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Last modified: 8 August 2018

Per-Observation Detections Table


Each identified distinct X-ray source on the sky is represented in the catalog by one or more "source observation" entries - one for each observation in which the source has been detected - and a single "master source" entry. The individual source entries record all of the properties about a detection extracted from a single observation, as well as associated file-based data products, which are observation-specific.

Note: Source properties in the catalog which have a value for each science energy band (type "double[6]", "long[6]", and "integer[6]" in the table below) have the corresponding letters appended to their names. For example, "flux_aper_b" and "flux_aper_h" represent the background-subtracted, aperture-corrected broad-band and hard-band energy fluxes, respectively.

Go to: Catalog Columns Index | Alphabetical List
Context Column Name Type Units Description
Observation Identification obsid integer observation identifier (ObsID)
obi integer Observation Interval number (ObI)

Pointing Information targname string target name for the observation
ra_targ double deg target position specified by observer, ICRS right ascension
dec_targ double deg target position specified by observer, ICRS declination
ra_pnt double deg mean spacecraft pointing during the observation, ICRS right ascension
dec_pnt double deg mean spacecraft pointing during the observation, ICRS declination
roll_pnt double deg mean spacecraft roll angle during the observation
chipx_pnt double pixel detector (chip coordinates) Cartesian x position corresponding to (ra_pnt, dec_pnt)
chipy_pnt double pixel detector (chip coordinates) Cartesian y position corresponding to (ra_pnt, dec_pnt)
chip_id_pnt integer detector (chip coordinates) identifier used to define (chipx_pnt, chipy_pnt)
ra_nom double deg observation tangent plane reference position, ICRS right ascension
dec_nom double deg observation tangent plane reference position, ICRS declination
roll_nom double deg observation tangent plane roll angle (used to determine tangent plane North)

Timing Information gti_start double s start time for the valid observation data in mission elapsed time (MET: seconds since 1998 Jan 01 00:00:00 TT)
gti_stop double s stop time for the valid observation data in mission elapsed time (MET: seconds since 1998 Jan 01 00:00:00 TT)
gti_elapse double s total elapsed time of the observation (gti_stop - gti_start)
gti_obs string (TT) start time of valid observation data (TT), ISO 8601 format (yyyy-mm-ddThh:mm:ss)
gti_end string (TT) stop time of valid observation data (TT), ISO 8601 format (yyyy-mm-ddThh:mm:ss)
gti_mjd_obs double MJD (TT) modified Julian date for the start time of the valid observation data (TT)
mjd_ref double MJD (TT) modified Julian date reference corresponding to zero seconds mission elapsed time

Observing Cycle ao integer Chandra observing cycle in which the observation was scheduled

Instrument Configuration instrument string instrument used for the observation: 'ACIS' or 'HRC'
grating string transmission grating used for the observation: 'NONE', 'HETG', or 'LETG'
datamode string instrument data mode used for the observation
readmode string ACIS readout mode used for the observation: 'TIMED' or 'CONTINUOUS'
cycle string ACIS readout cycle for alternating exposure (interleaved) mode observations: P (primary) or S (secondary). Value is P for all other ACIS modes.
exptime double ACIS CCD frame time
timing_mode boolean HRC precision timing mode

Aspect Information sim_x double mm SIM focus stage position during observation
sim_z double mm SIM translation stage position during observation
dy double mm mean aspect dy offset during observation
dz double mm mean aspect dz offset during observation
dtheta double deg mean aspect dtheta during observation
deltax double arcsec SKY coordinate system X translation correction required to co-align observation astrometric frame within observation stack
deltay double arcsec SKY coordinate system Y translation correction required to co-align observation astrometric frame within observation stack
deltarot double deg SKY coordinate system roll angle correction required to co-align observation astrometric frame within observation stack
dscale double deg SKY coordinate system scale factor correction required to co-align observation astrometric frame within observation stack
man_astrom_flag boolean SKY coordinate system scale factor correction required to co-align observation astrometric frame within observation stack

Processing Information ascdsver string software version used to create the Level 3 observation event data file
caldbver string calibration database version used to calibrate the Level 3 observation event data file
crdate string creation date and time of the Level 3 event file, UTC

Source Identification region_id integer detection region identifier (component number)

Position and Position Errors theta double arcmin PSF 90% ECF aperture off-axis angle, θ
phi double deg PSF 90% ECF aperture azimuthal angle, φ
chipx double pixel detector (chip coordinates) Cartesian x position corresponding to (theta, phi) (θ, φ)
chipy double pixel detector (chip coordinates) Cartesian y position corresponding to (θ, φ)
chip_id integer detector (chip coordinates) identifier used to define (chipx, chipy)

