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.
Column Name | Type | Units | Description |
---|---|---|---|
ao | integer | Announcement of Opportunity (AO) number for the Chandra observing cycle in which the observation was scheduled | |
apec_abund | double | best-fit metal abundances (Abundanc) | |
apec_abund_hilim | double | upper limit on the 68% confidence interval of the "apec_abund" value | |
apec_abund_lolim | double | lower limit on the 68% confidence interval of the "apec_abund" value | |
apec_abund_rhat | double | convergence criterion for "apec_abund" | |
apec_kt | double | keV | best-fit APEC plasma temperature (kT) |
apec_kt_hilim | double | keV | upper limit on the 68% confidence interval of the "apec_kt" value |
apec_kt_lolim | double | keV | lower limit on the 68% confidence interval of the "apec_kt" value |
apec_kt_rhat | double | convergence criterion for "apec_kt" | |
apec_nh | double | N _{HI atoms} 10^{20} cm^{-2} | best-fit APEC N_{H} value |
apec_nh_hilim | double | N _{HI atoms} 10^{20} cm^{-2} | upper limit on the 68% confidence interval of the "apec_nh" value |
apec_nh_lolim | double | N _{HI atoms} 10^{20} cm^{-2} | lower limit on the 68% confidence interval of the "apec_nh" value |
apec_nh_rhat | double | convergence criterion for "apec_nh" | |
apec_norm | double | normalization factor of the best fitting APEC plasma model | |
apec_norm_hilim | double | upper limit on the 68% confidence interval of the "apec_norm" value | |
apec_norm_lolim | double | lower limit on the 68% confidence interval of the "apec_norm" value | |
apec_norm_rhat | double | convergence criterion for "apec_norm" | |
apec_stat | double | χ^{2} (data variance) statistic per degree of freedom for the best-fitting absorbed APEC spectral fit | |
apec_z | double | best-fit APEC redshift (z) | |
apec_z_hilim | double | upper limit on the 68% confidence interval of the "apec_z" value | |
apec_z_lolim | double | lower limit on the 68% confidence interval of the "apec_z" value | |
apec_z_rhat | double | convergence criterion for "apec_z" | |
area_aper | double | sq. arcsec | area of the modified elliptical source region aperture (includes corrections for exclusion regions due to overlapping detections) |
area_aper90 | double[6] | sq. arcseconds | area of the modified elliptical aperture from the PSF 90% ECF for each science energy band |
area_aper90bkg | double[6] | sq. arcseconds | area of the modified annular background aperture from the PSF 90% ECF for each science energy band |
area_aperbkg | double | sq. arcseconds | area of the modified annular background region aperture (includes corrections for exclusion regions due to overlapping detections) |
ascdsver | string | software version used to create the Level 3 event file | |
bb_ampl | double | amplitude of the best fitting absorbed blackbody model spectral fit to the PI event data extracted from the source region | |
bb_ampl_hilim | double | upper confidence limit on "bb_ampl" | |
bb_ampl_lolim | double | lower confidence limit on "bb_ampl" | |
bb_ampl_rhat | double | convergence criterion for "bb_ampl" | |
bb_kt | double | keV | best-fit thermal (black body) temperature (kT) |
bb_kt_hilim | double | keV | upper limit on the 68% confidence interval of the "bb_kt" value |
bb_kt_lolim | double | keV | lower limit on the 68% confidence interval of the "bb_kt" value |
bb_kt_rhat | double | convergence criterion for "bb_kt" | |
bb_nh | double | N _{HI atoms} 10^{20} cm^{-2} | best-fit thermal (black body) N_{H} value |
bb_nh_hilim | double | N _{HI atoms} 10^{20} cm^{-2} | upper limit on the 68% confidence interval of the "bb_nh" value |
bb_nh_lolim | double | N _{HI atoms} 10^{20} cm^{-2} | lower limit on the 68% confidence interval of the "bb_nh" value |
bb_nh_rhat | double | convergence criterion for "bb_nh" | |
bb_stat | double | χ^{2} (data variance) statistic per degree of freedom for the best-fitting thermal (blackbody) spectral fit | |
brems_kt | double | keV | best-fit thermal bremsstrahlung temperature (kT) |
brems_kt_hilim | double | keV | upper limit on the 68% confidence interval of the "brems_kt" value |
brems_kt_lolim | double | keV | lower limit on the 68% confidence interval of the "brems_kt" value |
