Chandra Nearby Spiral Galaxies Point Source Catalog ChanNSPiral ivo://nasa.heasarc/channsgpsc NASA/GSFC HEASARC Kilgard et al. 2026-10-09 NASA/GSFC HEASARC help desk heasarc-vo at athena.gsfc.nasa.gov Survey Source Emission from discrete point sources dominates the X-ray luminosity in spiral galaxies. This table contains the results from a survey of 11 nearby, nearly face-on spiral galaxies observed with the Chandra X-ray Observatory in 22 observations for a total of 869 ks. The galaxies in this sample are at high Galactic latitude to minimize the absorbing column in the line of site, are nearby to minimize source confusion, and span the Hubble sequence for spirals (types 0-7), allowing insights into the X-ray source population of many diverse systems. More than 820 unique point sources are detected in at least one observation within the D25 ellipses of the galaxies. A minimum of 27% of the sources exhibit detectable long- or short-term variability, indicating a source population dominated by accreting XRBs. 17 ultraluminous X-ray sources are detected, with typical rates per galaxy of 1 or 2. In this table, source lists for the 11 galaxies are presented, along with source counts, fluxes, luminosities, X-ray colors, and variability properties. It should be noted that the X-ray source counts presented in this table are raw, background-subtracted counts, so the count rates in sources from the same galaxy that fall on different CCDs cannot be directly compared. The colors presented have been corrected for the differences between front-illuminated and back-illuminated CCDs. This table was created by the HEASARC in November 2006 based on the electronic version of Table 4 obtained from the electronic ApJ web site. This is a service provided by NASA HEASARC . 2005ApJS..159..214K https://heasarc.gsfc.nasa.gov/W3Browse/all/channsgpsc.html Catalog Research served-by HEASARC TAP https://heasarc.gsfc.nasa.gov/xamin/vo/cone?showoffsets&table=channsgpsc& GET text/xml 180 99999 true 49.33370833 -41.18605278 0.0166666666666667 https://heasarc.gsfc.nasa.gov/xamin/vo/tap https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/getvotable.pl?name=channsgpsc GET text/xml https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/w3query.pl?tablehead=name=heasarc_channsgpsc&Action=More+Options&Action=Parameter+Search&ConeAdd=1 CHANDRA 0.0166666666666667 X-ray public channsgpsc Chandra Nearby Spiral Galaxies Point Source Catalog galaxy_name Galaxy Designation char nullable name Source identification meta.id;meta.main char nullable ra Right Ascension degree pos.eq.ra;meta.main double nullable dec Declination degree pos.eq.dec;meta.main double nullable hb_counts_1 First Observation 2.0-8.0 keV Counts ct float nullable hb_counts_1_error Error in First Observation 2.0-8.0 keV Counts ct float nullable lx_1 First Observation 0.3-8.0 keV Power Law Luminosity (erg/s) erg/s double nullable lx_1_error Error in First Observation 0.3-8.0 keV Power Law Luminosity (erg/s) erg/s float nullable bii Galactic Latitude degree pos.galactic.lat double nullable fb_counts_2 Second Observation 0.3-8.0 keV Counts ct double nullable fb_counts_2_flag Flag on Second Observation 0.3-8.0 keV Counts char nullable lx_1_flag Flag on First Observation 0.3-8.0 keV Power Law Luminosity char nullable fb_counts_1 First Observation 0.3-8.0 keV Counts ct double nullable hard_color_2_neg_err Lower Limit Error for Second Observation Hard Color float nullable flux_2 Second Observation 0.3-8.0 keV Power Law Flux (erg/s/cm^2) erg/s/cm^2 double nullable flux_1_flag Flag on First Observation 0.3-8.0 keV Power Law Flux char nullable hard_color_1 First Observation Hard Color float nullable mb_counts_1_flag Flag on First Observation 1.0-2.0 keV Counts char nullable notes Additional Notes, Alternate Source Names from Literature, CCD (If Not S3) char nullable hb_counts_2 Second Observation 2.0-8.0 keV Counts ct float nullable mb_counts_1 First Observation 1.0-2.0 keV Counts ct float nullable hard_color_2_pos_err Upper Limit Error for Second Observation Hard Color float nullable mb_counts_2_flag Flag on Second Observation 1.0-2.0 keV Counts char nullable sb_counts_2_flag Flag on Second Observation 0.3-1.0 keV Counts char nullable mb_counts_2 Second Observation 1.0-2.0 keV Counts ct float nullable mb_counts_1_error Error in First Observation 1.0-2.0 keV Counts ct float nullable soft_color_2_pos_err Upper Limit Error for Second Observation Soft Color float nullable mb_counts_2_error Error in Second Observation 1.0-2.0 keV Counts ct float nullable soft_color_2_neg_err Lower Limit Error for Second Observation Soft Color float nullable sb_counts_2_error Error in Second Observation 0.3-1.0 keV Counts ct float nullable hard_color_1_pos_err Upper Limit Error for First Observation Hard Color float nullable flux_1 First Observation 0.3-8.0 keV Power Law Flux (erg/s/cm^2) erg/s/cm^2 double nullable lx_2_flag Flag for Second Observation 0.3-8.0 keV Power Law Luminosity char nullable lii Galactic Longitude degree pos.galactic.lon double nullable hb_counts_1_flag Flag on First Observation 2.0-8.0 keV Counts char nullable hard_color_1_neg_err Lower Limit Error for First Observation Hard Color float nullable fb_counts_1_flag Flag on First Observation 0.3-8.0 keV Counts char nullable soft_color_1_pos_err Upper Limit Error for First Observation Soft Color float nullable hb_counts_2_error Error in Second Observation 2.0-8.0 keV Counts ct float nullable soft_color_1 First Observation Soft Color float nullable variability_flag Flag Indicates Variability char nullable flux_2_flag Flag for Second Observation 0.3-8.0 keV Power Law Flux char nullable sb_counts_1_flag Flag on First Observation 0.3-1.0 keV Counts char nullable flux_2_error Error in Second Observation 0.3-8.0 keV Power Law Flux (erg/s/cm^2) erg/s/cm^2 double nullable sb_counts_1 First Observation 0.3-1.0 keV Counts ct float nullable hb_counts_2_flag Flag on Second Observation 2.0-8.0 keV Counts char nullable sb_counts_1_error Error in First Observation 0.3-1.0 keV Counts ct float nullable flux_1_error Error in First Observation 0.3-8.0 keV Power Law Flux (erg/s/cm^2) erg/s/cm^2 double nullable fb_counts_1_error Error in First Observation 0.3-8.0 keV Counts ct float nullable sb_counts_2 Second Observation 0.3-1.0 keV Counts ct double nullable fb_counts_2_error Error in Second Observation 0.3-8.0 keV Counts ct float nullable hard_color_2 Second Observation Hard Color float nullable soft_color_2 Second Observation Soft Color float nullable lx_2_error Error in Second Observation 0.3-8.0 keV Power Law Luminosity (erg/s) erg/s float nullable soft_color_1_neg_err Lower Limit Error for First Observation Soft Color float nullable lx_2 Second Observation 0.3-8.0 keV Power Law Luminosity (erg/s) erg/s 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