ChIcAGO Survey Chandra X-Ray Source Catalog

ChIcAGO Survey Chandra X-Ray Source Catalog CHICAGOCXO ivo://nasa.heasarc/chicagocxo NASA/GSFC HEASARC Anderson et al. 2026-10-09 NASA/GSFC HEASARC help desk heasarc-vo at athena.gsfc.nasa.gov Survey Source This table contains results from the 'Chasing the Identification of ASCA Galactic Objects' (ChIcAGO) survey, which is designed to identify the unknown X-ray sources discovered during the ASCA Galactic Plane Survey (AGPS). Little is known about most of the AGPS sources, especially those that emit primarily in hard X-rays (2-10 keV) within the X-ray flux range from ~ 10-13 to 10-11 erg cm-2 s-1. In ChIcAGO, the sub-arcsecond localization capabilities of Chandra have been combined with a detailed multi-wavelength follow-up program, with the ultimate goal of classifying the > 100 unidentified sources in the AGPS. Overall to date, 93 unidentified AGPS sources have been observed with Chandra as part of the ChIcAGO survey. A total of 253 X-ray point sources have been detected in these Chandra observations within 3 arcminutes of the original ASCA positions. The authors have identified infrared and optical counterparts to the majority of these sources, using both new observations and catalogs from existing Galactic plane surveys. X-ray and infrared population statistics for the X-ray point sources detected in the Chandra observations reveal that the primary populations of Galactic plane X-ray sources that emit in the X-ray flux range from ~ 10-13 to 10-11 erg cm-2 s-1 are active stellar coronae, massive stars with strong stellar winds that are possibly in colliding wind binaries, X-ray binaries, and magnetars. There is also another primary population that is still unidentified but, on the basis of its X-ray and infrared properties, likely comprises partly Galactic sources and partly active galactic nuclei. A total of 93 AGPS sources have been observed with Chandra as part of the ChIcAGO survey, of which 84 were imaged with ACIS-S and 9 were imaged with HRC-I. The ChIcAGO Chandra observations took place over a 3.5 yr period, from 2007 January to 2010 July. The Chandra exposure times ranged from ~ 1 to 10 ks. All the details of these Chandra observations are listed in Table 1 of the reference paper. The initial automated analysis of these Chandra observations was conducted using the ChIcAGO Multi-wavelength Analysis Pipeline (MAP), described in Section 2.2 of the reference paper. ChIcAGO MAP takes the ACIS-S or HRC-I Chandra observation of an AGPS source field and detects and analyzes all point sources within 3 arcminutes, equivalent to the largest likely position error, for the original AGPS source positions supplied by Sugizaki et al. (2001, ApJS, 134, 77). The authors then performed a more detailed X-ray analysis and counterpart study for those 74 sources with > 20 X-ray counts, as such sources are approximately within the original AGPS sources X-ray flux range (see Sections 3.2 and 3.3 of the reference paper). Infrared and optical follow-up were primarily performed on those ChIcAGO sources having > 20 X-ray counts. In order to determine which optical and infrared sources are counterparts to ChIcAGO sources, the authors used a technique similar to that described by Zhao et al. (2005, ApJS, 161, 429), using their Equation (11). If the separation between a ChIcAGO source's wavdetect position and its possible counterpart is less than the quadratic sum of their 3-sigma positional errors and the 3-sigma Chandra pointing error, then the X-ray and optical (or infrared) sources are likely to be associated. The 1-sigma positional errors for all sources in the 2MASS PSC and GLIMPSE catalogs are 0.1 arcseconds and 0.3 arcseconds, respectively. USNO B has an astrometric accuracy of < 0.25 arcseconds. The authors have assumed that the error distributions of the Chandra observations, Chandra pointing, and USNO B Catalog are all Gaussian for the purposes of identifying possible counterparts to the ChIcAGO sources. This table was created by the HEASARC in June 2014 based on electronic versions of Tables 1, 2 and 12 from the reference paper which were obtained from the ApJS website. This is a service provided by NASA HEASARC . 2014ApJS..212...13A https://heasarc.gsfc.nasa.gov/W3Browse/all/chicagocxo.html Catalog Research served-by HEASARC TAP https://heasarc.gsfc.nasa.gov/xamin/vo/cone?showoffsets&table=chicagocxo& GET text/xml 180 99999 true 217.95908333 -60.36897222 0.0166666666666667 https://heasarc.gsfc.nasa.gov/xamin/vo/tap https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/getvotable.pl?name=chicagocxo GET text/xml https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/w3query.pl?tablehead=name=heasarc_chicagocxo&Action=More+Options&Action=Parameter+Search&ConeAdd=1 CHANDRA 0.0166666666666667 Infrared X-ray public chicagocxo ChIcAGO Survey Chandra X-Ray Source Catalog agps_name AGPS Source Identifier meta.id char nullable name ChIcAGO Source Identifier meta.id;meta.main char nullable alt_name Most Commonly Used Identifier meta.id char nullable cxo_instrument Chandra Instrument Used instr;instr.det char nullable exposure Exposure Time s time.duration;obs.exposure double nullable ra Right Ascension degree pos.eq.ra;meta.main double