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Changeset 39858 for trunk


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Timestamp:
Dec 14, 2016, 2:52:39 PM (10 years ago)
Author:
watersc1
Message:

Final final draft.

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1 edited

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  • trunk/doc/release.2015/ps1.detrend/detrend.tex

    r39854 r39858  
    6565E.~A. Magnier,\altaffilmark{\IfA}
    6666P.~A. Price,\altaffilmark{\Princeton}
     67K.~C. Chambers,\altaffilmark{\IfA}
    6768H.~A. Flewelling,\altaffilmark{\IfA}
    6869M.~E. Huber,\altaffilmark{\IfA}
     70R.~H. Lupton,\altaffilmark{\Princeton}
     71A. Rest,\altaffilmark{\STSCI}
    6972W.~E. Sweeney,\altaffilmark{\IfA}
    7073J.~L. Tonry, \altaffilmark{\IfA}
    71 K.~C. Chambers,\altaffilmark{\IfA}
    72 R.~H. Lupton,\altaffilmark{\Princeton}
    73 A. Rest,\altaffilmark{\STSCI}
    7474W.~M. Wood-Vasey,\altaffilmark{\Pitt}
    7575PS1 Builders
     
    128128This is the third in a series of seven papers describing the Pan-STARRS1
    129129Surveys,
    130 the data reduction techiques and the resulting data products. This paper (Paper III)
     130the data reduction techniques and the resulting data products. This paper (Paper III)
    131131describes the details of the pixel processing algorithms, including
    132132detrending, warping, and adding (to create stacked images) and subtracting
     
    139139%Magnier et al. 2017 (Paper II)
    140140%Pan-STARRS Data Processing Stages
    141 \citet[][Paper II]{magnier2017c}
    142 describes how the various data processing stages are organised and
     141\citet[][Paper II]{magnier2017a}
     142describes how the various data processing stages are organized and
    143143implemented
    144144in the Imaging Processing Pipeline (IPP), including details of the
     
    150150%Magnier et al. 2017 (Paper IV)
    151151%Pan-STARRS Pixel Analysis : Source Detection
    152 \citet[][Paper IV]{magnier2017a}
     152\citet[][Paper IV]{magnier2017b}
    153153describes the details of the source detection and photometry, including
    154154point-spread-function and extended source fitting models, and the
     
    156156%Magnier et al. 2017 (Paper V)
    157157%Pan-STARRS Photometric and Astrometric Calibration
    158 \citet[][Paper V]{magnier2017b}
     158\citet[][Paper V]{magnier2017c}
    159159describes the final calibration process, and the resulting photometric and
    160160astrometric quality.
    161 The Pan-STARRS1 filters and photometric system has already been described
    162 in detail in \cite{2012ApJ...750...99T}.
    163161%Flewelling et al. 2017 (Paper VI)
    164162%Pan-STARRS 1 Database and Data Products
     
    173171data products specific to that survey. The Medium Deep Survey is not part
    174172of Data Release 1. (DR1)
     173The Pan-STARRS1 filters and photometric system has already been described
     174in detail in \cite{2012ApJ...750...99T}.
    175175
    176176
     
    280280
    281281% Note taken verbatim from Ken's Paper 1.
    282 \textit{Note: These papera are being placed on the arXiv.org to
     282\textit{Note: These papers are being placed on the arXiv.org to
    283283  provide crucial support information at the time of the public
    284284  release of Data Release 1 (DR1).  We expect the arXiv versions to be
    285   updated prior to submission and there could be significant
    286   variations with the refereed papers.  We apologize for the
    287   inconvience.}
     285  updated prior to submission to the Astrophysical Journal in January
     286  2017.  Feedback and suggestions for additional information from early
     287  users of the data products are welcome during the submission and
     288  refereeing process.}
    288289
    289290% Discuss 2-phase/3-phase device differnces
     
    372373between exposures.
    373374
    374 Both of these types of persistance trails are measured and optionally
     375Both of these types of persistence trails are measured and optionally
    375376repaired via the \ippprog{burntool} program.  This program does an
    376377initial scan of the images, and identifies objects with pixel values
     
    380381that this is the functional form of this persistence effect.  This
    381382also matches the expectation that a constant fraction of charge is
    382 incompletely transfered at each shift beyond the persistence
     383incompletely transferred at each shift beyond the persistence
    383384threshold.  Once this fit is done, the model can be subtracted from
    384385the image, and the location of the star is stored in a table along
     