Source Significance flux_significance double[6] significance of the single-observation detection determined from the ratio of the single-observation detection flux to the estimated error in the local background for each source detection energy band
likelihood double[6] significance of the single-observation detection computed by the single-observation detection algorithm for each source detection energy band

Source Flags conf_code integer compact detection may be confused (bit encoded: 1: background region overlaps another background region; 2: background region overlaps another source region; 4: source region overlaps another background region; 8: source region overlaps another source region; 256: compact detection is overlaid on an extended detection)
dither_warning_flag boolean highest statistically significant peak in the power spectrum of the detection source region count rate occurs at the dither frequency or at a beat frequency of the dither frequency of the observation
edge_code coded byte detection position, or source or background region dithered off a detector boundary (chip pixel mask) during the observation (bit encoded: 1: background region dithers off detector boundary; 2:source region dithers off detector boundary; 4: detection position dithers off detector boundary)
extent_code integer[6] detection is extended, or deconvolved compact detection extent is inconsistent with a point source at the 90% confidence level in one or more energy bands (bit encoded: 1, 2, 4, 8, 16, 32: deconvolved compact detection extent is not consistent with a point source in each science energy band
multi_chip_code byte source position, or source or background region dithered multiple detector chips during the observation (bit encoded: 1: background region dithers across 2 chips; 2: background region dithers across >2 chips; 4: source region dithers across 2 chips; 8: source region dithers across >2 chips; 16: detection position dithers across 2 chips; 32: detection position dithers across >2 chips)
pileup_warning double counts/frame/pixel ACIS pile-up fraction estimated from the coiunt rate of the brightest 3x3 pixel island
sat_src_flag boolean detection is saturated; detection properties are unreliable
streak_src_flag boolean detection is located on an ACIS readout streak; detection properties may be affected
var_code byte detection displays flux variability in one or more energy bands (bit encoded: 1,2,4,8,16,32: intra-observation variability detected in each science energy band

Source Extent and Errors mjr_axis_raw double[6] arcsec 1σ radius along the major axis of the ellipse defining the observed detection extent of a source for each science energy band
mjr_axis_raw_lolim double[6] arcsec 1σ radius along the major axis of the ellipse defining the observed detection extent (68% lower confidence limit) for each science energy band
mjr_axis_raw_hilim double[6] arcsec 1σ radius along the major axis of the ellipse defining the observed detection extent (68% upper confidence limit) for each science energy band
mnr_axis_raw double[6] arcsec 1σ radius along the minor axis of the ellipse defining the observed detection extent for each science energy band
mnr_axis_raw_lolim double[6] arcsec 1σ radius along the minor axis of the ellipse defining the observed detection extent (68% lower confidence limit) for each science energy band
mnr_axis_raw_hilim double[6] arcsec 1σ radius along the minor axis of the ellipse defining the observed detection extent (68% upper confidence limit) for each science energy band
pos_angle_raw double[6] deg position angle of the major axis of the ellipse defining the observed detection extent for each science energy band
pos_angle_raw_lolim double[6] deg position angle of the major axis of the ellipse defining the observed detection extent (68% lower confidence limit) for each science energy band
pos_angle_raw_hilim double[6] deg position angle of the major axis of the ellipse defining the observed detection extent (68% upper confidence limit) for each science energy band
psf_mjr_axis_raw double[6] arcsec 1σ radius along the major axis of the ellipse defining the local PSF extent for each science energy band
psf_mjr_axis_raw_lolim double[6] arcsec 1σ radius along the major axis of the ellipse defining the local PSF extent (68% lower confidence limit) for each science energy band
psf_mjr_axis_raw_hilim double[6] arcsec 1σ radius along the major axis of the ellipse defining the local PSF extent (68% upper confidence limit) for each science energy band
psf_mnr_axis_raw double[6] arcsec 1σ radius along the minor axis of the ellipse defining the local PSF extent for each science energy band
psf_mnr_axis_raw_lolim double[6] arcsec 1σ radius along the minor axis of the ellipse defining the local PSF extent (68% lower confidence limit) for each science energy band
psf_mnr_axis_raw_hilim double[6] arcsec 1σ radius along the minor axis of the ellipse defining the local PSF extent (68% upper confidence limit) for each science energy band
psf_pos_angle_raw double[6] deg position angle of the major axis of the ellipse defining the local PSF extent for each science energy band
psf_pos_angle_raw_lolim double[6] deg position angle of the major axis of the ellipse defining the local PSF extent (68% lower confidence limit) for each science energy band
psf_pos_angle_raw_hilim double[6] deg position angle of the major axis of the ellipse defining the local PSF extent (68% upper confidence limit) for each science energy band
major_axis double[6] arcsec 1σ radius along the major axis of the ellipse defining the deconvolved detection extent for each science energy band
major_axis_lolim double[6] arcsec 1σ radius along the major axis of the ellipse defining the deconvolved detection extent (68% lower confidence limit) for each science energy band
major_axis_hilim double[6] arcsec 1σ radius along the major axis of the ellipse defining the deconvolved detection extent (68% upper confidence limit) for each science energy band
minor_axis double[6] arcsec 1σ radius along the minor axis of the ellipse defining the deconvolved detection extent for each science energy band
minor_axis_lolim double[6] arcsec 1σ radius along the minor axis of the ellipse defining the deconvolved detection extent (68% lower confidence limit) for each science energy band
minor_axis_hilim[6] double arcsec 1σ radius along the minor axis of the ellipse defining the deconvolved detection extent (68% upper confidence limit) for each science energy band
pos_angle double[6] deg position angle (referenced from local true north) of the major axis of the ellipse defining the deconvolved detection extent for each science energy band
pos_angle_lolim double[6] deg position angle (referenced from local true north) of the major axis of the ellipse defining the deconvolved detection extent (68% lower confidence limit) for each science energy band
pos_angle_hilim double[6] deg position angle (referenced from local true north) of the major axis of the ellipse defining the deconvolved detection extent (68% upper confidence limit) for each science energy band
src_area double[6] sq. arcseconds area of the deconvolved detection extent ellipse, or area of the detection polygon for extended detections for each science energy band

