J/ApJS/276/72ivo://CDS.VizieR/J/ApJS/276/72CDSLiu C.Gebhardt K.Mentuch Cooper E.Davis D.Schneider D.P.,Jarvis M.J.Farrow D.J.Finkelstein S.L.Chavez Ortiz O.A.,The HETDEX Collaboration2026-02-16T08:16:22Z2026-02-16T08:36:51ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.fractive-galactic-nucleivisible-astronomyspectroscopysurveysredshiftedline-intensitiesapparent-magnitudeWe present the active galactic nuclei (AGN) catalog from the fourth data release (HDR4) of the Hobby-Eberly Telescope Dark Energy Experiment Survey (HETDEX). HETDEX is an untargeted spectroscopic survey. HDR4 contains 345,874 Integral Field Unit observations from 2017 January to 2023 August covering an effective area of 62.9deg2. With no imaging preselection, our spectroscopic confirmed AGN sample includes low-luminosity AGN, narrow-line AGN, and/or red AGN down to g~25. This catalog has 15,940 AGN across the redshifts of z=0.1~4.6, giving a raw AGN number density of 253.4deg^-2^. Among them, 10,499 (66%) have redshifts either confirmed by line pairs or matched to the Sloan Digital Sky Survey Quasar Catalog. For the remaining 5441 AGN, 2083 are single broad-line AGN candidates, while the remaining 3358 are single intermediate broad-line (full width at half-maximum, FWHM~1200km/s) AGN candidates. A total of 4060 (39%) of the 10,499 redshift-confirmed AGN have emission-line regions 3{sigma} more extended than the image quality, which could be strong outflows blowing into the outskirts of the host galaxies or ionized intergalactic medium.2025ApJS..276...72Lhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJS/276/72CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toI/317 : The PPMXL Catalog (Roeser+ 2010)I/345 : Gaia DR2 (Gaia Collaboration, 2018)VII/289 : SDSS quasar catalog, sixteenth data release (DR16Q) (Lyke+, 2020)I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)J/A+A/457/79 : VIMOS VLT Deep Survey: faint type-1 AGN (Gavignaud+, 2006)J/ApJ/943/177 : HETDEX Public Source Cat. (Version 3.2) (Mentuch Cooper+, 2023)http://hetdex.org/ : HETDEX homepagehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJS/276/72https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJS/276/72http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJS/276/72https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJS/276/72https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJS/276/72http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJS/276/72GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJS/276/72/hdr4 (HETDEX HDR4 AGN catalog)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/276/72/hdr4?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/276/72/hdr4?