VLA Lockman Hole 3-GHz Radio Source Catalog VLALHN3GHZ ivo://nasa.heasarc/vlalhn3ghz NASA/GSFC HEASARC Vernstrom et al. 2026-10-02 NASA/GSFC HEASARC help desk heasarc-vo at athena.gsfc.nasa.gov Survey Source This table is from the second of two papers describing the observations and source catalogs derived from sensitive 3-GHz images of the Lockman Hole North using the Karl G. Jansky Very Large Array (VLA). In their paper, the authors describe the reduction and cataloguing process, which yielded an image with 8-arcsecond resolution and instrumental noise of sigma&lt;sub&gt;n&lt;/sub&gt; = 1.01 &micro;Jy/beam (&micro;Jy/beam) rms (before primary beam corrections) and a catalog of 558 sources detected above 5 * sigma&lt;sub&gt;n&lt;/sub&gt;. The authors also include details of how they estimate source spectral indices across the 2-GHz VLA bandwidth, finding a median index of -0.76 +/- 0.04. Stacking of source spectra reveals a flattening of spectral index with decreasing flux density. In the reference paper, the authors present a source count derived from the catalog. They show a traditional count estimate compared with a completely independent estimate made via a P(D) confusion analysis, and find very good agreement. Cross-matches of the catalog with X-ray, optical, infrared, radio, and redshift catalogs are also presented. The X-ray, optical and infrared data, as well as AGN selection criteria allow them to classify 10% as radio-loud AGN, 28% as radio-quiet AGN, and 58% as star-forming galaxies, with only 4% unclassified. Observations were made with the VLA in the C configuration at S band, with a frequency range of 2 to 4GHz, with a total of roughly 50 hours of on-source time in 2012. The HEASARC has converted the radio and IR flux density units from those given in the original table (&micro;Jy and &micro;Jy/beam) to its standard units for radio flux densities (mJy and mJy/beam). This table was created by the HEASARC in April 2017 based on &lt;a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/MNRAS/462/2934"&gt;CDS Catalog J/MNRAS/462/2934&lt;/a&gt; files cat3ghz.dat and catcrx.dat. This is a service provided by NASA HEASARC . 2016MNRAS.462.2934V https://heasarc.gsfc.nasa.gov/W3Browse/all/vlalhn3ghz.html Catalog Research served-by HEASARC TAP https://heasarc.gsfc.nasa.gov/xamin/vo/cone?showoffsets&table=vlalhn3ghz& GET text/xml 180 99999 true 161.49591667 58.84511111 0.0166666666666667 https://heasarc.gsfc.nasa.gov/xamin/vo/tap https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/getvotable.pl?name=vlalhn3ghz GET text/xml https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/w3query.pl?tablehead=name=heasarc_vlalhn3ghz&Action=More+Options&Action=Parameter+Search&ConeAdd=1 RADIO CATALOG 0.0166666666666667 Radio Optical Infrared X-ray public vlalhn3ghz VLA Lockman Hole 3-GHz Radio Source Catalog name IAU Catalog Designation (TV16 JHHMMSSs+DDMMSS) 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 ra_error Uncertainty in Right Ascension s stat.error;pos.eq.ra;meta.main double nullable dec_error Uncertainty in Declination arcsec stat.error;pos.eq.dec;meta.main double nullable int_flux_3_ghz Total Corrected Flux Density mJy phot.flux.density;em.radio.1500-3000MHz double nullable int_flux_3_ghz_error Uncertainty in Total Flux Density mJy stat.error;phot.flux.density;em.radio.1500-3000MHz double nullable spectral_index Spectral Index from 2 to 4GHz spect.index double nullable spectral_index_error Spectral Index Uncertainty stat.error;spect.index double nullable rmag SDSS DR9 r Magnitude (AB) (Ahn et al., 2012ApJS..203...21A, Cat. V/139) mag phot.mag;em.opt.R 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 flux_3_ghz Peak Flux Density mJy/beam phot.flux.density;em.radio.1500-3000MHz double nullable swire_5p8_um_flux Spitzer/SWIRE 5.8um Flux (Lonsdale et al., 2003PASP..115..897L) mJy phot.flux.density;em.IR.4-8um double nullable gmag SDSS DR9 g Magnitude (AB) (Ahn et al., 2012ApJS..203...21A, Cat. V/139) mag phot.mag;em.opt.B double nullable mips_24_um_flux Spitzer/MIPS 24um Flux (Lonsdale et al., 2003PASP..115..897L) mJy phot.flux.density;em.IR.15-30um double nullable minor_axis Fitted Beam-Convolved Minor Axis Size arcsec phys.angSize.sminAxis