Aperture Photometry cnts_aper long[6] counts total counts measured in the modified source region for each science energy band
cnts_aperbkg long[6] counts total counts measured in the modified background region for each science energy band
src_cnts_aper double[6] counts aperture-corrected detection net counts inferred from the source region aperture for each science energy band
src_cnts_aper_lolim double[6] counts aperture-corrected detection net counts inferred from the source region aperture (68% lower confidence limit) for each science energy band
src_cnts_aper_hilim double[6] counts aperture-corrected detection net counts inferred from the source region aperture (68% upper confidence limit) for each science energy band
src_rate_aper double[6] counts s-1 aperture-corrected detection net count rate inferred from the source region aperture for each science energy band
src_rate_aper_lolim double[6] counts s-1 aperture-corrected detection net count rate inferred from the source region aperture (68% lower confidence limit) for each science energy band
src_rate_aper_hilim double[6] counts s-1 aperture-corrected detection net count rate inferred from the source region aperture (68% upper confidence limit) for each science energy band
photflux_aper double[6] photons s-1 cm-2 aperture-corrected detection net photon flux inferred from the source region aperture, calculated by counting X-ray events for each science energy band
photflux_aper_lolim double[6] photons s-1 cm-2 aperture-corrected detection net photon flux inferred from the source region aperture, calculated by counting X-ray events (68% lower confidence limit) for each science energy band
photflux_aper_hilim double[6] photons s-1 cm-2 aperture-corrected detection net photon flux inferred from the source region aperture, calculated by counting X-ray events (68% upper confidence limit) for each science energy band
flux_aper double[6] ergs s-1 cm-2 aperture-corrected detection net energy flux inferred from the source region aperture, calculated by counting X-ray events for each science energy band
flux_aper_lolim double[6] ergs s-1 cm-2 aperture-corrected detection net energy flux inferred from the source region aperture, calculated by counting X-ray events (68% lower confidence limit) for each science energy band
flux_aper_hilim double[6] ergs s-1 cm-2 aperture-corrected detection net energy flux inferred from the source region aperture, calculated by counting X-ray events (68% upper confidence limit) for each science energy band
cnts_aper90 long[6] counts total counts observed in the modified PSF 90% ECF aperture for each science energy band
cnts_aper90bkg long[6] counts total counts observed in the modified PSF 90% ECF background aperture for each science energy band
src_cnts_aper90 double[6] counts aperture-corrected detection net counts inferred from the PSF 90% ECF aperture for each science energy band
src_cnts_aper90_lolim double[6] counts aperture-corrected detection net counts inferred from the PSF 90% ECF aperture (68% lower confidence limit) for each science energy band
src_cnts_aper90_hilim double[6] counts aperture-corrected detection net counts inferred from the PSF 90% ECF aperture (68% upper confidence limit) for each science energy band
src_rate_aper90 double[6] counts s-1 aperture-corrected detection net count rate inferred from the PSF 90% ECF aperture for each science energy band
src_rate_aper90_lolim double[6] counts s-1 aperture-corrected detection net count rate inferred from the PSF 90% ECF aperture (68% lower confidence limit) for each science energy band
src_rate_aper90_hilim double[6] counts s-1 aperture-corrected detection net count rate inferred from the PSF 90% ECF aperture (68% upper confidence limit) for each science energy band
photflux_aper90 double[6] photons s-1 cm-2 aperture-corrected detection net photon flux inferred from the PSF 90% ECF aperture, calculated by counting X-ray events for each science energy band
photflux_aper90_lolim double[6] photons s-1 cm-2 aperture-corrected detection net photon flux inferred from the PSF 90% ECF aperture, calculated by counting X-ray events (68% lower confidence limit) for each science energy band
photflux_aper90_hilim double[6] photons s-1 cm-2 aperture-corrected detection net photon flux inferred from the PSF 90% ECF aperture, calculated by counting X-ray events (68% upper confidence limit) for each science energy band
flux_aper90 double[6] ergs s-1 cm-2 aperture-corrected detection net energy flux inferred from the PSF 90% ECF aperture, calculated by counting X-ray events for each science energy band
flux_aper90_lolim double[6] ergs s-1 cm-2 aperture-corrected detection net energy flux inferred from the PSF 90% ECF aperture, calculated by counting X-ray events (68% lower confidence limit) for each science energy band
flux_aper90_hilim double[6] ergs s-1 cm-2 aperture-corrected detection net energy flux inferred from the PSF 90% ECF aperture, calculated by counting X-ray events (68% upper confidence limit) for each science energy band
ra_aper90 double[6] deg center of the PSF 90% ECF and PSF 90% ECF background apertures, ICRS right ascension for each science energy band
dec_aper90 double[6] deg center of the PSF 90% ECF and PSF 90% ECF background apertures, ICRS declination for each science energy band
mjr_axis_aper90 double[6] arcsec semi-major axis of the elliptical PSF 90% ECF aperture for each science energy band
mnr_axis_aper90 double[6] arcsec semi-minor axis of the elliptical PSF 90% ECF aperture for each science energy band
pos_angle_aper90 double[6] deg position angle (referenced from local true north) of the semi-major axis of the elliptical PSF 90% ECF aperture for each science energy band
mjr_axis1_aper90bkg double[6] arcsec semi-major axis of the inner ellipse of the annular PSF 90% ECF background aperture for each science energy band
mnr_axis1_aper90bkg double[6] arcsec semi-minor axis of the inner ellipse of the annular PSF 90% ECF background aperture for each science energy band
mjr_axis2_aper90bkg double[6] arcsec semi-major axis of the outer ellipse of the annular PSF 90% ECF background aperture for each science energy band
mnr_axis2_aper90bkg double[6] arcsec semi-minor axis of the outer ellipse of the annular PSF 90% ECF background aperture for each science energy band
pos_angle_aper90bkg double[6] deg position angle (referenced from local true north) of the semi-major axes of the annular PSF 90% ECF background aperture for each science energy band
area_aper double sq. arcsec area of the modified elliptical source region aperture (includes corrections for exclusion regions due to overlapping detections)
area_aperbkg double sq. arcseconds area of the modified annular background region aperture (includes corrections for exclusion regions due to overlapping detections)
area_aper90 double[6] sq. arcseconds area of the modified elliptical PSF 90% ECF aperture (includes corrections for exclusion regions due to overlapping detections) for each science energy band
area_aper90bkg double[6] sq. arcseconds area of the modified annular PSF 90% ECF background aperture (includes corrections for exclusion regions due to overlapping detections for each science energy band
psf_frac_aper double[6] fraction of the PSF included in the modified elliptical source region aperture for each science energy band
psf_frac_aperbkg double[6] fraction of the PSF included in the modified annular background region aperture for each science energy band
psf_frac_aper90 double[6] fraction of the PSF included in the modified elliptical PSF 90% ECF aperture for each science energy band
psf_frac_aper90bkg double[6] fraction of the PSF included in the modified annular PSF 90% ECF background aperture for each science energy band
phot_nsrcs integer[6] number of detections fit simultaneously to compute aperture photometry quantities

