VLAM31325M ivo://nasa.heasarc/vlam31325m NASA/GSFC HEASARC Gelfand et al. 2026-07-17 NASA/GSFC HEASARC help desk heasarc-vo at athena.gsfc.nasa.gov Survey Source This table contains some of the results from a 325-MHz radio survey of M 31, conducted with the A configuration of the Very Large Array. The survey covered an area of 7.6 square degrees, and a total of 405 radio sources between <~ 6" and 170" in extent were mapped with a resolution of 6" and a 1-sigma sensitivity of ~ 0.6mJy/beam. For each source, its morphological class, major axis theta<sub>M</sub>, minor axis theta<sub>m</sub>, position angle theta<sub>PA</sub>, peak flux I, integrated flux density S, spectral index alpha, and spectral curvature parameter {phi were calculated. A comparison of the flux and radial distribution - both in the plane of the sky and in the plane of M 31 - of these sources with those of the XMM-Newton Large-Scale Structure Survey and the Westerbork Northern Sky Survey revealed that a vast majority of sources detected are background radio galaxies. As a result of this analysis, the authors expect that only a few sources are intrinsic to M 31. This study is based on a 5 hr (4 hr on-source) observation of M 31 conducted on 2000 December 15 with the VLA in A configuration. The procedures used to generate the source list and the source properties (essentially making use of the MIRIAD task SFIND) are discussed in Sections 2.2.2 and 2.3 of the reference paper, respectively. This table was created by the HEASARC in September 2014 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJS/155/89">CDS Catalog J/ApJS/155/89</a> file table3.dat, the GLG (Gelfand, Lazio, Gaensler) source list. This is a service provided by NASA HEASARC . 2004ApJS..155...89G https://heasarc.gsfc.nasa.gov/W3Browse/all/vlam31325m.html Catalog Research served-by HEASARC TAP https://heasarc.gsfc.nasa.gov/xamin/vo/cone?showoffsets&table=vlam31325m& GET text/xml 180 99999 true 10.17916667 39.85066944 0.0333333333333333 https://heasarc.gsfc.nasa.gov/xamin/vo/tap https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/getvotable.pl?name=vlam31325m GET text/xml https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/w3query.pl?tablehead=name=heasarc_vlam31325m&Action=More+Options&Action=Parameter+Search&ConeAdd=1 RADIO CATALOG 0.0333333333333333 Radio public vlam31325m VLA M 31 325-MHz Source Catalog name Source Designation 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 flux_325_mhz Peak Brightness at 325MHz mJy/beam phot.flux.density;em.radio.200-400MHz double nullable flux_325_mhz_error Error in Peak Brightness at 325MHz mJy/beam stat.error;phot.flux.density;em.radio.200-400MHz double nullable int_flux_325_mhz Integrated Flux Density at 325MHz mJy phot.flux.density;em.radio.200-400MHz double nullable int_flux_325_mhz_error Error in Integrated Flux Density at 325MHz mJy stat.error;phot.flux.density;em.radio.200-400MHz double nullable rms_325_mhz RMS of the Flux Density around the Source mJy stat.error;phot.flux.density;em.radio.200-400MHz double nullable major_axis Source Major Axis arcsec phys.angSize.smajAxis double nullable spectral_curvature Spectral Curvature Parameter (Phi) spect.index;em.radio double nullable spectral_curvature_error Error in Phi stat.error;spect.index;em.radio double nullable spectral_index_limit Limit Flag for Radio Spectral Index meta.code;spect.index;em.radio char nullable minor_axis Source Minor Axis arcsec phys.angSize.sminAxis double nullable spectral_index_error Error in Radio Spectral Index stat.error;spect.index;em.radio double nullable bii Galactic Latitude degree pos.galactic.lat double nullable position_angle_error Error in Position Angle degree stat.error;pos.posAng short nullable source_type Morphological Category src.class char nullable angular_radius Angular Distance from the Center of M31 arcmin pos.angDistance double nullable position_angle Position Angle degree pos.posAng short nullable projected_radius Projected Radius of Source in M31 kpc pos.distance double nullable lii Galactic Longitude degree pos.galactic.lon double nullable ra_error Error in Right Ascension arcsec stat.error;pos.eq.ra;meta.main double nullable dec_error Error in Declination arcsec stat.error;pos.eq.dec;meta.main double nullable source_number Sequential Identification Number for Each Source in Catalog meta.id;src short nullable minor_axis_error Error in Source Minor Axis arcsec stat.error;phys.angSize.sminAxis double nullable major_axis_error Error in Source Major Axis arcsec stat.error;phys.angSize.smajAxis double nullable spectral_index Radio Spectral Index spect.index;em.radio 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