J/ApJ/910/134ivo://CDS.VizieR/J/ApJ/910/134doi:10.26093/cds/vizier.19100134CDSGordon A.C.Aydi E.Page K.L.Li K.-L.Chomiuk L.Sokolovsky K.V.,Mukai K.Seitz J.2022-10-12T12:20:16Z2022-10-10T09:37:39ZCDS support team

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

cds-question@unistra.frnovaegamma-ray-astronomyx-ray-sourcesThe detection of GeV {gamma}-ray emission from Galactic novae by the Fermi-Large Area Telescope has become routine since 2010, and is generally associated with shocks internal to the nova ejecta. These shocks are also expected to heat plasma to ~10^7^K, resulting in detectable X-ray emission. In this paper, we investigate 13 {gamma}-ray emitting novae observed with the Neil Gehrels Swift Observatory, searching for 1-10keV X-ray emission concurrent with {gamma}-ray detections. We also analyze {gamma}-ray observations of novae V407 Lup (2016) and V357 Mus (2018). We find that most novae do eventually show X-ray evidence of hot shocked plasma, but not until the {gamma}-rays have faded below detectability. We suggest that the delayed rise of the X-ray emission is due to large absorbing columns and/or X-ray suppression by corrugated shock fronts. The only nova in our sample with a concurrent X-ray/{gamma}-ray detection is also the only embedded nova (V407 Cyg). This exception supports a scenario where novae with giant companions produce shocks with external circumbinary material and are characterized by lower density environments, in comparison with novae with dwarf companions where shocks occur internal to the dense ejecta.2021ApJ...910..134Ghttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/910/134CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toB/vsx : AAVSO International Variable Star Index VSX (Watson+, 2006-2014)B/swift : Swift Master Catalog (HEASARC, 2004-)J/MNRAS/397/1177 : Swift-XRT observations of GRBs (Evans+, 2009)J/ApJS/197/31 : Swift X-ray obs. of classical novae. II. (Schwarz+, 2011)J/ApJ/734/12 : Survey of novae in M31 (Shafter+, 2011)J/ApJ/788/48 : X-ray through NIR photometry of NGC 2617 (Shappee+, 2014)J/MNRAS/469/4341 : Seven recent novae BVI light curves (Munari+, 2017)J/ApJ/852/108 : Multiwavelength obs. of NOVA Sco 2012 (Finzell+, 2018)J/A+A/639/L10 : VRI photometry of V392 Per (Munari+, 2020)J/ApJS/247/33 : Fermi LAT fourth source catalog (4FGL) (Abdollahi+, 2020)http://www.astrosurf.com/aras/Aras_DataBase/Novae.htm : ARAS spectral databasehttp://fermi.gsfc.nasa.gov/ssc/ : Fermi Science Support Center home pagehttp://www.aavso.org/ : AAVSO home pagehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/910/134https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/910/134http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/910/134https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/910/134https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/910/134http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/910/134GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/910/134/novae (Properties of the {gamma}-ray detected novae (Tables 1 and 2))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/910/134/novae?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/910/134/novae?