Model Energy Fluxes flux_powlaw_aper double[6] ergs s-1 cm-2 source region aperture model energy flux inferred from the canonical absorbed power-law model [NH = NH(Gal); γ = 2.0] for each science energy band
flux_powlaw_aper_lolim double[6] ergs s-1 cm-2 source region aperture model energy flux inferred from the canonical absorbed power-law model [NH = NH(Gal); γ = 2.0] (68% lower confidence limit) for each science energy band
flux_powlaw_aper_hilim double[6] ergs s-1 cm-2 source region aperture model energy flux inferred from the canonical absorbed power-law model [NH = NH(Gal); γ = 2.0] (68% upper confidence limit) for each science energy band
flux_bb_aper double[6] ergs s-1 cm-2 source region aperture model energy flux inferred from the canonical absorbed black body model [NH = NH(Gal); kT = 0.75 keV] for each science energy band
flux_bb_aper_lolim double[6] ergs s-1 cm-2 source region aperture model energy flux inferred from the canonical absorbed black body model [NH = NH(Gal); kT = 0.75 keV] (68% lower confidence limit) for each science energy band
flux_bb_aper_hilim double[6] ergs s-1 cm-2 source region aperture model energy flux inferred from the canonical absorbed black body model [NH = NH(Gal); kT = 0.75 keV] (68% upper confidence limit) for each science energy band
flux_brems_aper double[6] ergs s-1 cm-2 source region aperture model energy flux inferred from the canonical absorbed bremsstrahlung model [NH = NH(Gal); kT = 3.5 keV] for each science energy band
flux_brems_aper_lolim double[6] ergs s-1 cm-2 source region aperture model energy flux inferred from the canonical absorbed bremsstrahlung model [NH = NH(Gal); kT = 3.5 keV] (68% lower confidence limit) for each science energy band
flux_brems_aper_hilim double[6] ergs s-1 cm-2 source region aperture model energy flux inferred from the canonical absorbed bremsstrahlung model [NH = NH(Gal); kT = 3.5 keV] (68% upper confidence limit) for each science energy band
flux_apec_aper double[6] ergs s-1 cm-2 source region aperture model energy flux inferred from the canonical absorbed APEC model [NH = NH(Gal); kT = 6.5 keV] for each science energy band
flux_apec_aper_lolim double[6] ergs s-1 cm-2 source region aperture model energy flux inferred from the canonical absorbed APEC model [NH = NH(Gal); kT = 6.5 keV] (68% lower confidence limit) for each science energy band
flux_apec_aper_hilim double[6] ergs s-1 cm-2 source region aperture model energy flux inferred from the canonical absorbed APEC model [NH = NH(Gal); kT = 6.5 keV] (68% upper confidence limit) for each science energy band
flux_powlaw_aper90 double[6] ergs s-1 cm-2 PSF 90% ECF aperture model energy flux inferred from the canonical absorbed power-law model [NH = NH(Gal); γ = 2.0] for each science energy band
flux_powlaw_aper90_lolim double[6] ergs s-1 cm-2 PSF 90% ECF aperture model energy flux inferred from the canonical absorbed power-law model [NH = NH(Gal); γ = 2.0] (68% lower confidence limit) for each science energy band
flux_powlaw_aper90_hilim double[6] ergs s-1 cm-2 PSF 90% ECF aperture model energy flux inferred from the canonical absorbed power-law model [NH = NH(Gal); γ = 2.0] (68% upper confidence limit) for each science energy band
flux_bb_aper90 double[6] ergs s-1 cm-2 PSF 90% ECF aperture model energy flux inferred from the canonical absorbed black body model [NH = NH(Gal); kT = 0.75 keV] for each science energy band
flux_bb_aper90_lolim double[6] ergs s-1 cm-2 PSF 90% ECF aperture model energy flux inferred from the canonical absorbed black body model [NH = NH(Gal); kT = 0.75 keV] (68% lower confidence limit) for each science energy band
flux_bb_aper90_hilim double[6] ergs s-1 cm-2 PSF 90% ECF aperture model energy flux inferred from the canonical absorbed black body model [NH = NH(Gal); kT = 0.75 keV] (68% upper confidence limit) for each science energy band
flux_brems_aper90 double[6] ergs s-1 cm-2 PSF 90% ECF aperture model energy flux inferred from the canonical absorbed bremsstrahlung model [NH = NH(Gal); kT = 3.5 keV] for each science energy band
flux_brems_aper90_lolim double[6] ergs s-1 cm-2 PSF 90% ECF aperture model energy flux inferred from the canonical absorbed bremsstrahlung model [NH = NH(Gal); kT = 3.5 keV] (68% lower confidence limit) for each science energy band
flux_brems_aper90_hilim double[6] ergs s-1 cm-2 PSF 90% ECF aperture model energy flux inferred from the canonical absorbed bremsstrahlung model [NH = NH(Gal); kT = 3.5 keV] (68% upper confidence limit) for each science energy band
flux_apec_aper90 double[6] ergs s-1 cm-2 PSF 90% ECF aperture model energy flux inferred from the canonical absorbed APEC model [NH = NH(Gal); kT = 6.5 keV] for each science energy band
flux_apec_aper90_lolim double[6] ergs s-1 cm-2 PSF 90% ECF aperture model energy flux inferred from the canonical absorbed APEC model [NH = NH(Gal); kT = 6.5 keV] (68% lower confidence limit) for each science energy band
flux_apec_aper90_hilim double[6] ergs s-1 cm-2 PSF 90% ECF aperture model energy flux inferred from the canonical absorbed APEC model [NH = NH(Gal); kT = 6.5 keV] (68% upper confidence limit) for each science energy band