nullable dec Declination degree pos.eq.dec;meta.main double nullable fb_counts Net 0.3-8 keV Band Counts ct phot;em.X-ray double nullable fb_counts_neg_err Lower Uncertainty for Net 0.3-8 keV Band Counts ct stat.error;phot;em.X-ray double nullable fb_counts_pos_err Upper Uncertainty for Net 0.3-8 keV Band Counts ct stat.error;phot;em.X-ray double nullable twomass_name 2MASS Source Identifier meta.id.cross char nullable jmag J-Band Magnitude mag phot.mag;em.IR.J double nullable jmag_error Uncertainty in J-Band Magnitude mag stat.error;phot.mag;em.IR.J double nullable "__x_ra_dec" System unit vector column double nullable "__y_ra_dec" System unit vector column double nullable "__z_ra_dec" System unit vector column double nullable "__row" System index column char nullable wav_error_radius Wav Positional Error arcsec stat.error;pos double nullable hmag_error Uncertainty in H-Band Magnitude mag stat.error;phot.mag;em.IR.H double nullable jmag_limit Limit Flag for J-Band Magnitude meta.code;phot.mag;em.IR.J char nullable detect_flag Flag [FG] Indicates F=Probably a False Detection or G=Source Falls in Chip Gap meta.code;src char nullable chicago_matches ChIcAGO Source Matches meta.id.cross char nullable irac_8p0_um_mag_error Uncertainty in GLIMPSE 8.0-Micron Band Magnitude mag stat.error;phot.mag;em.IR.4-8um double nullable csc_name Chandra Source Catalog Identifier (Evans et al. 2010) meta.id.cross char nullable ks_mag_error Uncertainty in K-Band Magnitude mag stat.error;phot.mag;em.IR.K double nullable ks_mag K-Band Magnitude mag phot.mag;em.IR.K double nullable sb_counts Net 0.5-2 keV Band Counts ct phot;em.X-ray.soft double nullable glimpse_name GLIMPSE Source Identifier meta.id.cross char nullable match_flag Flag [YN] Indicates Source Not Detected by Chandra meta.code char nullable panic_date Date of PANIC Observation mjd time;obs int nullable hb_counts Net 2-8 keV Band Counts ct phot;em.X-ray.medium double nullable irac_8p0_um_mag GLIMPSE 8.0-Micron Band Magnitude mag phot.mag;em.IR.4-8um double nullable class Browse Object Classification src.class short nullable irac_8p0_um_mag_flag Flag [d] Indicates Value Obtained from GLIMPSE Archives Rather Than Catalogs meta.code;phot.mag;em.IR.4-8um char nullable reference_codes Reference(s) meta.ref char nullable nir_data_codes NIR Data Codes meta.code char nullable hmag_limit Limit Flag for H-Band Magnitude meta.code;phot.mag;em.IR.H char nullable quartile_ratio_error Uncertainty in Quartile Ratio stat.error;stat.param;phys.energy double nullable cxo_date Date of the Chandra Observation mjd time;obs int nullable irac_5p8_um_mag_error Uncertainty in GLIMPSE 5.8-Micron Band Magnitude mag stat.error;phot.mag;em.IR.4-8um double nullable irac_5p8_um_mag GLIMPSE 5.8-Micron Band Magnitude mag phot.mag;em.IR.4-8um double nullable irac_5p8_um_mag_flag Flag [d] Indicates Value Obtained from GLIMPSE Archives Rather Than Catalogs meta.code;phot.mag;em.IR.4-8um char nullable obsid Chandra Observation Identification Number meta.id;obs int nullable hb_counts_neg_err Lower Uncertainty for Net 2-8 keV Band Counts ct stat.error;phot;em.X-ray.medium double nullable error_radius Total Positional Error arcsec stat.error;pos double nullable id_flags Flags Indicate Identification Properties of the AGPS and ChIcAGO Sources meta.code;src char nullable cxo_asca_offset Offset from ASCA Position arcmin pos.angDistance;em.X-ray double nullable lii Galactic Longitude degree pos.galactic.lon double nullable irac_3p6_um_mag_flag Flag [d] Indicates Value Obtained from GLIMPSE Archives Rather Than Catalogs meta.code;phot.mag;em.IR.3-4um char nullable s2001_flag Flag [CI] Indicates Correct or Incorrect Identification by Sugizaki et al. 2001 meta.code char nullable irac_4p5_um_mag GLIMPSE 4.5-Micron Band Magnitude mag phot.mag;em.IR.4-8um double nullable irac_3p6_um_mag GLIMPSE 3.6-Micron Band Magnitude mag phot.mag;em.IR.3-4um double nullable hb_counts_pos_err Upper Uncertainty for Net 2-8 keV Band Counts ct stat.error;phot;em.X-ray.medium double nullable phot_energy_50pc 50% Photon Detected in 0.3-8 keV Band keV phys.energy double nullable hmag H-Band Magnitude mag phot.mag;em.IR.H double nullable phot_energy_50pc_error Uncertainty in 50% Photon Detected in 0.3-8 keV Band keV stat.error;phys.energy double nullable ks_mag_limit Limit Flag for K-Band Magnitude meta.code;phot.mag;em.IR.K char nullable irac_3p6_um_mag_error Uncertainty in GLIMPSE 3.6-Micron Band Magnitude mag stat.error;phot.mag;em.IR.3-4um double nullable bii Galactic Latitude degree pos.galactic.lat double nullable sb_counts_pos_err Upper Uncertainty for Net 0.5-2 keV Band Counts ct stat.error;phot;em.X-ray.soft double nullable xmm_name 2XMMi-DR3 Source Identifier (Watson et al. 2009) meta.id.cross char nullable irac_4p5_um_mag_flag Flag [d] Indicates Value Obtained from GLIMPSE Archives Rather Than Catalogs meta.code;phot.mag;em.IR.4-8um char nullable irac_4p5_um_mag_error Uncertainty in GLIMPSE 4.5-Micron Band Magnitude mag stat.error;phot.mag;em.IR.4-8um double nullable source_type Type of Source src.class char nullable sb_counts_neg_err Lower Uncertainty for Net 0.5-2 keV Band Counts ct stat.error;phot;em.X-ray.soft double nullable quartile_ratio Quartile Ratio stat.param;phys.energy double nullable