double nullable swire_8p0_um_flux Spitzer/SWIRE 8.0um Flux (Lonsdale et al., 2003PASP..115..897L) mJy phot.flux.density;em.IR.4-8um double nullable zmag SDSS DR9 z Magnitude (AB) (Ahn et al., 2012ApJS..203...21A, Cat. V/139) mag phot.mag;em.opt double nullable servs_4p5_um_flux Spitzer/SERVS 4.5um Flux (Mauduit et al., 2012PASP..124..714M) mJy phot.flux.density;em.IR.4-8um double nullable hhdr3_350_um_flux Herschel/Hermes DR3 350um Flux (Oliver et al., 2012, Cat. VIII/95) mJy phot.flux.density;em.mm.750-1500GHz double nullable major_axis_error Uncertainty in Major Axis arcsec stat.error;phys.angSize.smajAxis double nullable bii Galactic Latitude degree pos.galactic.lat double nullable minor_axis_de_error Uncertainty in Deconvolved Minor Axis arcsec stat.error;phys.angSize.sminAxis double nullable major_axis Fitted Beam-Convolved Major Axis Size arcsec phys.angSize.smajAxis double nullable redshift Spectroscopic Redshift src.redshift double nullable source_flag Flag [0-4] Indicates Size meta.code;src short nullable lii Galactic Longitude degree pos.galactic.lon double nullable kmag UKIDSS DR9 K Magnitude (Lawrence et al., 2012, Cat. II/314) mag phot.mag;em.IR.K double nullable kpno_gmag KPNO g Magnitude (AB) (Gonzalez-Solares et al., 2011MNRAS.416..927G) mag phot.mag;em.opt.B double nullable major_axis_limit Limit Flag [<] Indicates Axis Is Less Than 2 Sigma Greater Than the Beam meta.code;phys.angSize.smajAxis char nullable flux_20_cm VLA 1.4GHz Flux (Owen & Morrison, 2008, Cat. J/AJ/136/1889) mJy phot.flux.density;em.radio.750-1500MHz double nullable phot_redshift Photometric Redshift src.redshift.phot double nullable hhdr3_500_um_flux Herschel/Hermes DR3 500um Flux (Oliver et al., 2012, Cat. VIII/95) mJy phot.flux.density;em.mm.400-750GHz double nullable snr_3_ghz Signal-to-Noise Ratio stat.snr;phot.flux.density;em.radio.1500-3000MHz double nullable umag SDSS DR9 u Magnitude (AB) (Ahn et al., 2012ApJS..203...21A, Cat. V/139) mag phot.mag;em.opt.U double nullable swire_3p6_um_flux Spitzer/SWIRE 3.6um Flux (Lonsdale et al., 2003PASP..115..897L) mJy phot.flux.density;em.IR.3-4um double nullable minor_axis_de Deconvolved Minor Axis Size arcsec phys.angSize.sminAxis double nullable position_angle Fitted Position Angle degree pos.posAng short nullable kpno_umag KPNO u Magnitude (AB) (Gonzalez-Solares et al., 2011MNRAS.416..927G) mag phot.mag;em.opt.U double nullable pb_atten_factor Primary Beam Correction Factor meta.code double nullable servs_3p6_um_flux Spitzer/SERVS 3.6um Flux (Mauduit et al., 2012PASP..124..714M) mJy phot.flux.density;em.IR.3-4um double nullable nu_eff Effective Frequency in Wide-Band Image GHz em.freq;em.radio.1500-3000MHz double nullable imag SDSS DR9 i Magnitude (AB) (Ahn et al., 2012ApJS..203...21A, Cat. V/139) mag phot.mag;em.opt.I double nullable minor_axis_limit Limit Flag [<] Indicates Axis Is Less Than 2 Sigma Greater Than the Beam meta.code;phys.angSize.sminAxis char nullable hhdr3_250_um_flux Herschel/Hermes DR3 250um Flux (Oliver et al., 2012, Cat. VIII/95) mJy phot.flux.density;em.mm.750-1500GHz double nullable major_axis_de Deconvolved Major Axis Size arcsec phys.angSize.smajAxis double nullable major_axis_de_error Uncertainty in Deconvolved Major Axis arcsec stat.error;phys.angSize.smajAxis double nullable xray_hb_flux Chandra 2.5-8.0keV Flux (Wilkes et al., 2009, Cat. J/ApJS/185/433) erg/s/cm^2 phot.flux;em.X-ray.medium double nullable flux_90_cm VLA 325MHz Flux (Owen et al., Cat. J/AJ/137/4846) mJy phot.flux.density;em.radio.200-400MHz double nullable kpno_rmag KPNO r Magnitude (AB) (Gonzalez-Solares et al., 2011MNRAS.416..927G) mag phot.mag;em.opt.R double nullable kpno_imag KPNO i Magnitude (AB) (Gonzalez-Solares et al., 2011MNRAS.416..927G) mag phot.mag;em.opt.I double nullable swire_4p5_um_flux Spitzer/SWIRE 4.5um Flux (Lonsdale et al., 2003PASP..115..897L) mJy phot.flux.density;em.IR.4-8um double nullable xray_fb_flux Chandra 0.3-8.0keV Flux (Wilkes et al., 2009, Cat. J/ApJS/185/433) erg/s/cm^2 phot.flux;em.X-ray double nullable jmag UKIDSS DR9 J Magnitude (Lawrence et al., 2012, Cat. II/314) mag phot.mag;em.IR.J double nullable minor_axis_error Uncertainty in Minor Axis arcsec stat.error;phys.angSize.sminAxis double nullable