   %  %For the \textit{Chandra} X-ray data, we used the % Sherpa task [???],   %same procedure described above for the total 1-10 keV flux, calculating the flux and associated uncertainties in four narrower energy bins: 1-3 keV, 3-5 keV, 5-7 keV, and 7-10 keV. %Uncertainties for each of these fluxes were calculated in the same manner as described above for the 1-10 keV total flux.   %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%  \subsubsection{Subtracting the Star}\label{sect:star-sub}  We wanted to examine the spectral energy distribution (SED) for \thistarget{} for nonstellar emission only, without contamination from the secondary star. Therefore we used the Ellipsoidal Light Curve code \citep{2000A&Aorosz} and the stellar parameters given in \citet{2010ApJcantrell} to generate star-only ellipsoidal light curves for each of the six filters in which we observed \thistarget{}. These star-only light curves were normalized to the zero-disk stellar magnitudes given in \citet{2010ApJcantrell},   %All normalized star-only ELC light curves were   then dereddened and converted to flux densities in the same manner as described above. %in Sect. \ref{sect:obs-oir}.   %% extra[neous] details:  %% Cantrell et al only give zero-disk magnitudes for the V, H, and I bands. However, in determining the zero-disk value for the I band he illustrates a method for extending the spectroscopically-known information in V and H to other bands. We have used this method to extrapolate disk fractions, and therefore also zero-disk magnitudes, into the B, J, and K filters.   Star-only flux densities were subtracted from total observed flux densities to give the nonstellar flux density for each observation. These nonstellar values are shown in Table \ref{table:oirdata}, along with both the observed and the dereddened total OIR emission. %The median of the observations was then calculated for each type of emission in each filter, and the uncertainty on that median was determined in the same manner as described just above.   \subsection{Radio Observations}\label{sect:obs-radio}  We observed \thistarget{} with the \textit{Karl G. Jansky Very Large Array} (\textit{VLA}) on 2013 December 9, from approximately 03:28 to 09:27 UT, with the array in 'B' configuration. We observed in the %C-band (8-bit samplers) and K-band (3-bit samplers).   C-band and K-band, splitting   %We split   our C-band observations into two 1-GHz basebands centered at %, centering one at   5.25 GHz and %the other at   7.45 GHz. %Using the 3-bit samplers for the K-band allowed us to get a full bandwidth of 8 GHz, centered at 22 GHz.   %% We observed several other sources for calibration purposes: 3C147 was our flux density calibrator, while J0641-0320 and J0656-0323 were secondary calibrators.   %% The total observation time was split so that approximately an hour was spent on-source in each band, and the remaining time was   %% The observation was setup so that we got approximately an hour on-source at C-band and an hour at K-band, while the remaining time was used observing several calibrator sources: 3C147, J0641-0320, and J0656-0323.  Our observations totaled just over an %approximately one   hour on-source in each of the C- and K-bands, with the remaining time used to observe several calibrator sources: 3C147, J0641-0320, and J0656-0323.  %Each band (5.25, 7.45, 22 GHz) was processed and imaged separately, and all processing and analysis were done using the Common Astronomy Software Applications (CASA v4.2) package \citet{2007ASPCmcmullin}.  All processing and analysis were done using the Common Astronomy Software Applications (CASA, v4.2.1) package \citep{2007ASPCmcmullin}.   Each band (5.25, 7.45, 22 GHz) was processed and imaged separately. For each, RFI was removed and then data were calibrated and imaged\footnote{Imaging was done using the \texttt{clean} task in multi-frequency synthesis mode, with two Taylor terms and Briggs weighting (robustness parameter = 1.0)}.   %, the data were calibrated, and then imaging was done using the \texttt{clean} task in multi-frequency synthesis mode with two Taylor terms and Briggs weighting (robustness parameter = 1.0).   \textbf{\textit{[[include image or contour plot]]}}  The rms of the noise was calculated in a large source-free box ($\sim$XX arcsec on a side) to the south-east of \thistarget{}, and the flux density of \thistarget{} was calculated using an ellipse-fitting routine. Two additional sources were detected to the north and north-east of \thistarget{}, and the flux densities of each of these was also calculated in the same way. Flux densities, and their associated uncertainties, for all three sources in all three frequency bands are shown in Table \ref{table:radioflux}.  \begin{deluxetable}{cccc}%c}  \tablewidth{0pt}  \tablecaption{Radio Flux Densities for \thistarget{} and Neighboring Sources \label{table:radioflux}}  \tablehead{\colhead{Source} %& \colhead{Coordinates}   %& \colhead{Flux Density} & \colhead{} & \colhead{} \\   & \colhead{5.25 GHz} & \colhead{7.45 GHz} & \colhead{22 GHz} \\   \colhead{} %& \colhead{}   & \colhead{($\mu$Jy)} & \colhead{($\mu$Jy)} & \colhead{($\mu$Jy)} } %%% flux in microJy  %\colhead{} & \colhead{} & \colhead{(mJy)} & \colhead{(mJy)} & \colhead{(mJy)} } %%% flux in milliJy  \startdata  \thistarget{} %&   & $21.6 \pm 4.4$ & $9.1 \pm 4.5$ & \\  N Source %&   & $75.4 \pm 4.4$ & $46.5 \pm 4.5$ & \\  NE Source %&   & $53.9 \pm 4.4$ & $69.6 \pm 4.5$ & \\  \enddata  \tablecomments{still need 22 GHz values}  %% Include any \tablenotetext{key}{text}, \tablerefs{ref list},  %% or \tablecomments{text} between the \enddata and   %% \end{deluxetable} commands  %\tablecomments{\textbf{QUESTION FOR READER: is this table actually useful to have in the paper?} }  \end{deluxetable}