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/276/72/hdr4?GETtext/xml+votable180.050000true188.1563652.06209190.0055555555555555564/372 623 671 687 692-694 697 707 712 1113-1114 1125-1126 5/1399 1405-1407 1479 1485-1486 1492-1494 1496 2530 2536 2559 2679 2747 2765-2767 2780 2785-2787 2792-2794 2796 2800 2827 2833-2836 2840 2852 2856 2858 2901 3839 4010 4415 4431 4442 4451 4460 4464-4465 4495 4499 4508 4510 4517 4528-4529 4544-4545 6814 6/5561 5563-5564 5566 5582-5583 5590-5591 5594-5595 5602-5606 5609 5614-5615 5617-5619 5905 5907-5908 5910 5913 5915 5936-5937 5939 5948-5949 5980-5981 5988-5989 6025-6026 9853 9855 9941-9944 9949-9951 9956 9958-9959 9966-9967 10024 10026 10112 10114 10126 10148 10152-10154 10231 10708-10709 10711 10726-10727 10731 10735 10967 10971 10973-10975 10983 11031 11037-11039 11053-11055 11057-11059 11124 11128 11137-11139 11180-11182 11188 11192 11204 11208 11252 11276-11277 11285 11290-11291 11293-11295 11329-11331 11348-11350 11352-11354 11364-11366 11368-11370 11412-11414 11416-11418 11428-11430 11436 11612-11613 11776-11778 15355 16044 16046 17653-17655 17657-17659 17695 17717-17719 17721-17723 17760 17762-17763 17766 17772 17774-17775 17786 17798-17799 17801-17803 17844-17846 17848-17850 17864-17866 17973-17975 17977-17979 17989-17991 17993-17995 18036-18038 18064-18065 18067 18073-18077 18079 18120-18122 18184-18186 19033 19036 27245 27247 27344https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJS/276/72?format=asciiOpticaldefaultJ/ApJS/276/72/hdr4HETDEX HDR4 AGN catalogrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeq[0/15939] Running sequence number (agnid)meta.id;meta.mainintEWCIII[-3.9/1.8e+15]? Rest-frame EW of the CIII emission (ew_CIII)0.1nmspect.line.eqWidthdoublenullableFMgII[0/6738]? Rest-frame flux of the MgII]{lambda}2799 emission (flux_MgII)1e-17mW.m**-2phot.fluxdoublenullableSNRMgII[-99/155]? SNR of MgII (snr_MgII)stat.snrdoublenullableFWHMMgII[0/10663]? Rest-frame FWHM of the MgII emission (fwhm_MgII)km.s**-1spect.line.widthdoublenullableEWMgII[-8.2/9999]? Rest-frame EW of the MgII emission (ew_MgII)0.1nmspect.line.eqWidthdoublenullableFOVI[0/7587]? Rest-frame flux of the OVI{lambda}1034 emission (flux_OVI)1e-17mW.m**-2phot.fluxdoublenullableSimbadSimbad column added by the CDSmeta.ref.urlcharRAJ2000[5.9/335.1] FoF center right ascension (J2000) (ra) (1)degpos.eq.ra;meta.mainindexedDEJ2000[-2.5/68] FoF center declination (J2000) (dec) (1)degpos.eq.dec;meta.mainindexedz[0.085/4.61] Redshift (z)src.redshiftdoublee_z[0/0.009] z uncertainty (z_err)stat.error;src.redshiftdoublef_z[0/1] Flag on z (1=confirmed z) (zflag)meta.codeintf_Seq[0/1] Flag on Seq (1=confirmed AGN) (agn_flag)meta.codeintMeth[0/3]? Method flag (sflag) (2)meta.codeintnullableNshot[0/15] Number of the observed shots of (R.A., decl.) (nshot)meta.numberintNmem[1/96] Number of member detectids (nmem)meta.numberintBestDet[3000035705/4090574155] Detectid closest to the FoF center (detectid_best)meta.idRABdegRight ascension (J2000) of BestDet (ra_best) (3)degpos.eq.raDEBdegDeclination (J2000) of BestDet (dec_best) (3)degpos.eq.decroff[0/2.2] Offset between RABdeg,DEBdeg with FoF center (roff)arcsecpos;arith.diffdoublegmag[16.3/32.5] HETDEX g-band magnitude measured at RABdeg,DEBdeg (mag_g_wide) (4)magphot.mag;em.opt.Bfloate_gmag[0/999]? Uncertainty on gmag (mag_g_wide_err) (4)magstat.error;phot.mag;em.opt.BdoublenullablefiberidID of the fiber that is closest to BestDet (fiberid)meta.idcharshotid[20170126002/20230826016] ID of the shot for BestDet (shotid)meta.idmultiframeIFU for BestDet (multiframe)meta.idcharTghPut[0.08/0.6] Throughput of shotid (throughput) (5)stat.fit.paramfloatFWHM-virus[1.2/3.2] Image quality (FWHM) of shotid (fwhm_virus)arcsecinstr.det.psfdoublee_FWHM-virus[0/0.99] FWHM-virus uncertainty (fwhm_virus_err)arcsecstat.error;instr.det.psfdoubleapcor[-99/0.99] Aperture correction of BestDet (a value of 1 means no correction) (apcor)phot.mag;arith.difffloatLamObsElix[3476.6/5530.6] Observed line wavelength fit by ELIXER (wobs_elixer)0.1nmem.wlfloate_LamObsElix[0/11.4] LamObsElix uncertainty (wobs_err_elixer)0.1nmstat.errordoubleFLya[0/17659]? Rest-frame flux of the Lya{lambda}1215 emission (flux_LyA)1e-17mW.m**-2phot.flux;em.line.LyalphadoublenullableSNRLya[0/350]? SNR of Lya (snr_LyA)stat.snr;em.line.LyalphadoublenullableFWHMLya[0/22328]? Rest-frame FWHM of the LyA emission (fwhm_LyA)km.s**-1spect.line.width;em.line.LyalphadoublenullableEWLya[0/28020]? Rest-frame EW of the LyA emission (ew_LyA)0.1nmspect.line.eqWidth;em.line.LyalphadoublenullableFCIV[0/16457]? Rest-frame flux of the CIV{lambda}1549 emission (flux_CIV)1e-17mW.m**-2phot.fluxdoublenullableSNRCIV[-99/226]? SNR of CIV (snr_CIV)stat.snrdoublenullableFWHMCIV[0/19355]? Rest-frame FWHM of the CIV emission (fwhm_CIV)km.s**-1spect.line.widthdoublenullableEWCIV[-449/2.6e+15]? Rest-frame EW of the CIV emission (ew_CIV)0.1nmspect.line.eqWidthdoublenullableFCIII[0/6615]? Rest-frame flux of the CIII]{lambda}1909 emission (flux_CIII)1e-17mW.m**-2phot.fluxdoublenullableSNRCIII[-99/123]? SNR of CIII (snr_CIII)stat.snrdoublenullableFWHMCIII[0/15670]? Rest-frame FWHM of the CIII emission (fwhm_CIII)km.s**-1spect.line.widthdoublenullableSNROVI[-99/233]? SNR of OVI (snr_OVI)stat.snrdoublenullableFWHMOVI[0/29015]? Rest-frame FWHM of the OVI emission (fwhm_OVI)km.s**-1spect.line.widthdoublenullableEWOVI[-36/7.7e+14]? Rest-frame EW of the OVI emission (ew_OVI)0.1nmspect.line.eqWidthdoublenullableLamPipe[3485.8/5530.6]? Observed line wavelength from the HETDEX pipeline (wave_pipe)0.1nmem.wldoublenullableFPipe[0/2071] Observed line flux from the HETDEX pipeline (flux_pipe)1e-17mW.m**-2phot.flux;spect.continuumdoubleContPipe[-12.5/224] Observed continuum from the HETDEX pipeline (continuum_pipe)1e-17cW.m**-2.nm**-1phot.fluxdoublesigmaPipe[0/50] Observed sigma from the pipeline's single Gaussian fit (linewidth_pipe)0.1nmspect.line.widthdoubleSNRPipe[0/186] SNR from the pipeline's single Gaussian fit (sn_pipe)stat.snrdoublechi2Pipe[0/6] Chi2 from the pipeline's single Gaussian fit (chi2_pipe)stat.fit.chi2doublechi2fibPipe[0/9.8] Chi2 of fit to 2D spectrum for each fiber (>4 usually indicates issues) (chi2fib_pipe)stat.fit.chi2doubleSepDR16Q[0.01/3.5]? Separation between the matched SDSS DR16Q AGN (rsep_dr16q)arcsecpos.angDistancefloatnullablezDR16Q[0.08/6.4]? Redshift of the matched SDSS DR16Q AGN (z_dr16q)src.redshiftdoublenullableSDSSSDSS DR16Q AGN identifier (HHMMSS.ss+DDMMSS.s; J2000) (sdssid_dr16q)meta.id.crosscharf_SDSS[0/1] Flag on SDSS (0=not in SDSS DR16Q) (sdss_flag)meta.codeintSloanDisplay the online SDSS-DR18 data for the nearest objectmeta.ref.urlcharFieldField name in the HETDEX survey (field)meta.id;obs.fieldchar