J/ApJ/922/155ivo://CDS.VizieR/J/ApJ/922/155doi:10.26093/cds/vizier.19220155CDSMolina M.Reines A.E.Latimer C.J.Baldassare V.Salehirad S.2023-09-27T06:46:36Z2023-04-25T09:35:44ZCDS support team

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

cds-question@unistra.frdwarf-galaxiesactive-galactic-nucleiblack-holesvisible-astronomyspectroscopyThe massive black hole (BH) population in dwarf galaxies (M_BH_<~10^5^M_{sun}_) can provide strong constraints on the origin of BH seeds. However, traditional optical searches for active galactic nuclei (AGNs) only reliably detect high-accretion, relatively high-mass BHs in dwarf galaxies with low amounts of star formation, leaving a large portion of the overall BH population in dwarf galaxies relatively unexplored. Here, we present a sample of 81 dwarf galaxies (M_*_<=3x10^9^M_{sun}_) with detectable [FeX]{lambda}6374 coronal line emission indicative of accretion onto massive BHs, only two of which were previously identified as optical AGNs. We analyze optical spectroscopy from the Sloan Digital Sky Survey and find [FeX]{lambda}6374 luminosities in the range L_[FeX]_~10^36^-10^39^erg/s, with a median value of 1.6x10^38^erg/s. The [FeX]{lambda}6374 luminosities are generally much too high to be produced by stellar sources, including luminous Type IIn supernovae (SNe). Moreover, based on known SNe rates, we expect at most eight Type IIn SNe in our sample. That said, the [FeX]{lambda}6374 luminosities are consistent with accretion onto massive BHs from AGNs or tidal disruption events (TDEs). We find additional indicators of BH accretion in some cases using other emission line diagnostics, optical variability, and X-ray and radio emission (or some combination of these). However, many of the galaxies in our sample only have evidence for a massive BH based on their [FeX]{lambda}6374 luminosities. This work highlights the power of coronal line emission to find BHs in dwarf galaxies missed by other selection techniques and to probe the BH population in bluer, lower-mass dwarf galaxies.2021ApJ...922..155Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/922/155CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toV/154 : Sloan Digital Sky Surveys (SDSS), Release 16 (DR16) (Ahumada+, 2020)J/AcA/50/421 : OGLE-II DIA BUL_SC1 field (Wozniak, 2000)J/ApJ/703/370 : Radio SNRs in nearby galaxies (Chomiuk+, 2009)J/MNRAS/398/1165 : AGN in nearby galaxies (Goulding+, 2009)J/ApJ/698/895 : Variations in QSOs optical flux (Kelly+, 2009)J/MNRAS/412/1419 : Nearby supernova rates (Leaman+, 2011)J/MNRAS/410/166 : Morphological types from Galaxy Zoo 1 (Lintott+, 2011)J/ApJ/733/60 : Accretion rate of AGNs from COSMOS surveys (Trump+, 2011)J/MNRAS/421/1043 : Emission-line galaxies from SDSS DR7 (Shirazi+, 2012)J/ApJ/775/116 : z<0.06 active BH galaxies from SDSS-DR8 (Reines+, 2013)J/MNRAS/450/905 : New SNe in SDSS DR9 (Graur+, 2015)J/ApJ/813/82 : z<0.06 broad-line AGN emission-line measures (Reines+, 2015)J/MNRAS/454/3722 : AGN in nearby low-mass galaxies (Sartori+, 2015)J/MNRAS/467/540 : BASS. IV. NIR lines & X-ray (Lamperti+, 2017)J/ApJ/872/148 : 2MASX/NVSS gal. brighter than K_20fe_=12.25 (Condon+, 2019)J/ApJ/871/193 : Chandra & LAMOST study of stellar activity (He+, 2019)J/A+A/623/A173 : SNe/SNRs in starburst galaxy Arp 220 (Varenius+, 2019)J/ApJ/896/10 : NSA galaxies with long-term PTF obs. (Baldassare+, 2020)J/ApJ/888/36 : SDSS/FIRST galaxies with VLA high res. obs. (Reines+, 2020)J/ApJ/907/17 : HMXB-dominant galaxy sample and properties (Lehmer+, 2021)http://www.nsatlas.org/ : NASA-Sloan Atlas home pagehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/922/155https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/922/155http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/922/155https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/922/155https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/922/155http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/922/155GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/922/155/galaxies (81 [FeX]6374-emitting dwarf galaxies (Table 1) with [FeX]6374 measurements (Table 2) and emission line fluxes (Table 3))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/922/155/galaxies?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/922/155/galaxies?