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trunk/doc/release.2015/systematics.20140411/diffusion.tex
r40306 r40307 22 22 % \newcommand\oldtext[1]{\textbf{\color{light-gray}#1}} 23 23 \newcommand\oldtext[1]{\ignorespaces} 24 \newcommand\newtext[1]{\textbf{\color{blue}#1}} 24 % \newcommand\newtext[1]{\textbf{\color{blue}#1}} 25 \newcommand\newtext[1]{#1} 25 26 \newcommand\fixtext[1]{\textbf{\color{red}#1}} 26 27 … … 347 348 \cite{2013ApJS..205...20M,magnier2017.calibration}. As part of this 348 349 process, several flat-field corrections have been determined. For the 349 PV 2analysis discussed here, a flat-field correction determined during350 PV0 analysis discussed here, a flat-field correction determined during 350 351 the ubercal analysis \citep[see][]{2012ApJ...756..158S} consisted of 351 352 an $8\times 8$ grid of corrections for each GPC1 chip, corresponding … … 354 355 with modifications to the baffle structures or the system optics. The 355 356 critical point here is that the final effective flat-field image for 356 the PV 2dataset is based on a dome-flat at the highest resolution,357 the PV0 dataset is based on a dome-flat at the highest resolution, 357 358 with very low resolution (hundreds of pixels) corrections based on 358 359 photometry, resulting in photometric systematic uncertainties in the … … 360 361 \citep{2013ApJS..205...20M}. \newtext{We note that the PV3 analysis 361 362 used for the public release includes a flat-field correction 362 measured with a much finer spatial sampling than the PV 2analysis,363 measured with a much finer spatial sampling than the PV0 analysis, 363 364 with 40 CCD pixels per superpixel. As a result, some of the 364 fine-grained structure discussed below iscorrected in the public365 fine-grained structure discussed below are corrected in the public 365 366 release (see however the caveats in the discussion section below).} 366 367 … … 370 371 \citep{magnier2017.analysis}. These position measurements are 371 372 used in the astrometric analysis. The astrometric calibration is 372 discussed by \cite{magnier2017.calibration}; for the PV 2373 discussed by \cite{magnier2017.calibration}; for the PV0 373 374 dataset, the typical systematic floor is \approx 15 - 20 374 375 milliarcsecond for individual measurements of brighter stars. … … 643 644 strong in the (\gps,\rps,\ips) images, but nearly swamped by fringing 644 645 in \zps, and completely lost to fringing in \yps. A diagonal banding 645 pattern is also seen in \gps and \rps: this feature is thought to be due to646 pattern is also seen in \gps\ and \rps: this feature is thought to be due to 646 647 the lithography process used to generate the CCD. A blob can also 647 648 been seen covering 4 cells near the center of this chip; this is … … 904 905 \includegraphics[width=\figwidth]{\picdir/radial_p1_r.\plotext} 905 906 \caption{Radial run of the four tree-ring trends for \rps: smear 906 ($\sigma^2_{\mbox{major}} + \sigma^2_{\mbox{minor}}$), PSF magnitude 907 residuals ($\delta m_{PSF}$), flat-field, and astrometric residuals 908 ($\delta R$). } \label{fig:effects.vs.radius} 907 ($\sigma^2_{\mbox{major}} + \sigma^2_{\mbox{minor}}$, pixel$^2$), PSF magnitude 908 residuals ($\delta m_{PSF}$, magnitudes), flat-field (fractional 909 deviation), and astrometric residuals 910 ($\delta R$, arcseconds). } \label{fig:effects.vs.radius} 909 911 \end{center} 910 912 \end{figure*} … … 915 917 \begin{center} 916 918 \includegraphics[width=\figwidth]{\picdir/radial_p2_r.\plotext} 917 \caption{Radial run of the derivative of the smear ($\frac{\partial (\sigma^2_{major} + \sigma^2_{minor})}{\partial radius}$) 918 and astrometric residuals ($\delta R$) for \rps. 919 \caption{Radial run of the derivative of the smear 920 ($\frac{\partial (\sigma^2_{major} + \sigma^2_{minor})}{\partial 921 radius}$, pixels) 922 and astrometric residuals ($\delta R$, arcseconds) for \rps. 919 923 } \label{fig:dsmear.and.astrom} 920 924 \end{center} … … 928 932 \caption{Radial run of 929 933 the derivative of the astrometric residuals ($\frac{\partial \delta 930 R}{\partial radius}$) and the flat-field for \rps.} \label{fig:dastrom.and.flat} 934 R}{\partial radius}$, pixels pixel$^{-1}$) and the flat-field 935 (fractional deviation) for \rps.} \label{fig:dastrom.and.flat} 931 936 \end{center} 932 937 \end{figure*} … … 939 944 940 945 Second, the radial derivative of the smear is anti-correlated with the 941 radial component of the astrometric residuals 946 radial component of the astrometric residuals. 942 947 \newtext{Figure~\ref{fig:dsmear.and.astrom} shows the radial run of 943 948 $\frac{\partial (\sigma^2_{major} + \sigma^2_{minor})}{\partial radius}$ … … 1032 1037 \label{sec:discussion} 1033 1038 1034 The setrends measured above (Section~\ref{sec:tree.rings}) help to1039 The trends measured above (Section~\ref{sec:tree.rings}) help to 1035 1040 illuminate the underlying causes of these different effects. 1036 1041 … … 1201 1206 tree rings. These plate-scale changes introduce flat-field errors on 1202 1207 the scale of \approx 1 millimagnitude and astrometric errors on the 1203 scale of 2-3milliarcseconds. The observed relationship between the1208 scale of 5-10 milliarcseconds. The observed relationship between the 1204 1209 flat-field deviations and the radial derivative of the astrometric 1205 1210 deviations confirms this interpretation \citep[see also discussion … … 1282 1287 1283 1288 \bibliographystyle{apj} 1284 \bibliography{lib}{}1285 %\input{diffusion.bbl}1289 %\bibliography{lib}{} 1290 \input{diffusion.bbl} 1286 1291 1287 1292 \end{document}
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