brems_kt_rhat | double | convergence criterion for "brems_kt" | |
brems_nh | double | N _{HI atoms} 10^{20} cm^{-2} | best-fit thermal bremsstrahlung N_{H} value |
brems_nh_hilim | double | N _{HI atoms} 10^{20} cm^{-2} | upper limit on the 68% confidence interval of the "brems_nh" value |
brems_nh_lolim | double | N _{HI atoms} 10^{20} cm^{-2} | lower limit on the 68% confidence interval of the "brems_nh" value |
brems_nh_rhat | double | convergence criterion for "brems_nh" | |
brems_norm | double | normalization factor of the best fitting thermal bremsstrahlung model | |
brems_norm_hilim | double | upper limit on the 68% confidence interval of the "brems_norm" value | |
brems_norm_lolim | double | lower limit on the 68% confidence interval of the "brems_norm" value | |
brems_norm_rhat | double | convergence criterion for "brems_norm" | |
brems_stat | double | χ^{2} (data variance) statistic per degree of freedom for the best-fitting absorbed thermal bremsstrahlung spectral fit | |
caldbver | string | calibration database version used to create the Level 3 event file | |
chip_id | integer | reference ACIS CCD or HRC segment for (chipx, chipy) | |
chip_id_pnt | integer | reference ACIS CCD or HRC segment for (chipx_pnt, chipy_pnt) | |
chipx | double | pixel | the chipx position corresponding to the off-axis angles (θ, φ) of the source |
chipx_pnt | double | pixel | chipx corresponding to (ra_pnt, dec_pnt) |
chipy | double | pixel | the chipy position corresponding to the off-axis angles (θ, φ) of the source |
chipy_pnt | double | pixel | chipy corresponding to (ra_pnt, dec_pnt) |
cnts_aper | long[6] | counts | total counts measured in the modified source region for each science energy band |
cnts_aper90 | long[6] | counts | total counts measured in the modified elliptical aperture for each science energy band |
cnts_aper90bkg | long[6] | counts | total counts measured in the modified elliptical background aperture for each science energy band |
cnts_aperbkg | long[6] | counts | total counts measured in the modified background region for each science energy band |
conf_code | integer[6] | indicates whether the source is in a confused region in any source detection energy band | |
crdate | string | creation date and time (UTC) of the Level 3 event file | |
cycle | string | cycle for alternating exposure (interleaved) mode observations: P (primary) or S (secondary); ACIS only. Value is P for full-frame observations. | |
datamode | string | data mode used for the observation | |
dec_aper90 | double[6] | deg | ICRS declination of the center of the 90% Encircled Counts Fraction of the PSF for each science energy band |
dec_nom | double | deg | ICRS declination of the tangent point |
dec_pnt | double | deg | ICRS declination of the mean pointing |
dec_targ | double | deg | ICRS declination of the target |
deltarot | double | deg | roll angle update from fine astrometry applied to computed asol3 file |
deltax | double | arcsec | X translation update from fine astrometry applied to computed asol3 file |
deltay | double | arcsec | Y translation update from fine astrometry applied to computed asol3 file |
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. | |
dither_warning_flag | boolean | TRUE if the highest statistically significant peak in the power spectrum of the source region count rate for each science energy band occurs either at the dither frequency of the observation or at a beat frequency of the dither frequency. Otherwise, the value is FALSE. | |
dscale | double | deg | scale factor update from fine astrometry applied to computed asol3 file |
dtheta | double | deg | mean dtheta position during observation |
dy | double | mm | mean dy position during observation |
dz | double | mm | mean dz position during observation |
edge_code | coded byte | indicates that the position or region dithered off a chip boundary | |
exptime | double | CCD frame time; ACIS only | |
extent_code | integer[6] | indicates whether the source is extended in all science energy bands | |
flux_apec | double | ergs s^{-1} cm^{-2} | integrated 0.5-7.0 keV flux derived from the best-fitting APEC spectral fit |
flux_apec_aper | double[6] | ergs s^{-1} cm^{-2} | APEC model energy flux inferred from the modified source region for each science energy band |