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/922/155/galaxies?GETtext/xml+votable180.050000true146.0078-0.642260.0055555555555555566/4219 4244 4406 4517 4917 5050 5052 5133 5376 5512 5541 5556 5905 6453 6576 7186 7240 7315 7340 7353 7511 7518 8478 8583 8833 8843 8927 9010 9120 9601 9859 10393 10459 10462 10482 10502 10544 10638 10806 10815 10823 10883 11041 11121 11187 11191 11338 11355 11876 16887 17238 18002 18831 19756 23186-23187 23202 23207 23212 25839 26206 26363 26611 26958 27199 27494 27600 27635 27697 27841 27917 28391 28455 28597 30037 31400 31403 31725 31736 49093https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/922/155?format=asciiOpticaldefaultJ/ApJ/922/155/galaxies81 [FeX]6374-emitting dwarf galaxies (Table 1) with [FeX]6374 measurements (Table 2) and emission line fluxes (Table 3)Sep[0.02/3] Distance between galaxy center and SDSS fiberarcsecpos.angDistancefloatz[0.002/0.15] Redshift (1)src.redshiftdoubleMass[7.5/9.7] Log of the stellar mass (1) (2)log(solMass)phys.massfloatSFR[0.01/7.6]? Star Formation Rate (3)solMass/yrphys.SFRfloatnullableMetal[7.7/8.6] Metallicity (4)phys.abund.ZfloatClassClassification from previous study (6)src.classcharFFeX[2.4/40] Emission-line [FeX]6374{AA} flux; in 10^-17^erg/s/cm^2^1e-20W.m**-2phot.fluxfloate_FFeX[1/10.4] Error on FeX-flx1e-20W.m**-2stat.errorfloatLFeX[36/39.6] Log of emission-line [FeX]6374{AA} luminosity in erg/slog(1e-07W)phys.luminosityfloate_LFeX[0.3/1] Error on FeX-lumlog(1e-07W)stat.errorfloatsigPk[2/11.1] Comparison of [FeX] peak to residual continuum, {sigma}_peak_stat.fit.residualfloatS/N[2/9.5] Signal-to-noise of the emission-line flux, S/N_line_stat.snr;phot.fluxfloatFeXg/sn[0.1/165.4] Comparison of [FeX] emission in galaxy to SN2005ip, L([FeX])_gal_/L([FeX])_SN2005ip_) (7)phys.luminosity;arith.ratiofloatFHeII4686[4/100]? HeII4686{AA} emission-line flux (8)1e-20W.m**-2phot.fluxintnullablee_FHeII4686[2/10]? Error on HeII4686-flx1e-20W.m**-2stat.errorintnullableFHbeta-n[6/7270] H{beta} 4861{AA} narrow emission-line flux (8)1e-20W.m**-2phot.fluxinte_FHbeta-n[1/100] Error on Hbeta-n-flx1e-20W.m**-2stat.errorintFHbeta-b[360/360]? H{beta} 4861{AA} broad emission-line flux (8)1e-20W.m**-2phot.fluxintnullablee_FHbeta-b[30/30]? Error on Hbeta-b-flx1e-20W.m**-2stat.errorintnullableFOIII5007[8/38100] Forbidden [OIII]5007{AA} emission-line flux (8)1e-20W.m**-2phot.fluxinte_FOIII5007[2/10000] Error on OIII5007-flx1e-20W.m**-2stat.errorintFOI6300[5/460] Forbidden [OI]6300{AA} emission-line flux (8)1e-20W.m**-2phot.fluxinte_FOI6300[1/30] Error on OI6300-flx1e-20W.m**-2stat.errorintFHalpha-n[19/29400] H{alpha} 6563 narrow emission-line flux (8)1e-20W.m**-2phot.fluxinte_FHalpha-n[1/2000] Error on Halpha-n-flx1e-20W.m**-2stat.errorintFHalpha-b[30/2520]? H{alpha} 6563 broad emission-line flux (8)1e-20W.m**-2phot.fluxintnullablee_FHalpha-b[10/50]? Error on Halpha-b-flx1e-20W.m**-2stat.errorintnullableFNII6583[2/2613] Forbidden [NII]6583{AA} emission-line flux (8)1e-20W.m**-2phot.fluxinte_FNII6583[1/10] Error on NII6583-flx1e-20W.m**-2stat.errorinte_FOII7320[2/9]? Error on OII7320-flx1e-20W.m**-2stat.errorintnullableFOIII7330[3/161]? Forbidden [OII]7330{AA} emission-line flux (8)1e-20W.m**-2phot.fluxintnullablee_FOIII7330[1/8]? Error on OII7330-flx1e-20W.m**-2stat.errorintnullableSloanDisplay the online SDSS-DR16 data for the nearest objectmeta.ref.urlcharRefReference of previous study (5)meta.ref;pos.framecharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintFOII7320[4/200]? Forbidden [OII]7320{AA} emission-line flux (8)1e-20W.m**-2phot.fluxintnullableSimbadNameSimbad column added by the CDSmeta.idcharnullableNEDNED column added by the CDSmeta.ref.urlcharLEDAmeta.ref.urlcharNSAID[50/670127] NASA-Sloan Atlas (NSA) identification number (1)meta.id;meta.mainintRAJ2000[8/343.2] Right Ascension of galaxy center (J2000) (1)degpos.eq.ra;meta.mainDEJ2000[-11.2/68.2] Declination of galaxy center (J2000) (1)degpos.eq.dec;meta.mainRASdeg[8/343.2] Right Ascension of SDSS fiber (J2000) (1)degpos.eq.raDESdeg[-11.2/68.2] Declination of SDSS fiber (J2000) (1)degpos.eq.decFSII6716[4/1660] Forbidden [SII]6716{AA} emission-line flux (8)1e-20W.m**-2phot.fluxinte_FSII6716[1/80] Error on SII6716-flx1e-20W.m**-2stat.errorintFSII6731[6/1380] Forbidden [SII]6731{AA} emission-line flux (8)1e-20W.m**-2phot.fluxinte_FSII6731[1/80] Error on SII6731-flx1e-20W.m**-2stat.errorint