Hardness Ratios hard_hm double ACIS hard (2.0-7.0 keV) - medium (1.2-2.0 keV) energy band hardness ratio
hard_hm_lolim double ACIS hard (2.0-7.0 keV) - medium (1.2-2.0 keV) energy band hardness ratio (68% lower confidence limit)
hard_hm_hilim double ACIS hard (2.0-7.0 keV) - medium (1.2-2.0 keV) energy band hardness ratio (68% upper confidence limit)
hard_hs double ACIS hard (2.0-7.0 keV) - soft (0.5-1.2 keV) energy band hardness ratio
hard_hs_lolim double ACIS hard (2.0-7.0 keV) - soft (0.5-1.2 keV) energy band hardness ratio (68% lower confidence limit)
hard_hs_hilim double ACIS hard (2.0-7.0 keV) - soft (0.5-1.2 keV) energy band hardness ratio (68% upper confidence limit)
hard_ms double ACIS medium (1.2-2.0 keV) - soft (0.5-1.2 keV) energy band hardness ratio
hard_ms_lolim double ACIS medium (1.2-2.0 keV) - soft (0.5-1.2 keV) energy band hardness ratio (68% lower confidence limit)
hard_ms_hilim double ACIS medium (1.2-2.0 keV) - soft (0.5-1.2 keV) energy band hardness ratio (68% upper confidence limit)