flux_apec_aper90 | double[6] | ergs s^{-1} cm^{-2} | APEC model energy flux inferred from the PSF 90% ECF aperture for each science energy band |
flux_apec_aper90_hilim | double[6] | ergs s^{-1} cm^{-2} | upper limit on the 68% confidence interval of the "flux_apec_aper90" value for each science energy band |
flux_apec_aper90_lolim | double[6] | ergs s^{-1} cm^{-2} | lower limit on the 68% confidence interval of the "flux_apec_aper90" value for each science energy band |
flux_apec_aper_hilim | double[6] | ergs s^{-1} cm^{-2} | upper limit on the 68% confidence interval of the "flux_apec_aper" value for each science energy band |
flux_apec_aper_lolim | double[6] | ergs s^{-1} cm^{-2} | lower limit on the 68% confidence interval of the "flux_apec_aper" value for each science energy band |
flux_apec_hilim | double | ergs s^{-1} cm^{-2} | upper limit on the 68% confidence interval of the "flux_apec" value |
flux_apec_lolim | double | ergs s^{-1} cm^{-2} | lower limit on the 68% confidence interval of the "flux_apec" value |
flux_aper | double[6] | ergs s^{-1} cm^{-2} | background-subtracted flux inferred from the modified source region for each science energy band |
flux_aper90 | double[6] | ergs s^{-1} cm^{-2} | background-subtracted flux inferred from the modified elliptical aperture for each science energy band |
flux_aper90_hilim | double[6] | ergs s^{-1} cm^{-2} | upper limit on the 68% confidence interval of the "flux_aper90" value for each science energy band |
flux_aper90_lolim | double[6] | ergs s^{-1} cm^{-2} | lower limit on the 68% confidence interval of the "flux_aper90" value for each science energy band |
flux_aper_hilim | double[6] | ergs s^{-1} cm^{-2} | upper limit on the 68% confidence interval of the "flux_aper" value for each science energy band |
flux_aper_lolim | double[6] | ergs s^{-1} cm^{-2} | lower limit on the 68% confidence interval of the "flux_aper" value for each science energy band |
flux_bb | double | ergs s^{-1} cm^{-2} | integrated 0.5-7.0 keV flux derived from the best-fitting thermal (black body) spectral fit |
flux_bb_aper | double[6] | ergs s^{-1} cm^{-2} | black body model energy flux inferred from the modified source region for each science energy band |
flux_bb_aper90 | double[6] | ergs s^{-1} cm^{-2} | black body model energy flux inferred from the PSF 90% ECF aperture for each science energy band |
flux_bb_aper90_hilim | double[6] | ergs s^{-1} cm^{-2} | upper limit on the 68% confidence interval of the "flux_bb_aper90" value for each science energy band |
flux_bb_aper90_lolim | double[6] | ergs s^{-1} cm^{-2} | lower limit on the 68% confidence interval of the "flux_bb_aper90" value for each science energy band |
flux_bb_aper_hilim | double[6] | ergs s^{-1} cm^{-2} | upper limit on the 68% confidence interval of the "flux_bb_aper" value for each science energy band |
flux_bb_aper_lolim | double[6] | ergs s^{-1} cm^{-2} | lower limit on the 68% confidence interval of the "flux_bb_aper" value for each science energy band |
flux_bb_hilim | double | ergs s^{-1} cm^{-2} | upper limit on the 68% confidence interval of the "flux_bb" value |
flux_bb_lolim | double | ergs s^{-1} cm^{-2} | lower limit on the 68% confidence interval of the "flux_bb" value |
flux_brems | double | ergs s^{-1} cm^{-2} | integrated 0.5-7.0 keV flux derived from the best-fitting thermal bremsstrahlung spectral fit |
flux_brems_aper | double[6] | ergs s^{-1} cm^{-2} | bremsstrahlung model energy flux inferred from the modified source region for each science energy band |
flux_brems_aper90 | double[6] | ergs s^{-1} cm^{-2} | bremsstrahlung model energy flux inferred from the PSF 90% ECF aperture for each science energy band |
flux_brems_aper90_hilim | double[6] | ergs s^{-1} cm^{-2} | upper limit on the 68% confidence interval of the "flux_brems_aper90" value for each science energy band |
flux_brems_aper90_lolim | double[6] | ergs s^{-1} cm^{-2} | lower limit on the 68% confidence interval of the "flux_brems_aper90" value for each science energy band |
flux_brems_aper_hilim | double[6] | ergs s^{-1} cm^{-2} | upper limit on the 68% confidence interval of the "flux_brems_aper" value for each science energy band |