    396397to expire.
    397398
    398 The main concern with this method of correcting the persistance trails
     399The main concern with this method of correcting the persistence trails
    399400is that it is based on fits to the raw image data, which may have
    400401other signal sources not determined by the persistence effect.  The
    401402presence of other stars or artifacts along the path of the burn can
    402403result in a poor model to be fit, resulting in either an over- or
    403 under-subtraction of the persistance burn.  For this reason, the image
     404under-subtraction of the persistence burn.  For this reason, the image
    404405mask is marked with a value indicating that this correction has been
    405406applied.  These pixels are not fully excluded, but they are marked as
     
    613614along the x-pixel axis binned along the full y-axis of the first row
    614615of cells.  The raw data is shown, illustrating the positional
    615 depenendence the dark signal has on the image values.  In addition,
     616dependence the dark signal has on the image values.  In addition,
    616617both the correct B-mode dark and incorrect A-mode dark have been
    617618applied to this image, showing that although both correct the bulk of
     
    687688video dark for older data simply as $VD_{2009} = D_{2009} - D_{Modern}
    688689+ VD_{Modern}$ produces a satisfactory result that does not
    689 oversubtract the amplifier glow.  This is shown in figure
     690over subtract the amplifier glow.  This is shown in figure
    690691\ref{fig:video_darks}, which shows video cells from before 2012-05-16,
    691692corrected with both the standard and video darks, with the early video
     
    706707%  \end{subfigure}
    707708  \end{minipage}
    708   \caption{An example of the video dark model application to exposure o5677g0123o, OTA22 (2011-04-26, 43s \gps{} filter), which has a video cell located in cell xy16.  The left panel shows the image data mosaicked to the OTA level, and has had the static mask applied, the overscan subtracted, the detector non-linearity corrected, and a regular dark applied.  The right panel, shows the same exposure with a video dark applied instead of the standard dark.  The main impact of this change is the improved correction of the corner glows, which are oversubtracted with the standard dark.}
     709  \caption{An example of the video dark model application to exposure o5677g0123o, OTA22 (2011-04-26, 43s \gps{} filter), which has a video cell located in cell xy16.  The left panel shows the image data mosaicked to the OTA level, and has had the static mask applied, the overscan subtracted, the detector non-linearity corrected, and a regular dark applied.  The right panel, shows the same exposure with a video dark applied instead of the standard dark.  The main impact of this change is the improved correction of the corner glows, which are over subtracted with the standard dark.}
    709710  \label{fig:video_darks}
    710711\end{figure}
     
    15351536distribution with a Gaussian.  All pixels that were masked in the
    15361537initial calculation are unmasked, and a histogram is again constructed
    1537 of the values, with a binsize set to $\sigma_{guess} / \left( N_{50} /
    1538 500 \right)$.  With this binsize, we expect that a bin at $\pm 2
     1538of the values, with a bin size set to $\sigma_{guess} / \left( N_{50} /
     1539500 \right)$.  With this bin size, we expect that a bin at $\pm 2
    15391540\sigma$ will have approximately 50 input points, which gives a
    15401541Poissonian signal to noise estimate around 7.  In the case where
     
    15721573disk as a $13\times{}13$ image with header entries listing the binning
    15731574used.  The full scale background image is then constructed by
    1574 binlinearly interpolating this binned model, and this is subtracted
     1575bilinearly interpolating this binned model, and this is subtracted
    15751576from the science image.  Each object in the photometric catalog has a
    15761577SKY and SKY\_SIGMA value that is the evaluation of this model at the
     
    18601861Once individual exposures have been warped onto a common projection
    18611862system, they can then be combined pixel-by-pixel regardless of their
    1862 original orientation.  Creating a stacked image by coadding the
     1863original orientation.  Creating a stacked image by co-adding the
    18631864individual warps increases the signal to noise, allowing for the
    18641865detection of objects that would not be sufficiently significant to be measured from a single image.
     
    22012202
    22022203
    2203 Finally, a second pass at rejecting pixelsis conducted, by growing the
     2204Finally, a second pass at rejecting pixels is conducted, by growing the
    22042205current list to include pixels that are neighbors to many rejected
    22052206pixels.  The ISIS kernel used in the previous step is again used to
     
    23072308    frame is largely unmasked after combining inputs, with the only
    23082309    remaining masks falling on the cores of bright stars, and in small
    2309     regions around the brighest objects where the overlapping of
     2310    regions around the brightest objects where the overlapping of
    23102311    diffraction spike masks have removed all inputs.}
    23112312
     
    25072508%\czwdraft{Not happy with this.}
    25082509
    2509 The Pan-STARRS1 PV3 processing has reduced an unprecidented volume of
     2510The Pan-STARRS1 PV3 processing has reduced an unprecedented volume of
    25102511image data, and has produced a catalog for the $3\Pi$ Survey
    25112512containing hundreds of billions of individual measurements of
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