XLCALMASTR ivo://nasa.heasarc/xlcalmastr NASA/GSFC HEASARC HEASARC 2026-07-17 NASA/GSFC HEASARC help desk heasarc-vo at athena.gsfc.nasa.gov Observation This database table records high-level information for the observations obtained with the XL-Calibur experiment. The XL-Calibur is a balloon-borne second-generation (X-ray-focusing) Compton polarimeter operational in the energy range ~15-80 keV with the main objective to measure polarization in hard X-rays for a selection of bright sources. XL-Calibur was successfully launched from the Esrange Space Center (Kiruna, Sweden) on July 9th, 2024 and following circumpolar winds in the west direction, the payload landed with a parachute near Kugluktuk (Canada) on July 14th. During operation, the Crab system (pulsar and wind nebula) and Cygnus X-1 black (X-ray binary system) were successfully observed. The data from these two sources were divided in observations roughly one day long. An observation is defined as a collection of snap-shots where data are acquired on one specific on-source position alternate to an off-source position. The off source position data are used as background data. Each observation is labeled with a sequence number. The data associated includes event files for the on-source and off-source positions and three on-source spectra derived for the Stokes parameters I, Q, U, and an equivalent set for the off-source position. This database table contains one record for each sequence number and includes parameters related to the observation. The contents of this database table are generated at the HEASARC using information from the data files. The table was last updated in August 2025. This is a service provided by NASA HEASARC . 2025MNRAS.540L..34A https://heasarc.gsfc.nasa.gov/W3Browse/all/xlcalmastr.html Archive Research served-by HEASARC TAP https://heasarc.gsfc.nasa.gov/xamin/vo/cone?showoffsets&table=xlcalmastr& GET text/xml 180 99999 true 83.6331 22.0145 0.25 https://heasarc.gsfc.nasa.gov/xamin/vo/tap https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/getvotable.pl?name=xlcalmastr GET text/xml https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/w3query.pl?tablehead=name=heasarc_xlcalmastr&Action=More+Options&Action=Parameter+Search&ConeAdd=1 XL-CALIBUR 0.25 X-ray public xlcalmastr XL-Calibur Master Catalog obsid Unique Observation/Sequence Number (YYYYZZSSSS) meta.id;obs char nullable name Source Designation meta.id;meta.main char nullable ra Right Ascension of the Source degree pos.eq.ra;meta.main double nullable dec Declination of the Source degree pos.eq.dec;meta.main double nullable "time" Start Time of the Observation mjd time.start;obs double nullable exposure_on_src Total Time on Source s time.duration;obs.exposure;src double nullable bii Galactic Latitude of the Source degree pos.galactic.lat double nullable end_time Stop Time of the Observation mjd time.end;obs double nullable num_snapshot_off_src Number of Time Intervals off Source meta.number int nullable processing_version Processing Version meta.version char nullable lii Galactic Longitude of the Source degree pos.galactic.lon double nullable exposure_off_src Total Time off Source s time.duration;obs.exposure double nullable processing_date Date/Time of Data Processing mjd time.processing double nullable num_snapshot_on_src Number of Time Intervals on Source meta.number 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