flux_brems_aper_lolim | double[6] | ergs s^{-1} cm^{-2} | lower limit on the 68% confidence interval of the "flux_brems_aper" value for each science energy band |
flux_brems_hilim | double | ergs s^{-1} cm^{-2} | upper limit on the 68% confidence interval of the "flux_brems" value |
flux_brems_lolim | double | ergs s^{-1} cm^{-2} | lower limit on the 68% confidence interval of the "flux_brems" value |
flux_powlaw | double | ergs s^{-1} cm^{-2} | integrated 0.5-7.0 keV flux derived from the best-fitting power law spectral fit |
flux_powlaw_aper | double[6] | ergs s^{-1} cm^{-2} | power law model energy flux inferred from the modified source region for each science energy band |
flux_powlaw_aper90 | double[6] | ergs s^{-1} cm^{-2} | power law model energy flux inferred from the PSF 90% ECF aperture for each science energy band |
flux_powlaw_aper90_hilim | double[6] | ergs s^{-1} cm^{-2} | upper limit on the 68% confidence interval of the "flux_powlaw_aper90" value for each science energy band |
flux_powlaw_aper90_lolim | double[6] | ergs s^{-1} cm^{-2} | lower limit on the 68% confidence interval of the "flux_powlaw_aper90" value for each science energy band |
flux_powlaw_aper_hilim | double[6] | ergs s^{-1} cm^{-2} | upper limit on the 68% confidence interval of the "flux_powlaw_aper" value for each science energy band |
flux_powlaw_aper_lolim | double[6] | ergs s^{-1} cm^{-2} | lower limit on the 68% confidence interval of the "flux_powlaw_aper" value for each science energy band |
flux_powlaw_hilim | double | ergs s^{-1} cm^{-2} | upper limit on the 68% confidence interval of the "flux_powlaw" value |
flux_powlaw_lolim | double | ergs s^{-1} cm^{-2} | lower limit on the 68% confidence interval of the "flux_powlaw" value |
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 | |
grating | string | grating used for the observation: NONE, HETG, or LETG | |
gti_elapse | double | s | total elapsed time of the observation. The total elapsed time is not equal to the total exposure time of the observation because periods of bad time may have been filtered out. |
gti_end | string | (TT) | stop time for the valid data in FITS standard format (ISO 8601) |
gti_mjd_obs | double | MJD (TT) | modified Julian date for the start time of the valid data |
gti_obs | string | (TT) | start time for the valid data in FITS standard format (ISO 8601) |
gti_start | double | s | start time for the valid data in mission elapsed time |
gti_stop | double | s | stop time for the valid data in mission elapsed time |
hard_hm | double | hardness ratio of the hard to medium ACIS science energy bands | |
hard_hm_hilim | double | upper confidence limit on "hard_hm" value | |
hard_hm_lolim | double | lower confidence limit on "hard_hm" value | |
hard_hs | double | hardness ratio of the hard to soft ACIS science energy bands | |
hard_hs_hilim | double | upper confidence limit on "hard_hs" value | |
hard_hs_lolim | double | lower confidence limit on "hard_hs" value | |
hard_ms | double | hardness ratio of the medium to soft ACIS science energy bands | |
hard_ms_hilim | double | upper confidence limit on "hard_ms" value | |
hard_ms_lolim | double | lower confidence limit on "hard_ms" value | |
instrument | string | instrument used for the observation: ACIS or HRC | |
kp_prob | double[6] | Kuiper's test probability for each science energy band | |
ks_prob | double[6] | Kolmogorov-Smirnov test probability for each science energy band | |
likelihood | double[6] | significance of the single-observation detection computed by the single-observation detection algorithm from the maximum likelihood for each source detection energy band | |
livetime | double | s | effective exposure time for the observation after applying the good time intervals and deadtime correction factor |
major_axis | double[6] | arcsec | best estimate value for the 1σ radius along the major axis of the rotated elliptical Gaussian parameterization of the deconvolved source extent ellipse for each science energy band |
major_axis_hilim | double[6] | arcsec | 1σ major radius of deconvolved elliptical Gaussian source fit 68% upper limit for each science energy band |
