J/A+A/611/A95ivo://CDS.VizieR/J/A+A/611/A95doi:10.26093/cds/vizier.36110095CDSWeilbacher P.M.Monreal-Ibero A.Verhamme A.Sandin C.Steinmetz M.,Kollatschny W.Krajnovic D.Kamann S.Roth M.M.Erroz-Ferrer S.,Marino R.A.Maseda M.V.Wendt M.Bacon R.Dreizler S.Richard J.,Wisotzki L.2018-05-16T08:10:35Z2018-04-12T07:50:01ZCDS support team

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

cds-question@unistra.frgalaxiesvisible-astronomyh-ii-regionsinterstellar-mediumspectroscopydiffuse-molecular-cloudsnarrow-band-photometryatomic-spectroscopyThe Antennae galaxy (NGC 4038/39) is the closest major interacting galaxy system and is therefore often studied as a merger prototype. We present the first comprehensive integral field spectroscopic dataset of this system, observed with the MUSE instrument at the ESO VLT. We cover the two regions in this system which exhibit recent star formation: the central galaxy interaction and a region near the tip of the southern tidal tail. In these fields, we detect HII regions and diffuse ionized gas to unprecedented depth. About 15% of the ionized gas was undetected by previous observing campaigns. This newly detected faint ionized gas is visible everywhere around the central merger, and shows filamentary structure. We estimate diffuse gas fractions of about 60% in the central field and 10% in the southern region. We are able to show that the southern region contains a significantly different population of HII regions, showing fainter luminosities. By comparing HII region luminosities with the HST catalog of young star clusters in the central field, we estimate that there is enough Lyman-continuum leakage in the merger to explain the amount of diffuse ionized gas that we detect. We compare the Lyman-continuum escape fraction of each HII region against emission line ratios that are sensitive to the ionization parameter. While we find no systematic trend between these properties, the most extreme line ratios seem to be strong indicators of density bounded ionization. Extrapolating the Lyman-continuum escape fractions to the southern region, we conclude that simply from the comparison of the young stellar populations to the ionized gas there is no need to invoke other ionization mechanisms than Lyman-continuum leaking HII regions for the diffuse ionized gas in the Antennae.2018A&A...611A..95Whttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/611/A95CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/AJ/127/660 : Photometry in southern tail of the Antennae (Saviane+, 2004)J/ApJS/166/211 : Chandra sources in Antennae galaxies (Zezas+, 2006)J/AJ/140/75 : Antennae galaxies (NGC4038/4039) revisited (Whitmore+, 2010)J/ApJ/750/136 : Molecular clouds in the Antennae from CO(2-1) (Wei+, 2012)J/MNRAS/445/1412 : HII regions and GMC in the Antennae (Zaragoza-Cardiel+ 2014)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/611/A95https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/611/A95http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/611/A95https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/611/A95https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/611/A95http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/611/A95GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/611/A95/list (List of fits images)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/611/A95/list?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/611/A95/list?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/611/A95/list?GETtext/xml+votable180.050000true180.47881-18.880880.0055555555555555566/25344https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/611/A95?format=asciiOpticaldefaultJ/A+A/611/A95/listList of fits imagesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000Right Ascension of center (J2000)degpos.eq.ra;meta.mainDEJ2000Declination of center (J2000)degpos.eq.dec;meta.mainScaleScale of the imagearcsec/pixinstr.scalefloatNxNumber of pixels along X-axismeta.numberintNyNumber of pixels along Y-axismeta.numberintsizeSize of FITS fileKibytephys.size;meta.fitsintFileNameName of FITS file, in subdirectory fitsmeta.id;meta.fitscharTitleTitle