The ISOPHOT auto-analysis products are binary FITS tables in case of single pointing photometry and spectro-photometry or FITS images in case of mapping mode. All products consist of an ASCII header in which are stored:
Detailed descriptions of the headers as well as the FITS records of the products are given in Chapters 13 and 14. As the headers are in ASCII, the header information of the FITS files can be browsed with a `TYPE' (in VMS) or `more' (in unix) command.
For a quick look of the binary FITS table data, utilities are required to convert the binary contents of a FITS file into an ASCII file. For the single pointing photometry data, the tables are usually not very big, so that the ASCII file can immediately be downloaded in a general utility such as a spreadsheet.
Dedicated software to generate an ASCII file of the ISOPHOT auto analysis data is provided by IPAC by means of the `First Look' (FL) tool . For a description see:
http://www.iso.vilspa.esa.es/ ISO Explanatory Library PHT
It should be noted that the first look tool cannot read the products PPAS, PSAE, PLAE, PSAS, and PLAS. As an illustration we run on the AAR product of the observation retrieved from IDA (Section 11.1):
flpht -v -o out.txt ppap13001001.fitswhere out.txt is the output ASCII file with the following contents:
"First Look" generated by IPAC "flpht", version 5.0 on 2 Apr 2002 ppap13001001.fits created on 2001-08-18 by version OLP_10 at ESA --------------------------------------------------------------------------- Observer HHABING , Proposal HJHVEGA3 , Equinox 2000.0 AOT Target name RA DEC Obs Date Start UT End UT P03 HD 187642 19h50m47.06s +8d52m04.5s 26 Mar 96 14:10:12 14:17:28 Name of the AAR file : 'ppap13001001.fits' Primary FITS headers: ====================== AAR file Creation date : '2001-08-18' (DATE ) Type of attitude operation (P/R/T) : Pointed (ATTTYPE ) Chopper mode : 'TR ' (FPCMODE ) file does conform to FITS standard : T (SIMPLE ) number of bits per data pixel : 8 (BITPIX ) number of data axes : 0 (NAXIS ) FITS dataset may contain extensions : T (EXTEND ) COMMENT FITS (Flexible Image Transport System) format defined in Astronomy and COMMENT Astrophysics Supplement Series v44/p363, v44/p371, v73/p359, v73/p365. COMMENT Contact the NASA Science Office of Standards and Technology for the COMMENT FITS Definition document #100 and other FITS information. Data Origin : 'ESA ' (ORIGIN ) Telescope : 'ISO ' (TELESCOP) Instrument used : 'PHT ' (INSTRUME) COMMENT PHT-P point source photometry File name : 'PPAP13001001' (FILENAME) File version ID in ISO archive : '2570 ' (FILEVERS) SOC OLP system version : 'OLP_10 ' (OLPVERS ) SOC OLP CAL-G files version : 'CALG_70 ' (CALGVERS) Product not catalogued : 'PIPEPAR ' (USERNAME) Target ID as given by proposer : 'HD 187642' (OBJECT ) Proposer ID in ISO Mission DB : 'HHABING ' (OBSERVER) Equinox : 2000.0 (EQUINOX ) Telemetry rate in Kbps (Kbits/sec) : 32 (TMRATE ) Approx. UTC of start of observation : '96086141012' (EOHAUTCS) Approx. UTC of end of observation : '96086141728' (EOHAUTCE) AOT name : 'P03 ' (EOHAAOTN) Proposal ID : 'HJHVEGA3' (EOHAPLID) Observation sequence number : '01 ' (EOHAOSN ) Pointing sequence number : '00 ' (EOHAPSN ) Proposal category : '1 ' (EOHAPCAT) Calibration indicator : ' ' (EOHACIND) Target type : '003 ' (EOHATTYP) AOT-to-OCT logic version : '03.01 ' (AOTVERS ) UTC of start time of slew to intended target : '96086140828' (ATTUTCSL) UTC of time of first arrival at intended targe: '96086140947' (ATTUTCS ) On-target flag threshold (arc secs) : 10.0 (ATTOTFTH) Intended Right Ascension of instrument viewing: 297.69608 (ATTRA ) Intended DEClination (with ATTRA) : 8.86792 (ATTDEC ) Guide star reference number : 111435 (ATTGUIDE) Solar aspect angle (degrees) : 68.1 (ATTSAANG) CONTINGEncy flag(0=success; 1=target not acq'd: 0 (ATTERROR) UTC (whole seconds since 01-01-1989) : 228233412 (TREFUTC1) UTC (remaining fraction of second) : 1413920 (TREFUTC2) ISO Uniform Time Key (UTK) : 303969888 (TREFUTK ) ISO INSTRUMENT Time Key (ITK) : 0 (TREFITK ) ITK unit length in seconds : 0.00006103515630 (TREFITKU) Reference instrument J2000 right ascension (deg: 297.69608 (INSTRA ) Reference instrument J2000 declination (deg) : +8.86791 (INSTDEC ) Reference instrument J2000 roll angle (deg) : 90.90 (INSTROLL) RTA maximum severity level : 0 (ISRRSEV ) QLA maximum severity level : 0 (ISRQSEV ) RA-warning flag from IS user : 'ok ' (ISRRWARN) No. of out-of-soft-limit errors : 0 (ISRNOOSL) No. of out-of-hard-limit errors : 0 (ISRNOOHL) No. of monitor warnings : 1 (ISRNMW ) No. of command verification errors : 0 (ISRNCVW ) No. of bad telemetry errors : 0 (ISRNBTW ) No. of memory verification errors : 0 (ISRNMVW ) No. of severe QLA errors : 0 (ISRNSQLA) Corrected instrument RA (deg) : 297.696136 (CINSTRA ) Corrected instrument Dec (deg) : 8.867890 (CINSTDEC) Corrected instrument roll angle (deg) : 90.900002 (CINSTROL) On-source RA(deg) : 297.696136 (CONSCRA ) On-source Declination(deg) : 8.867890 (CONSCDEC) Version ID of each input file : '2517/EOHA130' (VERS1 ) Version ID of each input file : '2570/PP2S13001001' (VERS2 ) Version ID of each input file : '2420/PPPSF' (VERS3 ) Version ID of each input file : '2322/PCPSF' (VERS4 ) Version ID of each input file : '2022/PFLUXCONV' (VERS5 ) Extension Table Column Formats: ================================ Binary table FITS extension : 'BINTABLE' (XTENSION) 8 BITS character format : 8 (BITPIX ) Tables are 2-d character array : 2 (NAXIS ) Characters in a row : 80 (NAXIS1 ) Number of rows in a table : 1 (NAXIS2 ) Parameter count always 0 : 0 (PCOUNT ) Group count always 1 : 1 (GCOUNT ) No of columns in table : 20 (TFIELDS ) : '1J ' (TFORM1 ) Filter ID (CHW3 position) : 'PPAPFILT' (TTYPE1 ) : '1J ' (TFORM2 ) Aperture ID (CHW2 position) : 'PPAPAPER' (TTYPE2 ) : '1J ' (TFORM3 ) Number of background reference positions : 'PPAPNBCK' (TTYPE3 ) : '1E ' (TFORM4 ) Source flux : 'PPAPSRCE' (TTYPE4 ) : 'Jy ' (TUNIT4 ) : '1E ' (TFORM5 ) Uncertainty in source flux : 'PPAPSRCU' (TTYPE5 ) : 'Jy ' (TUNIT5 ) : '1E ' (TFORM6 ) Source surface brightness : 'PPAPSRCB' (TTYPE6 ) : 'MJy/sr ' (TUNIT6 ) : '1E ' (TFORM7 ) Uncertainty in source surface brightness : 'PPAPSCBU' (TTYPE7 ) : 'MJy/sr ' (TUNIT7 ) : '1E ' (TFORM8 ) Background for given aperture : 'PPAPBACK' (TTYPE8 ) : 'Jy ' (TUNIT8 ) : '1E ' (TFORM9 ) Uncertainty in background : 'PPAPBCKU' (TTYPE9 ) : 'Jy ' (TUNIT9 ) : '1E ' (TFORM10 ) Source plus background : 'PPAPSPB ' (TTYPE10 ) : 'Jy ' (TUNIT10 ) : '1E ' (TFORM11 ) Uncertainty in source plus background : 'PPAPSPBU' (TTYPE11 ) : 'Jy ' (TUNIT11 ) : '1E ' (TFORM12 ) Source plus background (brightness) : 'PPAPSBB ' (TTYPE12 ) : 'MJy/sr ' (TUNIT12 ) : '1E ' (TFORM13 ) Uncertainty in source plus background (brightn: 'PPAPSBBU' (TTYPE13 ) : 'MJy/sr ' (TUNIT13 ) : '1E ' (TFORM14 ) Background at reference position 1 : 'PPAPBCK1' (TTYPE14 ) : 'Jy ' (TUNIT14 ) : '1E ' (TFORM15 ) Uncertainty in background 1 : 'PPAPBK1U' (TTYPE15 ) : 'Jy ' (TUNIT15 ) : '1E ' (TFORM16 ) Background at reference position 2 : 'PPAPBCK2' (TTYPE16 ) : 'Jy ' (TUNIT16 ) : '1E ' (TFORM17 ) Uncertainty in background 2 : 'PPAPBK2U' (TTYPE17 ) : 'Jy ' (TUNIT17 ) : '1E ' (TFORM18 ) Mean background intensity : 'PPAPBINT' (TTYPE18 ) : 'MJy/ster' (TUNIT18 ) : '1E ' (TFORM19 ) Uncertainty in background intensity : 'PPAPBINU' (TTYPE19 ) : 'MJy/ster' (TUNIT19 ) : '1J ' (TFORM20 ) Number of accepted chopper cycles : 'PPAPNCYC' (TTYPE20 ) COMMENT ******************************************************** COMMENT !!!WARNING!!! COMMENT The DEFAULT responsivity has been used in the processing. COMMENT ********************************************************* User specified parameters per filter/aperture configuration: -------------------------------------------------------------- Filter/aperture configuration No.1: =================================== Filter : 'P2_25_UM' (FILTER1 ) Central Wavelength of filter (m) : 2.50000E-05 (LAMBDA1 ) Expected source flux (Jy) : 5.80003E+00 (EXFLUX1 ) Uncertainty in expected flux (Jy) : 5.80003E+00 (UNCFLX1 ) Max expected background (MJy/ster) : 3.69999E+01 (MXBACK1 ) Aperture : '52" = 2.3mm' (APER1 ) Flux density (source) (Jy) : 6.70837E+00 (SOURCE1 ) Uncertainty in flux (source)(Jy) : 1.96585E+00 (SOURCU1 ) Flux density (source + background) (Jy) : 9.67763E+00 (SBACK1 ) Uncertainty in flux (source + background)(Jy) : 1.86946E+00 (SBACKU1 ) Measurements per filter/aperture configuration: ----------------------------------------------- Filter/aperture configuration No.1: =================================== Filter : 'P2_25_UM' (FILTER1 ) Aperture : '52" = 2.3mm' (APER1 ) Measured background (MJy/ster) : 5.59831E+01 (BACK1 ) Number of background reference positions = 1 (PPAPNBCK) Source flux = 6.7084 (PPAPSRCE) Uncertainty in source flux = 1.9658 (PPAPSRCU) Source surface brightness = 2.9693 (PPAPSRCB) Uncertainty in source surface brightness = 0.6080 (PPAPSCBU) Background for given aperture = 9.6776 (PPAPBACK) Uncertainty in background = 1.8695 (PPAPBCKU) Source plus background = 2.9693 (PPAPSPB ) Uncertainty in source plus background = 0.6080 (PPAPSPBU) Source plus background (brightness) = 0.0000 (PPAPSBB ) Uncertainty in source plus background (brightn= 0.0000 (PPAPSBBU) Background at reference position 1 = 55.9831 (PPAPBCK1) Uncertainty in background 1 = 11.4634 (PPAPBK1U)
The meaning of the keywords in the FITS file is provided in Chapter 13. We see that the auto analysis product contains information of a triangular chopped measurement in the 25 m filter using the aperture. The flux of Altair as determined by OLP10 is Jy, not colour corrected. The measurement time is not given, this information is stored in the PSTA product. Note that the measurement time can be found in the IDA, under source `Details' in either the `Latest Results' or `Shopping Basket' screen.
Another utility which can be used for such a purpose is the routine in FTOOLS. For more information on FTOOLS see:
http://heasarc.gsfc.nasa.gov/ Software FTOOLS
Any image processing or displaying system should be able to display the AA FITS image files (PGAI, PGAU, PGAT). A frequently used tool for such purposes is SAOimage, available at:
http://tdc-www.harvard.edu/ SAOimage