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Last modified: 27 September 2019

Master Sources Table


Each distinct X-ray source identified on the sky is represented in the catalog by a single "master source" entry and one or more "per-stack detection" entries, one for each stack in which the source has been detected and by one or more "per-observation detection" entries, one for each observation contribution to the stack in which the source has been detected. Many of the master source properties are populated from the properties of the Best Block (the one with the largest total exposure) from the Bayesian Block Analysis (e.g., aperture photometry).

Note: Source properties in the catalog which have a value for each science energy band (type "double[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.

Switch to: Columns listed by Context
Column Name Type Units Description
acis_hetg_num integer total number of ACIS/HETG observations contributing to the Master Sources Table record of the source
acis_hetg_time double total livetime for all ACIS/HETG observations contributing to the Master Sources Table record of the source
acis_letg_num integer total number of ACIS/LETG observations contributing to the Master Sources Table record of the source
acis_letg_time double total livetime for all ACIS/LETG observations contributing to the Master Sources Table record of the source
acis_num integer total number of ACIS imaging observations contributing to the Master Sources Table record of the source
acis_time double total livetime for all ACIS imaging observations contributing to the Master Sources Table record of the source
apec_abund double abundance of the best fitting absorbed APEC model spectrum to the source region aperture PI spectrum
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_lolim double abundance of the best fitting absorbed APEC model spectrum to the source region aperture PI spectrum (68% lower 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_kt double keV temperature (kT) of the best fitting absorbed APEC model spectrum to the source region aperture PI spectrum
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_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_rhat double temperature (kT) convergence criterion 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_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_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_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_hilim double amplitude of the best fitting absorbed APEC model spectrum to the source region aperture PI spectrum (68% upperer confidence limit)
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_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
apec_z double redshift of the best fitting absorbed APEC model spectrum to the source region aperture PI spectrum
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_lolim double redshift of the best fitting absorbed APEC model spectrum to the source region aperture PI spectrum (68% lower 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
bb_ampl double amplitude of the best fitting absorbed black body model spectrum to the source region aperture PI spectrum
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_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_rhat double amplitude convergence criterion of the best fitting absorbed black body model spectrum to the source region aperture PI spectrum
bb_kt double keV temperature (kT) of the best fitting absorbed black body model spectrum to the source region aperture PI spectrum
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_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_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_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_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_rhat double NH column density 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
brems_kt double keV temperature (kT) of the best fitting absorbed bremsstrahlung model spectrum to the source region aperture PI spectrum
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_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_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_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_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_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_hilim double amplitude of the best fitting absorbed bremsstrahlung model spectrum to the source region aperture PI spectrum (68% upperer confidence limit)
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_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
conf_flag Boolean source may be confused (source and/or background regions overlap in one or more contributing stacked observations)
dec double deg source position, ICRS declination
dither_warning_flag boolean highest statistically significant peak in the power spectrum of the source region count rate occurs at the dither frequency or at a beat frequency of the dither frequency in one or more observations
err_ellipse_ang double deg position angle (referenced from local true north) of the major axis of the 95% confidence level error ellipse
err_ellipse_r0 double arcseconds major radius of the 95% confidence level position error ellipse
err_ellipse_r1 double arcseconds minor radius of the 95% confidence level position error ellipse
extent_flag Boolean source is extended, or deconvolved source extent is inconsistent with a point source at the 90% confidence level in one or more observations and science energy bands
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_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_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_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)
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)
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_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_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)
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_aper double[6] ergs s-1 cm-2 aperture-corrected net energy flux inferred from the source region aperture, best estimate derived from the longest block of a multi-band, flux-ordered Bayesian Block analysis of the contributing observations, and calculated by counting X-ray events for each science energy band
flux_aper90 double[6] ergs s-1 cm-2 aperture-corrected net energy flux inferred from the PSF 90% ECF aperture, best estimate derived from the longest block of a multi-band, flux-ordered Bayesian Block analysis of the contributing observations, and calculated by counting X-ray events for each science energy band
flux_aper90_avg double[6] ergs s-1 cm-2 aperture-corrected net energy flux inferred from the PSF 90% ECF aperture, averaged over all contributing observations, and calculated by counting X-ray events for each science energy band
flux_aper90_avg_hilim double[6] ergs s-1 cm-2 aperture-corrected net energy flux inferred from the PSF 90% ECF aperture, averaged over all contributing observations, and calculated by counting X-ray events (68% upper confidence limit) for each science energy band