Spectral Properties flux_powlaw double ergs s-1 cm-2 net integrated 0.5-7.0 keV energy flux of the best fitting absorbed power-law model spectrum to the source region aperture PI spectrum
flux_powlaw_lolim double ergs s-1 cm-2 net integrated 0.5-7.0 keV energy flux of the best fitting absorbed power-law model spectrum to the source region aperture PI spectrum (68% lower confidence limit)
flux_powlaw_hilim double ergs s-1 cm-2 net integrated 0.5-7.0 keV energy flux of the best fitting absorbed power-law model spectrum to the source region aperture PI spectrum (68% upper confidence limit)
powlaw_gamma double photon index, defined as FE ∝ E, of the best fitting absorbed power-law model spectrum to the source region aperture PI spectrum
powlaw_gamma_lolim double photon index, defined as FE ∝ E, of the best fitting absorbed power-law model spectrum to the source region aperture PI spectrum (68% lower confidence limit)
powlaw_gamma_hilim double photon index, defined as FE ∝ E, of the best fitting absorbed power-law model spectrum to the source region aperture PI spectrum (68% upper confidence limit)
powlaw_gamma_rhat double photon index convergence criterion of the best fitting absorbed power-law model spectrum to the source region aperture PI spectrum
powlaw_nh double HI atoms 1020 cm-2 NH column density of the best fitting absorbed power-law model spectrum to the source region aperture PI spectrum
powlaw_nh_lolim double HI atoms 1020 cm-2 NH column density of the best fitting absorbed power-law model spectrum to the source region aperture PI spectrum (68% lower confidence limit)
powlaw_nh_hilim double HI atoms 1020 cm-2 NH column density of the best fitting absorbed power-law model spectrum to the source region aperture PI spectrum (68% upper confidence limit)
powlaw_nh_rhat double NH column density convergence criterion of the best fitting absorbed power-law model spectrum to the source region aperture PI spectrum
powlaw_ampl double amplitude of the best fitting absorbed power-law model spectrum to the source region aperture PI spectrum
powlaw_ampl_lolim double amplitude of the best fitting absorbed power-law model spectrum to the source region aperture PI spectrum (68% lower confidence limit)
powlaw_ampl_hilim double amplitude of the best fitting absorbed power-law model spectrum to the source region aperture PI spectrum (68% upper confidence limit)
powlaw_ampl_rhat double amplitude convergence criterion of the best fitting absorbed power-law model spectrum to the source region aperture PI spectrum
powlaw_stat double χ2 statistic per degree of freedom of the best fitting absorbed power-law model spectrum to the source region aperture PI spectrum
flux_bb double ergs s-1 cm-2 net integrated 0.5-7.0 keV energy flux of the best fitting absorbed black body model spectrum to the source region aperture PI spectrum
flux_bb_lolim double ergs s-1 cm-2 net integrated 0.5-7.0 keV energy flux of the best fitting absorbed black body model spectrum to the source region aperture PI spectrum (68% lower confidence limit)
flux_bb_hilim double ergs s-1 cm-2 net integrated 0.5-7.0 keV energy flux of the best fitting absorbed black body model spectrum to the source region aperture PI spectrum (68% upper confidence limit)
bb_kt double keV temperature (kT) of the best fitting absorbed black body model spectrum to the source region aperture PI spectrum
bb_kt_lolim double keV temperature (kT) of the best fitting absorbed black body model spectrum to the source region aperture PI spectrum (68% lower confidence limit)
bb_kt_hilim double keV temperature (kT) of the best fitting absorbed black body model spectrum to the source region aperture PI spectrum (68% upper confidence limit)
bb_kt_rhat double temperature (kT) convergence criterion of the best fitting absorbed black body model spectrum to the source region aperture PI spectrum
bb_nh double HI atoms 1020 cm-2 NH column density of the best fitting absorbed black body model spectrum to the source region aperture PI spectrum
bb_nh_lolim double HI atoms 1020 cm-2 NH column density of the best fitting absorbed black body model spectrum to the source region aperture PI spectrum (68% lower confidence limit)
bb_nh_hilim double HI atoms 1020 cm-2 NH column density of the best fitting absorbed black body model spectrum to the source region aperture PI spectrum (68% upper confidence limit)
bb_nh_rhat double NH column density convergence criterion of the best fitting absorbed black body model spectrum to the source region aperture PI spectrum
bb_ampl double amplitude of the best fitting absorbed black body model spectrum to the source region aperture PI spectrum
bb_ampl_lolim double amplitude of the best fitting absorbed black body model spectrum to the source region aperture PI spectrum (68% lower confidence limit)
bb_ampl_hilim double amplitude of the best fitting absorbed black body model spectrum to the source region aperture PI spectrum (68% upperer confidence limit)
bb_ampl_rhat double amplitude convergence criterion of the best fitting absorbed black body model spectrum to the source region aperture PI spectrum
bb_stat double χ2 statistic per degree of freedom of the best fitting absorbed black body model spectrum to the source region aperture PI spectrum
flux_brems double ergs s-1 cm-2 net integrated 0.5-7.0 keV energy flux of the best fitting absorbed bremsstrahlung model spectrum to the source region aperture PI spectrum
flux_brems_lolim double ergs s-1 cm-2 net integrated 0.5-7.0 keV energy flux of the best fitting absorbed bremsstrahlung model spectrum to the source region aperture PI spectrum (68% lower confidence limit)
flux_brems_hilim double ergs s-1 cm-2 net integrated 0.5-7.0 keV energy flux of the best fitting absorbed bremsstrahlung model spectrum to the source region aperture PI spectrum (68% upper confidence limit)