major_axis_lolim | double[6] | arcsec | 1σ major radius of deconvolved elliptical Gaussian source fit 68% lower limit for each science energy band |
man_astrom_flag | boolean | fine astrometry transform computed manually | |
minor_axis | double[6] | arcsec | best estimate value for 1σ radius along the minor axis of the rotated elliptical Gaussian parameterization of the deconvolved source extent ellipse for each science energy band |
minor_axis_hilim[6] | double | arcsec | 1σ minor radius of deconvolved elliptical Gaussian source fit 68% upper limit for each science energy band |
minor_axis_lolim | double[6] | arcsec | 1σ minor radius of deconvolved elliptical Gaussian source fit 68% lower limit for each science energy band |
mjd_ref | double | MJD (TT) | modified Julian date reference corresponding to zero seconds mission elapsed time |
mjr_axis1_aper90bkg | double[6] | arcsec | major axis of the inner annulus of the co-located, scaled elliptical background aperture for each science energy band |
mjr_axis2_aper90bkg | double[6] | arcsec | major axis of the outer annulus of the co-located, scaled elliptical background aperture for each science energy band |
mjr_axis_aper90 | double[6] | arcsec | major axis of the elliptical aperture that contains the 90% Encircled Counts Fraction of the PSF at the source location for each science energy band |
mjr_axis_raw | double[6] | arcsec | 1σ radius along the major axis of the rotated elliptical Gaussian parameterization of the raw extent of a source for each science energy band |
mjr_axis_raw_hilim | double[6] | arcsec | 68% error upper limit on the "mjr_axis_raw" value for each science energy band |
mjr_axis_raw_lolim | double[6] | arcsec | 68% error lower limit on the "mjr_axis_raw" value for each science energy band |
mnr_axis1_aper90bkg | double[6] | arcsec | minor axis of the inner annulus of the co-located, scaled elliptical background aperture for each science energy band |
mnr_axis2_aper90bkg | double[6] | arcsec | minor axis of the outer annulus of the co-located, scaled elliptical background aperture for each science energy band |
mnr_axis_aper90 | double[6] | arcsec | minor axis of the elliptical aperture that contains the 90% Encircled Counts Fraction of the PSF at the source location for each science energy band |
mnr_axis_raw | double[6] | arcsec | 1σ radius along the minor axis of the rotated elliptical Gaussian parameterization of the raw extent of a source for each science energy band |
mnr_axis_raw_hilim | double[6] | arcsec | 68% error upper limit on the "mnr_axis_raw" value for each science energy band |
mnr_axis_raw_lolim | double[6] | arcsec | 68% error lower limit on the "mnr_axis_raw" value for each science energy band |
multi_chip_code | coded byte | indicates that the position or region dithered over multiple chip boundaries | |
obi | integer | Observation Interval (ObI) | |
obsid | integer | Observation ID (ObsID) | |
phi | double | deg | PSF 90% ECF azimuthal angle, φ, of the source |
phot_nsrcs | integer[6] | number of sources simultaneously fit to compute aperture photometry quantities | |
photflux_aper | double[6] | photons s^{-1} cm^{-2} | background-subtracted flux inferred from the modified source region for each science energy band |
photflux_aper90 | double[6] | photons s^{-1} cm^{-2} | background-subtracted flux inferred from the modified elliptical aperture for each science energy band |
photflux_aper90_hilim | double[6] | photons s^{-1} cm^{-2} | upper limit on the 68% confidence interval of the "photflux_aper90" value for each science energy band |
photflux_aper90_lolim | double[6] | photons s^{-1} cm^{-2} | lower limit on the 68% confidence interval of the "photflux_aper90" value for each science energy band |
photflux_aper_hilim | double[6] | photons s^{-1} cm^{-2} | upper limit on the 68% confidence interval of the "photflux_aper" value for each science energy band |
photflux_aper_lolim | double[6] | photons s^{-1} cm^{-2} | lower limit on the 68% confidence interval of the "photflux_aper" value for each science energy band |
pileup_warning | double | counts/frame/pixel | indicates that the source properties may be affected by ACIS pileup |
pos_angle | double[6] | deg | best estimate value for the position angle of the rotated elliptical Gaussian parameterization of the deconvolved source extent ellipse of "major_axis" for each science energy band |