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/910/134/novae?GETtext/xml+votable180.050000true70.839039247.35718610.0055555555555555566/1807 12910 15372 22247 28730 28765 28783 28786 37214 37335 37862 41713 42630https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/910/134?format=asciiGamma-rayX-raydefaultJ/ApJ/910/134/novaeProperties of the {gamma}-ray detected novae (Tables 1 and 2)MJDend2? Upper range of time {gamma}-ray enddtime.epochintnullableDust?[Y/N] Dust?meta.codecharf_MJDend2Flag on MJDend2 (1)meta.codecharNameName of the novameta.id;meta.maincharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintMJDst[55265/58238] Time {gamma}-ray startdtime.epochintf_MJDstFlag on MJDst (1)meta.codecharMJDend[55287/58246] Time {gamma}-ray enddtime.epochintFGeV[0.4/12.2] Average flux over the energy range of >100MeV1e-07ph.s**-1.cm**-2phot.flux.density;em.gamma.hardfloate_FGeV[0.2/0.9] FGeV uncertainty1e-07ph.s**-1.cm**-2stat.errorfloatInd[1.8/2.42] Photon index (2)spect.indexfloate_Ind[0.02/0.3] Ind uncertaintystat.errorfloatRefReference (3)meta.ref;pos.framecharMJD0[55265.8/58237.5] Modified Julian Date, t0 (4)dtime.epochdoubler_MJD0[1/28] Reference on MJD0 (5)meta.ref;pos.frameintDateYear of first observation in eruption, t0stime.epochr_Date[1/28] Reference on Date (5)meta.ref;pos.frameintl_mag[~<] Limit or uncertainty flag on magmeta.code.errorcharmagDiscovery optical magnitude at t0; V-band unless otherwise notedmagphot.mag;em.optfloatSimbadSimbad column added by the CDSmeta.ref.urlcharf_magFlag on mag (6)meta.codecharr_mag[1/24] Reference on mag (5)meta.refintl_Vmax[~<] Limit or uncertainty flag on Vmaxmeta.code.errorcharVmax? Peak magnitude in the V band (7)magphot.mag;stat.maxfloatnullablef_VmaxFlag on Vmax (6)meta.codecharr_Vmax[2/28] Reference on Vmax (5)meta.ref;pos.frameintr_Dust?[2/28]? Reference on Dust? (5)meta.ref;pos.frameintnullablet2[3/90] Time for the optical light curve to decline by two magnitudes from the maximum (7)dtime.epochfloate_t2[1/5]? t2 uncertaintydstat.errorintnullabler_t2[2/29] Reference on t2 (5)meta.ref;pos.frameintSpClSpectral classification (8)spect.indexcharr_SpCl[2/28] Reference on SpCl (5)meta.ref;pos.frameintFWHM[200/4700] Line Full Width at Half Maximum (8)km/sspect.line.widthinte_FWHM[100/200] FWHM uncertaintykm/sstat.error;phys.angSizeintr_FWHM[2] Reference on FWHM (5)meta.refintl_DistLimit flag on Distmeta.code.errorcharDistDistancekpcpos.distance;pos.heliocentricfloate_Dist[0.4/1.5]? Lower uncertainty on Distkpcstat.errorfloatnullableE_Dist[0.4/2.3]? Upper uncertainty on Distkpcstat.error;stat.maxfloatnullabler_Dist[2/29] Reference on Dist (5)meta.ref;pos.frameintNH[0.6/10.1]? Hydrogen column density (8)1e+21cm**-2phys.columnDensityfloatnullablee_NH[0.1/1.2]? NH uncertainty1e+21cm**-2stat.errorfloatnullabler_NH[2]? Reference on NH (5)meta.ref;pos.frameintnullableLCInteractive LC plotmeta.ref.urlchar_RARight Ascension (J2000) from SIMBAD (not part of the original data)degpos.eq.ra;meta.main_DEDeclination (J2000) from SIMBAD (not part of the original data)degpos.eq.dec;meta.mainJ/ApJ/910/134/xrtlcsXRT light curves for the 13 novae (Figures A1-A13)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameName of the novameta.id;meta.maincharMJD[55268/58952] Modified Julian Date of the observationtime.epochdoubleObsIDObservation identifiermeta.id;obs.param;obscharHardRate[0.0005/5] The 1-10keV ratect/sphot.count;em.X-raydoublee_HardRate[0/0.07] Uncertainty in HardRate (1)ct/sstat.errordoubleSoftRate[0.0005/71] The 0.3-1keV ratect/sphot.count;em.X-raydoublee_SoftRate[0/7] Uncertainty in SoftRate (1)ct/sstat.errordoubleModeObservation mode (2)meta.codechar