PDS_VERSION_ID = PDS3 RECORD_TYPE = "STREAM" OBJECT = TEXT PUBLICATION_DATE = 2011-06-30 NOTE = "Description of the contents of the CALIB/ directory" END_OBJECT = TEXT END CALIB Directory Contents This file describes the contents of the calibration directory. The EPOXI calibration pipeline uses the files in this directory to calibrate raw data from the EPOXI mission; many of the files are duplicates of those for Deep Impact. The files are derived from analysis of pre-launch thermal-vacuum data as well as from in-flight calibrations performed during the Deep Impact and EPOXI missions. For more information about these files, the analyses, and the calibration pipeline, see the Deep Impact instrument calibration paper included on the Deep Impact and EPOXI documentation data set, DI-C-HRII/HRIV/MRI/ITS-6-DOC-SET-V3.0. The calibration data are provided as FITS image files or ASCII tables. The following file naming convention is used: CCCCC/IIIIII_YYMMDD_V_M_FFF.{FIT,TAB} | | | | | | | | | | | Optional filter number (1 through 9), temperature, | | | | | or place holder value such as '999' | | | | | | | | | Instrument image mode (1 through 9) or a place | | | | holder value of '0' to indicate all modes | | | | | | | File version number (1, 2, etc.) for the given | | | effective date | | | | | Effective date for using the file (not the file creation | | date). Multiple calibration files may exist for the same | | application, reflecting changes in the instrument as a | | function of time, and this field defines the start of the | | observation window where the file is used in the reduction | | process. It is used for all subsequent observation dates | | until a file with a later effective date supecedes its use. | | The value '000101' is used as a place holder, in which case, | | the file provides no useful information but is required to | | keep the pipeline running. | | | Instrument designation (e.g. HRIVIS for HRIV) | Directory for the type of calibration file (e.g. FLAT for flat fields) Here is an example of a complete file name, FLAT/HRIVIS_100201_1_1_9.FIT - FLAT Flat field - HRIVIS HRIV Instrument - 100201 Effective date of 2010-02-01; this flat can be applied to data acquired on 2010-02-01T00:00:00 UTC or later - 1 Version 1 of the file for the specified effective date - 1 Instrument image mode 1 - 9 Filter 9 - .FIT FITS file Calibration files are grouped into subdirectories by type: ABSCALVS -------- This subdirectory contains absolute calibration constants, one file for each filter, for converting raw DN/s to units of radiance W/(m**2 sr um) and then to I/F (observed radiance over input solar radiance at 1AU, unitless). ADCLUT ------ This subdirectory contains a lookup table for the correction of uneven bit weighting caused by the analog-to-digital conversion. The single table applies to all instrument modes. As of this archive, the corrections had not been derived. Therefore, the input pixel values are the same as the output values to prevent the automated calibration pipeline from changing the data. BADPIX ------ This subdirectory contains maps that identify bad pixels for all instrument modes. Bad pixels are set to a value of 1. Good pixels are set to 0. Pixels in the serial and parallel overclock columns and rows are flagged as good (0). For each image mode, there is one row of warm pixels near the top and bottom edge. These rows are flagged as bad (1). BIAS ---- This subdirectory contains bias correction maps for instrument modes 7 and 8 that do not have overclocks (used for bias subtraction for modes 1-6, and 9). DECOMPRS -------- This subdirectory contains the four 8-bit lookup tables used to decompress raw data numbers. DRKMODEL -------- This subdirectory contains mode-dependent files of physical parameters of the CCD for modeling the dark current. FILTERS ------- This subdirectory contains one transmission profile table for each filter. FLAT ---- This subdirectory contains flat fields for every combination of instrument mode and filter. PSF --- This subdirectory contains maps of the two-dimensional point-spread function (PSF) for all filters. The PSF can be used to deconvolve an out-of-focus HRIV image. QE -- This subdirectory contains the quantum efficiency curve for the CCD detector. XTALK ----- This subdirectory contains 3-D FITS files that provide the coefficients of polynomials specifying how much electronic cross-talk occurs between all possible ordered pairs of quadrants of an input HRIV image. There is one file for each instrument mode.