brems_kt double keV temperature (kT) of the best fitting absorbed bremsstrahlung model spectrum to the source region aperture PI spectrum
brems_kt_lolim double keV temperature (kT) of the best fitting absorbed bremsstrahlung model spectrum to the source region aperture PI spectrum (68% lower confidence limit)
brems_kt_hilim double keV temperature (kT) of the best fitting absorbed bremsstrahlung model spectrum to the source region aperture PI spectrum (68% upper confidence limit)
brems_kt_rhat double temperature (kT) convergence criterion of the best fitting absorbed bremsstrahlung model spectrum to the source region aperture PI spectrum
brems_nh double HI atoms 1020 cm-2 NH column density of the best fitting absorbed bremsstrahlung model spectrum to the source region aperture PI spectrum
brems_nh_lolim double HI atoms 1020 cm-2 NH column density of the best fitting absorbed bremsstrahlung model spectrum to the source region aperture PI spectrum (68% lower confidence limit)
brems_nh_hilim double HI atoms 1020 cm-2 NH column density of the best fitting absorbed bremsstrahlung model spectrum to the source region aperture PI spectrum (68% upper confidence limit)
brems_nh_rhat double NH column density convergence criterion of the best fitting absorbed bremsstrahlung model spectrum to the source region aperture PI spectrum
brems_norm double amplitude of the best fitting absorbed bremsstrahlung model spectrum to the source region aperture PI spectrum
brems_norm_lolim double amplitude of the best fitting absorbed bremsstrahlung model spectrum to the source region aperture PI spectrum (68% lower confidence limit)
brems_norm_hilim double amplitude of the best fitting absorbed bremsstrahlung model spectrum to the source region aperture PI spectrum (68% upperer confidence limit)
brems_norm_rhat double amplitude convergence criterion of the best fitting absorbed bremsstrahlung model spectrum to the source region aperture PI spectrum
brems_stat double χ2 statistic per degree of freedom of the best fitting absorbed bremsstrahlung model spectrum to the source region aperture PI spectrum
flux_apec double ergs s-1 cm-2 net integrated 0.5-7.0 keV energy flux of the best fitting absorbed APEC model spectrum to the source region aperture PI spectrum
flux_apec_lolim double ergs s-1 cm-2 net integrated 0.5-7.0 keV energy flux of the best fitting absorbed APEC model spectrum to the source region aperture PI spectrum (68% lower confidence limit)
flux_apec_hilim double ergs s-1 cm-2 net integrated 0.5-7.0 keV energy flux of the best fitting absorbed APEC model spectrum to the source region aperture PI spectrum (68% upper confidence limit)
apec_kt double keV temperature (kT) of the best fitting absorbed APEC model spectrum to the source region aperture PI spectrum
apec_kt_lolim double keV temperature (kT) of the best fitting absorbed APEC model spectrum to the source region aperture PI spectrum (68% lower confidence limit)
apec_kt_hilim double keV temperature (kT) of the best fitting absorbed APEC model spectrum to the source region aperture PI spectrum (68% upper confidence limit)
apec_kt_rhat double temperature (kT) convergence criterion of the best fitting absorbed APEC model spectrum to the source region aperture PI spectrum
apec_abund double abundance of the best fitting absorbed APEC model spectrum to the source region aperture PI spectrum
apec_abund_lolim double abundance of the best fitting absorbed APEC model spectrum to the source region aperture PI spectrum (68% lower confidence limit)
apec_abund_hilim double abundance of the best fitting absorbed APEC model spectrum to the source region aperture PI spectrum (68% upper confidence limit)
apec_abund_rhat double abundance convergence criterion of the best fitting absorbed APEC model spectrum to the source region aperture PI spectrum
apec_z double redshift of the best fitting absorbed APEC model spectrum to the source region aperture PI spectrum
apec_z_lolim double redshift of the best fitting absorbed APEC model spectrum to the source region aperture PI spectrum (68% lower confidence limit)
apec_z_hilim double redshift of the best fitting absorbed APEC model spectrum to the source region aperture PI spectrum (68% upper confidence limit)
apec_z_rhat double redshift convergence criterion Redshift of the best fitting absorbed APEC model spectrum to the source region aperture PI spectrum
apec_nh double HI atoms 1020 cm-2 NH column density of the best fitting absorbed APEC model spectrum to the source region aperture PI spectrum
apec_nh_lolim double HI atoms 1020 cm-2 NH column density of the best fitting absorbed APEC model spectrum to the source region aperture PI spectrum (68% lower confidence limit)
apec_nh_hilim double HI atoms 1020 cm-2 NH column density of the best fitting absorbed APEC model spectrum to the source region aperture PI spectrum (68% upper confidence limit)
apec_nh_rhat double NH column density convergence criterion of the best fitting absorbed APEC model spectrum to the source region aperture PI spectrum
apec_norm double amplitude of the best fitting absorbed APEC model spectrum to the source region aperture PI spectrum
apec_norm_lolim double amplitude of the best fitting absorbed APEC model spectrum to the source region aperture PI spectrum (68% lower confidence limit)
apec_norm_hilim double amplitude of the best fitting absorbed APEC model spectrum to the source region aperture PI spectrum (68% upperer confidence limit)
apec_norm_rhat double amplitude convergence criterion of the best fitting absorbed APEC model spectrum to the source region aperture PI spectrum
apec_stat double χ2 statistic per degree of freedom of the best fitting absorbed APEC model spectrum to the source region aperture PI spectrum