flux_aper90_avg_lolim double[6] ergs s-1 cm-2 aperture-corrected net energy flux inferred from the PSF 90% ECF aperture, averaged over all contributing observations, and 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 net energy flux inferred from the PSF 90% ECF aperture, best estimate derived from the longest block of a multi-band, flux-ordered Bayesian Block analysis of the contributing observations, and calculated by counting X-ray events (68% upper confidence limit) for each science energy band
flux_aper90_lolim double[6] ergs s-1 cm-2 aperture-corrected net energy flux inferred from the PSF 90% ECF aperture, best estimate derived from the longest block of a multi-band, flux-ordered Bayesian Block analysis of the contributing observations, and calculated by counting X-ray events (68% lower confidence limit) for each science energy band
flux_aper_avg double[6] ergs s-1 cm-2 aperture-corrected net energy flux inferred from the source region aperture, averaged over all contributing observations, and calculated by counting X-ray events for each science energy band
flux_aper_avg_hilim double[6] ergs s-1 cm-2 aperture-corrected net energy flux inferred from the source region aperture, averaged over all contributing observations, and calculated by counting X-ray events (68% upper confidence limit) for each science energy band
flux_aper_avg_lolim double[6] ergs s-1 cm-2 aperture-corrected net energy flux inferred from the source region aperture, averaged over all contributing observations, and 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 net energy flux inferred from the source region aperture, best estimate derived from the longest block of a multi-band, flux-ordered Bayesian Block analysis of the contributing observations, and calculated by counting X-ray events (68% upper confidence limit) for each science energy band
flux_aper_lolim double[6] ergs s-1 cm-2 aperture-corrected net energy flux inferred from the source region aperture, best estimate derived from the longest block of a multi-band, flux-ordered Bayesian Block analysis of the contributing observations, and calculated by counting X-ray events (68% lower confidence limit) for each science energy band
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_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_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_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_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_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_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_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)
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_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_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_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_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_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_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_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_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)
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_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_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_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_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_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_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_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_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)
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)
gal_b double deg source position, Galactic latitude (equinox J2000.0, epoch J2000.0)
gal_l double deg source position, galactic longitude (equinox J2000.0, epoch J2000.0)
hard_hm double ACIS hard (2.0-7.0 keV) - medium (1.2-2.0 keV) energy band hardness ratio
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_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_hs double ACIS hard (2.0-7.0 keV) - soft (0.5-1.2 keV) energy band hardness ratio
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_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_ms double ACIS medium (1.2-2.0 keV) - soft (0.5-1.2 keV) energy band hardness ratio
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)
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)
hrc_hetg_num integer total number of HRC/HETG observations contributing to the Master Sources Table record of the source
hrc_hetg_time double total livetime for all HRC/HETG observations contributing to the Master Sources Table record of the source
hrc_letg_num integer total number of HRC/LETG observations contributing to the Master Sources Table record of the source
hrc_letg_time double total livetime for all HRC/LETG observations contributing to the Master Sources Table record of the source
hrc_num integer total number of HRC imaging observations contributing to the Master Sources Table record of the source
hrc_time double total livetime for all HRC imaging observations contributing to the Master Sources Table record of the source
kp_intra_prob double[6] intra-observation Kuiper's test variability probability (highest value across all observations); ACIS for each science energy band
ks_intra_prob double[6] intra-observation Kolmogorov-Smirnov test variability probability (highest value across all observations) for each science energy band
likelihood double highest detection log-likelihood across all stacked observations and science energy bands
likelihood_class string highest detection likelihood classification across all stacked observations and science energy bands
major_axis double[6] arcseconds 1σ radius along the major axis of the ellipse defining the deconvolved source extent for each science energy band
major_axis_hilim double[6] arcseconds 1σ radius along the major axis of the ellipse defining the deconvolved source extent (68% upper confidence limit) for each science energy band
major_axis_lolim double[6] arcseconds 1σ radius along the major axis of the ellipse defining the deconvolved source extent (68% lower confidence limit) for each science energy band
man_add_flag Boolean source was manually added in the catalog via human review
man_inc_flag Boolean source was manually included in the catalog via human review (detection was rejected by automated criteria)
man_match_flag Boolean source detections were manually matched between overlapping stacked observations via human review
man_pos_flag Boolean best fit source position was manually modified via human review
man_reg_flag Boolean source region parameters (dimensions, initial guess position input to the Maximum Likelihood Estimator fit) were manually modified via human review
minor_axis double[6] arcseconds 1σ radius along the minor axis of the ellipse defining the deconvolved source extent for each science energy band
minor_axis_hilim double[6] arcseconds 1σ radius along the minor axis of the ellipse defining the deconvolved source extent (68% upper confidence limit) for each science energy band
minor_axis_lolim double[6] arcseconds 1σ radius along the minor axis of the ellipse defining the deconvolved source extent (68% lower confidence limit) for each science energy band
name string source name in the form "2CXO Jhhmmss.s{+|-}ddmmss"
nh_gal double HI atoms 1020 cm-2 Galactic NH column density in direction of source
