Data Set Information
DATA_SET_NAME EPOXI EXOPLANET TRANSIT OBS - HRIV STELLAR PHOTOMETRY V1.0
DATA_SET_ID DIF-X-HRIV-5-EPOXI-EXOPLANETS-PHOT-V1.0
NSSDC_DATA_SET_ID
DATA_SET_TERSE_DESCRIPTION
DATA_SET_DESCRIPTION Data Set Overview : This data set contains aperture photometry of known transiting planet systems GJ 436, HAT-P-4, HAT-P-7, TrES-2, TrES-3, and WASP-3 derived from radiance calibrated (RADREV), clear #6 filtered (350 to 950 nm bandpass) images acquired by the Deep Impact High Resolution Visible CCD from 22 January through 31 August 2008 during the EPOCh phase of the EPOXI mission. The photometry data were derived from time series of continuous 50-second integrations used to observe each system for about three weeks, typically covering five or more transits as well as secondary eclipses. Photometry of EPOCh targets XO-2 and XO-3 was not produced because transits were not observed due to spacecraft telecommunication problems. Data Reduction : The HRIV CCD detector had changed over time while in space, and the ground-based flat fields used by the EPOXI radiance calibration pipeline (see Klaasen et al. 2008 [KLAASENETAL2006]) were not adequate for precision stellar photometry. Therefore the EPOCh team used an independent bootstrap procedure, fitting aperture photometry derived from the radiance images to a 2-D spline, to define corrections to the flat-field calibration. For descriptions of this process as well as discussions about the photometric results, see Ballard et al. 2009 [BALLARDETAL2009B], Christiansen et al. 2009 [CHRISTIANSENETAL2009], Ballard et al. 2010 [BALLARDETAL2010, BALLARDETAL2010B], Ballard et al. 2011 [BALLARDETAL2011], and Christiansen et al. 2010 [CHRISTIANSENETAL2010] & [CHRISTIANSEETAL2010B]. Additionally the EPOCh team summarized the calibration steps and photometric errors by target in EPOCH_TRANSIT_OBS_DESC.PDF found the DOCUMENT directory of this data set. Data Products : The derived photometry for each target is provided in two different formats: One product is a flat ASCII table (*.TAB) and the other is a FITS binary table (*.FIT) where the data are located in the first extension. Each product has a detached PDS label (*.LBL) describing its file format. Each photometry table contains four columns. The most relevant data are in column 1, the UTC Barycentric Julian Date at mid-observation, and column 2, the measured flux. Column 3 gives the day of year in 2008, and column 4 gives the name of the radiance calibrated (RADREV) image file from which the photometry flux point was extracted. Fluxes are normalized such that the non-transit data points are near unity. Null photometry data points (for example, images where the star was not in the field of view because of pointing deviations) are not included in the tables. The UTC Barycentric Julian Date provides the time at which light from the mid-point of an observation (that is, a photometry point), reached the solar system barycenter. The 'Report on the Calibration of EPOXI spacecraft timing and reduction to Barycentric Julian Date' in the DOCUMENT directory describes how the values were computed. Please note the START_TIME and SPACECRAFT_CLOCK_START_TIME keywords in each product label are set to the UTC time at the spacecraft and the spacecraft clock value at the beginning of the first observation in the photometry table. Likewise, STOP_TIME and SPACECRAFT_CLOCK_STOP_TIME are set to the UTC time at the spacecraft and the spacecraft clock value at the end of the last observation in the photometry table. Related PDS Data Sets : The following PDS data sets, available online at http://pds.nasa.gov, are related to this one and may be useful for research: DIF-X-HRIV-3-EPOXI-EXOPLANETS-V1.0 - This data set contains radiance calibrated HRIV extrasolar planet transit observations of GJ 436, HAT-P-4, HAT-P-7, TRES-2, TRES-3, WASP-3, XO-2, and XO-3 acquired during 2008. The EPOCh team used the reversibly calibrated images (known as 'RADREV') to derive the aperture photometry in this data set. DIF-CAL-HRIV-2-EPOXI-CALIBRATIONS-V1.0 - This data set contains the raw HRIV dark frames (image exposure IDs 9600000 and 9600001) and internal stimulator lamp images (exposure IDs 9600002 and 9600003) acquired to monitor changes in the CCD detector for EPOCh transit photometry purposes. The time series for each EPOCh target was typically bracketed by a set of dark and internal stimulator lamp frames to monitor changes in the CCD detector and to aid transit photometry. DIF-CAL-HRIV-6-EPOXI-STELLAR-PSFS-V1.0 - This data set contains one HRIV point spread function, produced by a drizzle method, for each of the EPOCh exoplanet transit targets. The EPOCh photometry team used these PSFs to locate the stellar position and fit the aperture photometry. See Barry et al. 2010 [BARRYETAL2010] for more information. DI-C-HRII/HRIV/MRI/ITS-6-DOC-SET-V3.0 - Deep Impact and EPOXI documentation set provides overviews of the EPOXI mission.
DATA_SET_RELEASE_DATE 2010-12-20T00:00:00.000Z
START_TIME 2008-01-22T12:22:53.769Z
STOP_TIME 2008-08-31T12:44:54.196Z
MISSION_NAME EPOXI
MISSION_START_DATE 2007-09-26T12:00:00.000Z
MISSION_STOP_DATE 2013-09-20T12:00:00.000Z
TARGET_NAME GJ 436
HAT-P-4
HAT-P-7
TRES-2
TRES-3
WASP-3
TARGET_TYPE STAR
INSTRUMENT_HOST_ID DIF
INSTRUMENT_NAME DEEP IMPACT HIGH RESOLUTION INSTRUMENT - VISIBLE CCD
INSTRUMENT_ID HRIV
INSTRUMENT_TYPE CCD CAMERA
NODE_NAME Small Bodies
ARCHIVE_STATUS ARCHIVED
CONFIDENCE_LEVEL_NOTE Confidence Level Overview : The EPOCh photometry team presented these data in Ballard et al. 2009 [BALLARDETAL2009B], Christiansen et al. 2009 [CHRISTIANSENETAL2009], Ballard et al. 2010 [BALLARDETAL2010], and Christiansen et al. 2010 [CHRISTIANSENETAL2010] & [CHRISTIANSEETAL2010B]. Review : This data set was peer reviewed at the PDS Small Bodies Node (SBN) 29 September 2010 with the stipulation that liens must be resolved before it could be certified for scientific use. Liens were resolved in December 2010, and the data set was certified for scientific use on 26 January 2011. This data set is archived at SBN and the Multi-Mission Archive at STScI (MAST).
CITATION_DESCRIPTION Christiansen, J.L., S. Ballard, D. Deming, D. Charbonneau, D.D. Wellnitz, and S.A. McLaughlin, EPOXI EXOPLANET TRANSIT OBS - HRIV STELLAR PHOTOMETRY V1.0, DIF-X-HRIV-5-EPOXI-EXOPLANETS-PHOT-V1.0, NASA Planetary Data System, 2010.
ABSTRACT_TEXT This data set contains aperture photometry of known transiting planet systems GJ 436, HAT-P-4, HAT-P-7, TrES-2, TrES-3, and WASP-3 derived from radiance calibrated, clear #6 filtered images acquired by the Deep Impact High Resolution Visible CCD from 22 January through 31 August 2008 during the EPOCh phase of the EPOXI mission. The photometry data were derived from time series of continuous 50-second integrations used to observe each system for about three weeks, typically covering five or more transits as well as secondary eclipses.
PRODUCER_FULL_NAME STEPHANIE MCLAUGHLIN
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