of the FITS filemeta.title;meta.fitscharJ/A+A/611/A95/centerHII measurements, centerrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintID? MUSE ID of the HII region (ID)meta.id;obs.fieldintnullableXpeak? Peak in x pixel coordinate (XPEAK)pixpos.cartesian.x;stat.maxintnullableYpeak? Peak in y pixel coordinate (YPEAK)pixpos.cartesian.y;stat.maxintnullableNpix? Number of MUSE pixels in HII region (NPIX)meta.numberintnullableHaObserved integrated line flux (HALPHA)mW.m**-2phot.flux;spect.linedoublee_HaError estimate of Ha (E_HALPHA)mW.m**-2stat.errordoubleHbObserved integrated line flux (HBETA)mW.m**-2phot.flux;spect.linedoublee_HbError estimate of Hb (E_HBETA)mW.m**-2stat.errordoubleOIII5007? OIII5007{AA} observed integrated line flux (OIII5007)mW.m**-2phot.flux;spect.linedoublenullablee_OIII5007Error estimate of OIII5007 (E_OIII5007)mW.m**-2stat.errordoubleOI6300OI 6300{AA} observed integrated line flux (OI6300)mW.m**-2phot.flux;spect.linedoublee_OI6300Error estimate of OI6300 (E_OI6300)mW.m**-2stat.errordoubleSII6716SII 6716{AA} observed integrated line flux (SII6716)mW.m**-2phot.flux;spect.linedoublee_SII6716Error estimate of SII6716 (E_SII6716)mW.m**-2stat.errordoubleSII6731SII 6731{AA} observed integrated line flux (SII6731)mW.m**-2phot.flux;spect.linedoublee_SII6731Error estimate of SIII9068 (E_SII6731)mW.m**-2stat.errordoubleSIII9068? SIII 9068{AA} observed integrated line flux (SIII9068)mW.m**-2phot.flux;spect.linedoublenullablee_SIII9068? Error estimate of SIII9068 (E_SIII9068)mW.m**-2stat.errordoublenullableHa/HbBalmer decrement (HA_HB)phot.flux;arith.ratiofloate_Ha/HbError estimate of Balmer decrement (E_HA_HB)stat.error;phys.abundfloatcHbLogarithmic extinction at Hbeta (C_HBETA)phys.absorptionfloatFH1r6563AH1r 6563{AA} Extinction-corrected flux (F_H1r_6563A)mW.m**-2phot.fluxdoublee_FH1r6563AError estimate of FH1r6563A (E_H1r_6563A)mW.m**-2stat.errordoubleFH1r4861AH1r 4861{AA} extinction-corrected flux (F_H1r_4861A)mW.m**-2phot.fluxdoublee_FH1r4861AError estimate of FH1r4861A (E_H1r_4861A)mW.m**-2stat.errordoubleFO35007AO3 5007{AA} extinction-corrected flux (F_O3_5007A)mW.m**-2phot.fluxdoublee_FO35007AError estimate of FO35007A (E_O3_5007A)mW.m**-2stat.errordoubleFO16300AO1 6300{AA} extinction-corrected flux (F_O1_6300A)mW.m**-2phot.fluxdoublee_FO16300AError estimate of FO16300A (E_O1_6300A)mW.m**-2stat.errordoubleFS26716AS2 6716{AA} extinction-corrected flux (F_S2_6716A)mW.m**-2phot.fluxdoublee_FS26716AError estimate of FS26716A (E_S2_6716A)mW.m**-2stat.errordoubleFS26731AS2 6731{AA} extinction-corrected flux (F_S2_6731A)mW.m**-2phot.fluxdoublee_FS26731AError estimate of FS26731A (E_S2_6731A)mW.m**-2stat.errordoubleFS39069AS3 9069{AA} extinction-corrected flux (F_S3_9069A)mW.m**-2phot.fluxdoublee_FS39069A? Error estimate of FS39069A (E_S3_9069A)mW.m**-2stat.errordoublenullableOIII/SIIOIII/SII extinction-corrected emission line ratio (OIII_SII)meta.notefloate_OIII/SII? Error estimate of OIII/SII (E_OIII_SII)stat.errordoublenullableSIII/SIISIII/SII extinction-corrected emission line ratio (SIII_SII)meta.notefloate_SIII/SII? Error estimate of SIII/SII (E_SIII_SII)stat.errorfloatnullableOIII/OIOIII/OI extinction-corrected emission line ratio (OIII_OI)meta.notedoublee_OIII/OI? Error estimate of OIII/OI (E_OIII_OI)stat.errordoublenullableLHaobsObserved Halpha luminosity (LHa_obs)1e-07Wphys.luminosity;em.line.HalphadoubleLHacorExtinction-corrected Halpha luminosity (LHa_cor)1e-07Wphys.luminosity;em.line.HalphadoubleqH0Halpha-based estimate of LyC photon rate (Q_H0)s**-1phot.count;em.X-raydoublee_qH0Error estimate of qH0 (E_Q_H0)s**-1stat.errordoubleNCluster? Number of young HST clusters in HII region (NCluster)meta.numberintnullableNLyCG? GALEV-based estimate of LyC photon rate (NLyC_GALEV)s**-1phot.count;em.X-raycharfescG? GALEV-based LyC escape fraction (fesc_GALEV)stat.fit.paramfloatnullablee_fescG? Error estimate of fescG (E_fesc_GALEV)stat.errorfloatnullableNLyCSB99? SB99-based estimate of LyC photon rate (NLyC_SB99)s**-1phot.count;em.X-raycharfescSB99? SB99-based LyC escape fraction (fesc_SB99)stat.fit.paramfloatnullablee_fescSB99? Error estimate of fescSB99 (E_fesc_SB99)stat.errorfloatnullableJ/A+A/611/A95/southHII measurements, southID? MUSE ID of the HII region (ID)meta.id;obs.fieldintnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintXpeak? Peak in x pixel coordinate (XPEAK)pixpos.cartesian.x;stat.maxintnullableYpeak? Peak in y pixel coordinate (YPEAK)pixpos.cartesian.y;stat.maxintnullableNpix? Number of MUSE pixels in HII region (NPIX)meta.numberintnullableHaObserved integrated line flux (HALPHA)mW.m**-2phot.flux;spect.linedoublee_HaError estimate of Ha (E_HALPHA)mW.m**-2stat.errordoubleHbObserved integrated line flux (HBETA)mW.m**-2phot.flux;spect.linedoublee_HbError estimate of Hb (E_HBETA)mW.m**-2stat.errordoubleOIII5007? OIII5007{AA} observed integrated line flux (OIII5007)mW.m**-2phot.flux;spect.linedoublenullablee_OIII5007Error estimate of OIII5007 (E_OIII5007)mW.m**-2stat.errordoubleOI6300OI 6300{AA} observed integrated line flux (OI6300)mW.m**-2phot.flux;spect.linedoublee_OI6300Error estimate of OI6300 (E_OI6300)mW.m**-2stat.errordoubleSII6716SII 6716{AA} observed integrated line flux (SII6716)mW.m**-2phot.flux;spect.linedoublee_SII6716Error estimate of SII6716 (E_SII6716)mW.m**-2stat.errordoubleSII6731SII 6731{AA} observed integrated line flux (SII6731)mW.m**-2phot.flux;spect.linedoublee_SII6731Error estimate of SIII9068 (E_SII6731)mW.m**-2stat.errordoubleSIII9068? SIII 9068{AA} observed integrated line flux (SIII9068)mW.m**-2phot.flux;spect.linedoublenullablee_SIII9068? Error estimate of SIII9068 (E_SIII9068)mW.m**-2stat.errordoublenullableHa/HbBalmer decrement (HA_HB)phot.flux;arith.ratiofloate_Ha/HbError estimate of Balmer decrement (E_HA_HB)stat.error;phys.abundfloatcHbLogarithmic extinction at Hbeta (C_HBETA)phys.absorptionfloatFH1r6563AH1r 6563{AA} Extinction-corrected flux (F_H1r_6563A)mW.m**-2phot.fluxdoublee_FH1r6563AError estimate of FH1r6563A (E_H1r_6563A)mW.m**-2stat.errordoubleFH1r4861AH1r 4861{AA} extinction-corrected flux (F_H1r_4861A)mW.m**-2phot.fluxdoublee_FH1r4861AError estimate of FH1r4861A (E_H1r_4861A)mW.m**-2stat.errordoubleFO35007AO3 5007{AA} extinction-corrected flux (F_O3_5007A)mW.m**-2phot.fluxdoublee_FO35007AError estimate of FO35007A (E_O3_5007A)mW.m**-2stat.errordoubleFO16300AO1 6300{AA} extinction-corrected flux (F_O1_6300A)mW.m**-2phot.fluxdoublee_FO16300AError estimate of FO16300A (E_O1_6300A)mW.m**-2stat.errordoubleFS26716AS2 6716{AA} extinction-corrected flux (F_S2_6716A)mW.m**-2phot.fluxdoublee_FS26716AError estimate of FS26716A (E_S2_6716A)mW.m**-2stat.errordoubleFS26731AS2 6731{AA} extinction-corrected flux (F_S2_6731A)mW.m**-2phot.fluxdoublee_FS26731AError estimate of FS26731A (E_S2_6731A)mW.m**-2stat.errordoubleFS39069AS3 9069{AA} extinction-corrected flux (F_S3_9069A)mW.m**-2phot.fluxdoublee_FS39069A? Error estimate of FS39069A (E_S3_9069A)mW.m**-2stat.errordoublenullableOIII/SIIOIII/SII extinction-corrected emission line ratio (OIII_SII)meta.notefloate_OIII/SII? Error estimate of OIII/SII (E_OIII_SII)stat.errordoublenullableSIII/SIISIII/SII extinction-corrected emission line ratio (SIII_SII)meta.notefloate_SIII/SII? Error estimate of SIII/SII (E_SIII_SII)stat.errorfloatnullableOIII/OIOIII/OI extinction-corrected emission line ratio (OIII_OI)meta.notedoublee_OIII/OI? Error estimate of OIII/OI (E_OIII_OI)stat.errordoublenullableLHaobsObserved Halpha luminosity (LHa_obs)1e-07Wphys.luminosity;em.line.HalphadoubleLHacorExtinction-corrected Halpha luminosity (LHa_cor)1e-07Wphys.luminosity;em.line.HalphadoubleqH0Halpha-based estimate of LyC photon rate (Q_H0)s**-1phot.count;em.X-raydoublee_qH0Error estimate of qH0 (E_Q_H0)s**-1stat.errordoubleNCluster? Number of young HST clusters in HII region (NCluster)meta.numberintnullableNLyCG? GALEV-based estimate of LyC photon rate (NLyC_GALEV)s**-1phot.count;em.X-raycharfescG? GALEV-based LyC escape fraction (fesc_GALEV)stat.fit.paramfloatnullablee_fescG? Error estimate of fescG (E_fesc_GALEV)stat.errorfloatnullableNLyCSB99? SB99-based estimate of LyC photon rate (NLyC_SB99)s**-1phot.count;em.X-raycharfescSB99? SB99-based LyC escape fraction (fesc_SB99)stat.fit.paramfloatnullablee_fescSB99? Error estimate of fescSB99 (E_fesc_SB99)stat.errorfloatnullable