pos_angle_aper90 | double[6] | deg | position angle of the elliptical aperture that contains the 90% Encircled Counts Fraction of the PSF at the source location for each science energy band |
pos_angle_aper90bkg | double[6] | deg | position angle of the co-located, scaled elliptical background aperture for each science energy band |
pos_angle_hilim | double[6] | deg | position angle of "major_axis" 68% upper limit for each science energy band |
pos_angle_lolim | double[6] | deg | position angle of "major_axis" 68% lower limit for each science energy band |
pos_angle_raw | double[6] | deg | position angle of the rotated elliptical Gaussian parameterization of the raw extent of a source for each science energy band |
pos_angle_raw_hilim | double[6] | deg | 68% error upper limit on the "pos_angle_raw" value for each science energy band |
pos_angle_raw_lolim | double[6] | deg | 68% error lower limit on the "pos_angle_raw" value for each science energy band |
powlaw_ampl | double | amplitude of the best fitting power-law model spectral fit to the PI event data extracted from the source region | |
powlaw_ampl_hilim | double | upper confidence limit on "powlaw_ampl" | |
powlaw_ampl_lolim | double | lower confidence limit on "powlaw_ampl" | |
powlaw_ampl_rhat | double | convergence criterion for "powlaw_ampl" | |
powlaw_gamma | double | best-fit power law photon index (γ, defined as F_{E} ∼ E^{-γ}) | |
powlaw_gamma_hilim | double | upper limit on the 68% confidence interval of the "powlaw_gamma" value | |
powlaw_gamma_lolim | double | lower limit on the 68% confidence interval of the "powlaw_gamma" value | |
powlaw_gamma_rhat | double | convergence criterion for "powlaw_gamma" | |
powlaw_nh | double | N _{HI atoms} 10^{20} cm^{-2} | best-fit power law N_{H} value |
powlaw_nh_hilim | double | N _{HI atoms} 10^{20} cm^{-2} | upper limit on the 68% confidence interval of the "powlaw_nh" value |
powlaw_nh_lolim | double | N _{HI atoms} 10^{20} cm^{-2} | lower limit on the 68% confidence interval of the "powlaw_nh" value |
powlaw_nh_rhat | double | convergence criterion for "powlaw_nh" | |
powlaw_stat | double | χ^{2} (data variance) statistic per degree of freedom for the best-fitting absorbed power law spectral fit | |
psf_frac_aper | double[6] | fraction of the PSF included in the modified elliptical source region for each science energy band | |
psf_frac_aper90 | double[6] | fraction of the PSF included in the modified elliptical aperture from the PSF 90% ECF for each science energy band | |
psf_frac_aper90bkg | double[6] | fraction of the PSF included in the modified annular background aperture from the PSF 90% ECF for each science energy band | |
psf_frac_aperbkg | double[6] | fraction of the PSF included in the modified annular background region for each science energy band | |
psf_mjr_axis_raw | double[6] | arcsec | 1σ major axis of the rotated elliptical Gaussian parameterization of the raw extent of the PSF for each science energy band |
psf_mjr_axis_raw_hilim | double[6] | arcsec | 68% error upper limit on the "psf_mjr_axis_raw" value for each science energy band |
psf_mjr_axis_raw_lolim | double[6] | arcsec | 68% error lower limit on the "psf_mjr_axis_raw" value for each science energy band |
psf_mnr_axis_raw | double[6] | arcsec | 1σ minor axis of the rotated elliptical Gaussian parameterization of the raw extent of the PSF for each science energy band |
psf_mnr_axis_raw_hilim | double[6] | arcsec | 68% error upper limit on the "psf_mnr_axis_raw" value for each science energy band |
psf_mnr_axis_raw_lolim | double[6] | arcsec | 68% error lower limit on the "psf_mnr_axis_raw" value for each science energy band |
psf_pos_angle_raw | double[6] | deg | position angle of the 1σ rotated elliptical Gaussian parameterization of the raw extent of the PSF for each science energy band |
psf_pos_angle_raw_hilim | double[6] | deg | 68% error upper limit on the "psf_pos_angle_raw" value for each science energy band |
psf_pos_angle_raw_lolim | double[6] | deg | 68% error upper limit on the "psf_pos_angle_raw" value for each science energy band |