Source Variability var_index integer[6] intra-observation Gregory-Loredo variability index in the range [0, 10]: indicates whether the source region photon flux is constant within an observation (highest value across all stacked observations) for each science energy band
var_prob double[6] intra-observation Gregory-Loredo variability probability (highest value across all stacked observations) for each science energy band
ks_prob double[6] intra-observation Kolmogorov-Smirnov test variability probability (highest value across all observations) for each science energy band
kp_prob double[6] intra-observation Kuiper's test variability probability (highest value across all stacked observations) for each science energy band
var_sigma double[6] counts s-1 flux variability standard deviation, calculated from an optimally-binned light curve for each science energy band
var_mean double[6] counts s-1 flux variability mean value, calculated from an optimally-binned light curve for each science energy band
var_min double[6] counts s-1 flux variability minimum value, calculated from an optimally-binned light curve for each science energy band
var_max double[6] counts s-1 flux variability maximum value, calculated from an optimally-binned light curve for each science energy band

Source Timing Information livetime double s effective exposure time for the observation after applying the good time intervals and deadtime correction factor

Source Instrument Information detector string detector elements over which the background region bounding box dithers during the observation: HRC-I, HRC-S, or ACIS-<n>, where <n> is string of the CCD Ids (e.g. "ACIS-78"); see the ACIS focal plane figure in the POG.


Last modified: 8 August 2018
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