phot_nsrcs long number of sources simultaneously fit to compute aperture photometry quantitites
photflux_aper double[6] photons s-1 cm-2 aperture-corrected net photon flux inferred from the source region aperture, best estimate derived from the longest block of a multi-band, flux-ordered Bayesian Block analysis of the contributing observations, and calculated by counting X-ray events for each science energy band
photflux_aper90 double[6] photons s-1 cm-2 aperture-corrected net photon flux inferred from the PSF 90% ECF aperture, best estimate derived from the longest block of a multi-band, flux-ordered Bayesian Block analysis of the contributing observations, and calculated by counting X-ray events for each science energy band
photflux_aper90_avg double[6] photons s-1 cm-2 aperture-corrected net photon flux inferred from the PSF 90% ECF aperture, averaged over all contributing observations, and calculated by counting X-ray events for each science energy band
photflux_aper90_avg_hilim double[6] photons s-1 cm-2 aperture-corrected net photon flux inferred from the PSF 90% ECF aperture, averaged over all contributing observations, and calculated by counting X-ray events (68% upper confidence limit) for each science energy band
photflux_aper90_avg_lolim double[6] photons s-1 cm-2 aperture-corrected net photon flux inferred from the PSF 90% ECF aperture, averaged over all contributing observations, and 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 net photon flux inferred from the PSF 90% ECF aperture, best estimate derived from the longest block of a multi-band, flux-ordered Bayesian Block analysis of the contributing observations, and calculated by counting X-ray events (68% upper confidence limit) for each science energy band
photflux_aper90_lolim double[6] photons s-1 cm-2 aperture-corrected net photon flux inferred from the PSF 90% ECF aperture, best estimate derived from the longest block of a multi-band, flux-ordered Bayesian Block analysis of the contributing observations, and calculated by counting X-ray events (68% lower confidence limit) for each science energy band
photflux_aper_avg double[6] photons s-1 cm-2 aperture-corrected net photon flux inferred from the source region aperture, averaged over all contributing observations, and calculated by counting X-ray events for each science energy band
photflux_aper_avg_hilim double[6] photons s-1 cm-2 aperture-corrected net photon flux inferred from the source region aperture, averaged over all contributing observations, and calculated by counting X-ray events (68% upper confidence limit) for each science energy band
photflux_aper_avg_lolim double[6] photons s-1 cm-2 aperture-corrected net photon flux inferred from the source region aperture, averaged over all contributing observations, and 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 net photon flux inferred from the source region aperture, best estimate derived from the longest block of a multi-band, flux-ordered Bayesian Block analysis of the contributing observations, and calculated by counting X-ray events (68% upper confidence limit) for each science energy band
photflux_aper_lolim double[6] photons s-1 cm-2 aperture-corrected net photon flux inferred from the source region aperture, best estimate derived from the longest block of a multi-band, flux-ordered Bayesian Block analysis of the contributing observations, and calculated by counting X-ray events (68% lower confidence limit) for each science energy band
pileup_flag Boolean ACIS pile-up fraction exceeds ~10% in all observations; source properties may be affected
pos_angle double[6] deg position angle (referenced from local true north) of the major axis of the ellipse defining the deconvolved source extent 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 source extent (68% upper confidence limit) 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 source extent (68% lower confidence limit) for each science energy band
powlaw_ampl double amplitude of the best fitting absorbed power-law model spectrum to the source region aperture PI spectrum
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_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_rhat double amplitude convergence criterion of the best fitting absorbed power-law model spectrum to the source region aperture PI spectrum
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_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_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_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_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_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_rhat double NH column density 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
ra double deg source position, ICRS right ascension
sat_src_flag Boolean source is saturated in all observations; source properties are unreliable
significance double highest flux significance across all stacked observations and science energy bands
src_area double[6] sq. arcseconds area of the deconvolved source extent ellipse, or area of the source polygon for extended sources for each science energy band
streak_src_flag Boolean source is located on an ACIS readout streak in all observations; source properties may be affected
var_flag Boolean source displays flux variability within one or more observations, or between observations, in one or more energy bands
var_inter_hard_flag Boolean source hardness ratios are statistically inconsistent between two or more observations
var_inter_hard_prob_hm double inter-observation ACIS hard (2.0-7.0 keV) - medium (1.2-2.0 keV) energy band hardness ratio variability probability
var_inter_hard_prob_hs double inter-observation ACIS hard (2.0-7.0 keV) - soft (0.5-1.2 keV) energy band hardness ratio variability probability
var_inter_hard_prob_ms double inter-observation ACIS medium (1.2-2.0 keV) - soft (0.5-1.2 keV) energy band hardness ratio variability probability
var_inter_index integer[6] inter-observation variability index in the range [0, 10]: indicates whether the source region photon flux is constant between observations for each science energy band
var_inter_prob double[6] inter-observation variability probability, calculated from the chi^2 distribution of the photon fluxes of the individual observations for each science energy band
var_inter_sigma double[6] photons s-1 cm-2 inter-observation flux variability standard deviation; the spread of the individual observation photon fluxes about the error weighted mean for each science energy band
var_inter_sigma_prob_hm double inter-observation ACIS hard (2.0-7.0 keV) - medium (1.2-2.0 keV) energy band hardness ratio variability standard deviation
var_inter_sigma_prob_hs double inter-observation ACIS hard (2.0-7.0 keV) - soft (0.5-1.2 keV) energy band hardness ratio variability standard deviation
var_inter_sigma_prob_ms double inter-observation ACIS medium (1.2-2.0 keV) - soft (0.5-1.2 keV) energy band hardness ratio variability standard deviation
var_intra_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 observations) for each science energy band
var_intra_prob double[6] intra-observation Gregory-Loredo variability probability (highest value across all observations) for each science energy band