ra_aper90 | double[6] | deg | ICRS right ascension of the center of the 90% Encircled Counts Fraction of the PSF for each science energy band |
ra_nom | double | deg | ICRS right ascension of the tangent point |
ra_pnt | double | deg | ICRS right ascension of the mean pointing |
ra_targ | double | deg | ICRS right ascension of the target |
readmode | string | readout mode used for the observation: TIMED or CONTINUOUS; ACIS only | |
region_id | integer | source region within the observation | |
roll_nom | double | deg | roll angle of the tangent point |
roll_pnt | double | deg | roll angle of the mean pointing |
sat_src_flag | boolean | indicates a saturated source (strong ACIS pileup) | |
sim_x | double | mm | mean sim_x position during observation |
sim_z | double | mm | mean sim_z position during observation |
src_area | double[6] | sq. arcseconds | Equivalent source extent area calculated from the "major_axis" and "minor_axis" for each science energy band |
src_cnts_aper | double[6] | counts | net background-subtracted source counts inferred from the modified source region for each science energy band |
src_cnts_aper90 | double[6] | counts | net background-subtracted source counts inferred from the modified elliptical aperture for each science energy band |
src_cnts_aper90_hilim | double[6] | counts | net background-subtracted source counts inferred from the modified elliptical aperture 68% upper limit for each science energy band |
src_cnts_aper90_lolim | double[6] | counts | net background-subtracted source counts inferred from the modified elliptical aperture 68% lower limit for each science energy band |
src_cnts_aper_hilim | double[6] | counts | net background-subtracted source counts inferred from the modified source region 68% upper limit for each science energy band |
src_cnts_aper_lolim | double[6] | counts | net background-subtracted source counts inferred from the modified source region 68% lower limit for each science energy band |
src_rate_aper | double[6] | counts s^{-1} | background-subtracted source count rate inferred from the modified source region for each science energy band |
src_rate_aper90 | double[6] | counts s^{-1} | background-subtracted source count rate inferred from the modified elliptical aperture for each science energy band |
src_rate_aper90_hilim | double[6] | counts s^{-1} | upper limit on the 68% confidence interval of the "src_rate_aper90" value for each science energy band |
src_rate_aper90_lolim | double[6] | counts s^{-1} | lower limit on the 68% confidence interval of the "src_rate_aper90" value for each science energy band |
src_rate_aper_hilim | double[6] | counts s^{-1} | upper limit on the 68% confidence interval of the "src_rate_aper" value for each science energy band |
src_rate_aper_lolim | double[6] | counts s^{-1} | lower limit on the 68% confidence interval of the "src_rate_aper" value for each science energy band |
streak_src_flag | boolean | indicates that the source lies on an ACIS readout streak | |
targname | string | target name for the observation | |
theta | double | arcmin | PSF 90% ECF off-axis angle, θ, of the source |
timing_mode | boolean | TRUE if the observation was done in precision timing mode, FALSE if not; HRC only | |
var_code | coded byte | indicates source variability in any science energy band | |
var_index | integer[6] | variability index in the range [0,10] for each science energy band that combines the "var_prob" value with the fractions of the multi-resolution light curve output by the Gregory-Loredo analysis that are within 3σ and 5σ of the average count rate, to evaluate whether the source region flux is uniform throughout the observation | |
var_max | double[6] | counts s^{-1} | maximum value of the source region count rate for each science energy band |
var_mean | double[6] | counts s^{-1} | time-averaged value of the source region count rate for each science energy band |
var_min | double[6] | counts s^{-1} | minimum value of the source region count rate for each science energy band |
var_prob | double[6] | Gregory-Loredo variability probability for each science energy band | |
var_sigma | double[6] | counts s^{-1} | time-averaged 1σ statistical variability of the source region count rate for each science energy band |