#****************************************************************************** # E.S.O. - VLT project # # "@(#) $Id: dicVISTA_PRIMARY.txt,v 1.24 2003/08/01 14:24:02 vltsccm Exp $" # # VISTA_PRIMARY dictionary # # Refer to appendix A of document VLT-SPE-ESO-17240-1676 for details. # # who when what # -------- -------- ---------------------------------------------- # pbunclark 2004-06-26 created. # #****************************************************************************** # # Notes # 1) The letters within () indicate the Class that keyword belongs to: # c = config # h = header # l = conf-log # p = private # s = setup # o = ops-log # DICTIONARY VISTA_PRIMARY "VISTA" "VISTA primary-header keywords" REVISION "$Revision: 0.5 $" CONTEXT "FITS" SIMPLE %c Standard FITS (NOST-100-2.0) (h). SIMPLE must be equal to "T" to conform to FITS. NAXIS %d number of axes of data array [cardinal] (h). VISTA data stored in multi-extension FITS, hence NAXIS=0 in primary header, NAXIS=2 in extension headers. BITPIX %d number of bits per pixel value (h). Number of bits used to store pixel values Standard values are defined in NOST-100.0 The value for VISTA IR will be 32 32-bit twos-complement binary integer, but there is no primary data so BITPIX is 8 in the primary header. EXTEND %c FITS file extension may be present (h). VIRCAM files will be multi-extension FITS, so EXTEND ='T' RA %.6f %HOURANG RA of telescope [degrees] (h). Telescope pointing Right Ascension, in ICRF, of rotator axis, expressed in decimal degrees. The comment field includes the value expressed in sexagesimal. DEC %.6f %DECLINATION Dec of telescope [degrees] (h). Telescope pointing declination, in ICRF, of rotator axis, expressed in decimal degrees. The comment field include the value exressed in sexagesimal. RADECSYS %s Name of celestial reference frame (h). Standard reference-frame name, will normally be 'ICRS'. Note, this implies the EQUINOX keyword is absent. EQUINOX %.1f Equinox of celestial reference frame [Year] (h). Equinox of reference frame, required for precessed reference frames, but obsolete for International Coordinate Reference System. ORIGIN %s European Southern Observatory (h). Observatory source of this file. The value is "ESO-PARANAL" for VISTA. TELESCOP %s ESO (h). ESO telescope code as defined in GEN-SPE-ESO-00000-0794 (ESO-VISTA). INSTRUME %s Instrument used (h). ESO acronym for the instrument used. VIRCAM for VISTA InfraRed Camera. OBJECT %s Target description (h). Identification of target observed. IMAGETYP %s Exposure type (h). Description of type of observation, ie OBJECT, DOMEFLAT, SKYFLAT, DARK,RESET. AIRMASS %.5f Averaged airmass (h). Average airmass for the optical axis during the exposure computed as described in GEN-SPE-ESO-00000-0794. DATE %s Date this file was written (h). UTC date on which this file was written. The following format shall be used: YYYY-MM-DDThh:mm:ss.sss DATE-OBS %s UTC date at start of exposure (h). UTC date of the start of the exposure. The format used is YYYY-MM-DDThh:mm:ss.sss UTC %.3f %TIME UTC s at start since midnight [seconds] (h). Universal Coordinated Time at start of the exposure in seconds elapsed since (UTC) midnight. The comment includes a civil representation of the value. REQTIME %.3f Requested integration time [seconds] (h). The requested integration time, from the observing system. The actual time will differ due to timing errors or use of an early END command. EXPTIME %.3f Actual integration time [seconds] (h). The integration time for a single observation (in the infrared this corresponds to DIT. Note that this does not represent the photon statistics). It may not match the requested integration time. LST %.3f %TIME LST seconds since midnight [sidereal] (h). Local Sidereal Time at start of the exposure in seconds elapsed since sidereal midnight. The comment includes a civil representation of the value. MJD-OBS %.8f Modified Julian Date at start [days] (h). Modified Julian Day of the start of the exposure. The MJD is related to the Julian Day (JD) via the formula: MJD = JD-2400000.5 The comment includes a civil representation of the date and time. 8 decimals are required for a precision of one millisecond, 5 decimals for a precision of one second. OBSERVER %s Name of observer (h). Given name, initial(s), family name of observer PI-COI %s Name(s) of proposer(s) Name(s) of proposer(s) (as opposed to observer) COMMENT %s (h). This keyword is used to include comments in the header. HISTORY %s (h). This keyword is used to include history information in the header. ESO-LOG %s (h). This keyword is used to include operations log entries in the header. Normally, log records that are written during the exposure are also repeated for information purposes in the header. Only the leftmost 71 characters of the log records are reproduced in this keyword. The equal sign "=" is not allowed as the first character in the comment. ORIGFILE %s Original File Name (h). Original file name delivered by data=acquisition system. ARCFILE %40s Archive File name (h). Unique Data Product ID within the ESO Data Flow System. It is composed of .YYYY-MM-DDTHH:MM::SS.sss.fits where is a unique data producer identifier (typically the name of instrument) and the date and time is set by the time of start of the exposure as as given through the MJD-OBS keyword in the FITS header. CHECKSUM %s ASCII 1s-complement checksum (h). 32 bit Cyclic Redundant Check (CRC) calculation of the frame. It uses the CCITT standard CRC polynomials. A description and C code can be found at http://archive.eso.org/DICB/checksum