TGS ivo://nasa.heasarc/tgs NASA/GSFC HEASARC HEASARC 2026-05-29 NASA/GSFC HEASARC help desk heasarc-vo at athena.gsfc.nasa.gov Spectrum Spectra obtained using the EXOSAT transmission grating spectrometer, TGS. There are two databases TGS and TGS2 as follows: <pre> * TGS - the grating spectra averaged over the positive and negative orders * TGS2 - the postive and negative orders kept separate </pre> TGS provides a better overview of the spectrum, and is quicker to use with a spectral fitting program. This is the default that most users will want to use. Once a user has become more expert and wants to see, for example, if a subtle feature is present in both halves of the grating spectra, the user can access TGS2. This is a service provided by NASA HEASARC . https://heasarc.gsfc.nasa.gov/W3Browse/all/tgs.html Archive Research served-by HEASARC TAP https://heasarc.gsfc.nasa.gov/xamin/vo/cone?showoffsets&table=tgs& GET text/xml 180 99999 true 84.9118442398575 -69.748922380636 0.75 https://heasarc.gsfc.nasa.gov/xamin/vo/tap https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/getvotable.pl?name=tgs GET text/xml https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/w3query.pl?tablehead=name=heasarc_tgs&Action=More+Options&Action=Parameter+Search&ConeAdd=1 EXOSAT 0.75 X-ray public tgs EXOSAT TGS L and R Orders name Source Designation meta.id;meta.main char nullable ra Source Right Ascension degree pos.eq.ra;meta.main double nullable dec Source Declination degree pos.eq.dec;meta.main double nullable instrument Instrument: L1, L2, ME, SSS, etc char nullable exposure_time Detector Exposure Time in seconds s float nullable "time" Start Time of Observation mjd time.start;obs double nullable count_rate Count Rate ct/s phot.count;em.X-ray.soft float nullable filter Instrument Mode: Ar, Xe, fw7 char nullable grating Grating Line Ruling int nullable "__x_ra_dec" System unit vector column double nullable "__y_ra_dec" System unit vector column double nullable "__z_ra_dec" System unit vector column double nullable "__row" System index column char nullable creator Creator (auto, aux) char nullable bii Source Galactic Latitude degree pos.galactic.lat double nullable associated_file_spectrum Name of the Associated Spectrum Files char nullable file_response Name of the Response Files char nullable no_of_bins Number of Time Bins short nullable comments Comments Regarding Width of Mask Used to Extract Grating Spectra from LE Image char nullable pointdec Pointing Declination degree double nullable roll_angle Roll Angle *10 degrees 10^-1_degree short nullable associated_file_backgrou Name of the Associated Background Files char nullable id_number Source Number int nullable process_date Creation Time of Data Files mjd time.processing double nullable duration Duration i.e. stop-start s time.duration;obs float nullable last_update Creation Time of This Entry mjd time.creation double nullable bintime Accumulation Interval for the Lightcurve (seconds) s float nullable pointra Pointing Right Ascension degree double nullable associated_file_response Name of the Associated Response Files char nullable file_bgnd_spectrum Name of the Background Spectral Files char nullable lii Source Galactic Longitude degree pos.galactic.lon double nullable file_lcurve Name of the Rates Files char nullable file_spectrum Name of the Spectral Files char nullable sequence_number Sequence Number of Observation short nullable x_pixels X Pixel of Zero Order short nullable y_pixels Y Pixel of Zero Order short nullable count_rate_error Count Rate Error ct/s stat.error;phot.count;em.X-ray.soft float nullable qflag Quality Flag (ME uses 0=unusable 5=perfect) short nullable