J/MNRAS/444/757ivo://CDS.VizieR/J/MNRAS/444/757doi:10.26093/cds/vizier.74440757CDSKhramtsova M.S.Wiebe D.S.Lozinskaya T.A.Egorov O.V.2024-08-14T20:18:02Z2015-09-03T12:47:41ZCDS support team

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

cds-question@unistra.frgalaxiesh-ii-regionsinterstellar-mediuminfrared-photometryspectroscopyWe present an analysis of optical spectroscopy and infrared aperture photometry of more than 100 HII complexes in nine galaxies. Spectra obtained with the 6-m telescope of Special Astrophysical Observatory of the Russian Academy of Sciences are used along with archival data from Spitzer and several ground-based telescopes to infer a strength of polycyclic aromatic hydrocarbon (PAH) emission, age, properties of the UV radiation field, and metallicity of studied HII complexes. Physical properties (age, radiation field parameters, metallicity) are related to the F_8_/F_24_ ratio used as a proxy for the PAH abundance in order to reveal factors that may influence the PAH evolution in HII complexes. The well-known correlation between the F_8_/F_24_ ratio and metallicity is confirmed in the studied complexes. The infrared flux ratio also correlates with the [Oiii]{lambda}5007/H{beta} ratio which is often considered as an indicator of the radiation field hardness, but this correlation seems to be a mere reflection of a correlation between [Oiii]{lambda}5007/H{beta} and metallicity. In separate metallicity bins, the F_8_/F_24_ ratio is found to correlate with an age of an Hii complex, which is estimated from the equivalent width of H{beta} line. The correlation is positive for low-metallicity complexes and negative for high-metallicity complexes. Analysing various mechanisms of PAH formation and destruction in the context of found correlations, we suggest that PAH abundance is likely altered by the UV radiation within HII complexes, but this is not necessarily due to their destruction. If PAHs can also form in Hii complexes due to some processes like aromatization, photodestruction, shattering and sputtering of very small grains, the net F_8_/F_24_ ratio is determined by a balance between all these processes that can be different at different metallicities.2014MNRAS.444..757Khttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/444/757CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/444/757https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/444/757http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/444/757https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/444/757https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/444/757http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/444/757GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/444/757/table1 (Summary of galaxies included in the work)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/444/757/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/444/757/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/444/757/table1?GETtext/xml+votable180.050000true26.874541727.333350.005555555555555556Cone search capability for table J/MNRAS/444/757/table2 (List of studied HII complexes in galaxies IC 1727 and NGC 7741 and results of spectroscopy of HII complexes)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/444/757/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/444/757/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/444/757/table2?GETtext/xml+votable180.050000true26.875083327.32516670.005555555555555556Cone search capability for table J/MNRAS/444/757/complexes (Results of aperture IR photometry of HII complexes (table4) and edrived parameters (table5))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/444/757/complexes?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/444/757/complexes?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/444/757/complexes?GETtext/xml+votable180.050000true26.8797527.327330560.0055555555555555566/2121 2320 5715 7624 7799 15592-15593 18398 20270 383906.772611666688002e-21 6.185923063528282e-20https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/444/757?format=asciiOpticalInfrareddefaultJ/MNRAS/444/757/table1Summary of galaxies included in the workrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintGalaxyGalaxy namemeta.id;meta.maincharprimaryN[6/21] Number of studied HII complexesmeta.numberintN2[10/11]? Number of HII complexes in table2meta.numberintnullableDist[3.4/15.1] Adopted distanceMpcpos.distance;pos.heliocentricfloatr_DistDistance reference (1)meta.ref;pos.frameintMTypeMorphological typesrc.morph.typecharr_MTypeMorphological type reference (1)meta.notecharSimbadSimbad column added by the CDSmeta.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/MNRAS/444/757/table2List of studied HII complexes in galaxies IC 1727 and NGC 7741 and results of spectroscopy of HII complexesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintGalaxyGalaxy namemeta.id.parentcharComplexDesignation of complexmeta.id;meta.maincharoRAOffset in right ascension (from the galaxy)arcsecpos.eq.ra;arith.difffloatoDEOffset in declination (from the galaxy)arcsecpos.eq.dec;arith.difffloatI(3728)[2.2/5.2] Bright line intensity of [OII] {lambda}3727+3729 normalized to H{beta}spect.line.intensity;arith.ratiofloate_I(3728)[0.1/1.2] rms uncertainty on I(3728)stat.errorfloatI(4959)[0.1/1.5] Bright line intensity of [OIII] {lambda}4959 normalized to H{beta}spect.line.intensity;em.line.OIII;arith.ratiofloate_I(4959)[0.01/0.12] rms uncertainty on I([OIII])1stat.errorfloatI(5007)[0.19/4.20] Bright line intensity of [OIII] {lambda}5007 normalized to H{beta}spect.line.intensity;em.line.OIII;arith.ratiofloate_I(5007)[0.01/0.11] rms uncertainty on I([OIII])2stat.errorfloatI(Ha)[2.7/3.1] Bright line intensities of H{alpha} normalized to H{beta}meta.notefloate_I(Ha)[0.02/0.15] rms uncertainty on I(Ha)stat.errorfloatI([NII])[0.17/0.82] Bright line intensity of [NII]{lambda}6548+6584 normalized to H{beta}spect.line.intensity;arith.ratiofloate_I([NII])[0.02/0.22] rms uncertainty on I([NII])stat.errorfloatI([SII])[0.42/1.14] Bright line intensity or [SII] {lambda}6717+6731 normalized to H{beta}spect.line.intensityfloate_I([SII])[0.03/0.37] rms uncertainty on I([SII])stat.errorfloatEWHb[4/130] H{beta} equivalent width0.1nmspect.line.eqWidth;em.line.Hbetafloate_EWHb[0.1/2.5] rms uncertainty on EWHb0.1nmstat.errorfloatE(B-V)[0.04/0.39] Redenningmagphot.color.excessfloate_E(B-V)[0.01/0.19] rms uncertainty on E(B-V)magstat.errorfloatAb(O)[7.9/8.5] Abundance 12+log(O/H), estimated by the ONS method (G1)phys.abundfloate_Ab(O)[0.03/0.13] rms uncertainty on Ab(O)stat.errorfloatr/R25[0.1/0.8] Radial distance from the centre of a galaxy normalized to a R_25_pos.distancefloat_RAPosition computed from offsets (right ascension part)degpos.eq.ra;meta.main_DEPosition computed from offsets (declination part)degpos.eq.dec;meta.mainJ/MNRAS/444/757/complexesResults of aperture IR photometry of HII complexes (table4) and edrived parameters (table5)DEJ2000Declination (J2000)pos.eq.dec;meta.mainrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintGalaxyGalaxy namemeta.id.parentcharComplexDesignation of complexmeta.id;meta.maincharRAJ2000Rigth ascension (J2000)pos.eq.ra;meta.mainAp[4/14] Aperture radiusarcsecphys.angSizefloatF3.6Spitzer/IRAC flux at 3.6ummJyphot.mag;em.IR.3-4umfloate_F3.6rms uncertainty on F3.6ummJystat.errorfloatF4.5Spitzer/IRAC flux at 4.5ummJyphot.mag;em.IR.4-8umfloate_F4.5rms uncertainty on F4.5ummJystat.errorfloatF5.8Spitzer/IRAC flux at 5.8ummJyphot.flux.density;em.IR.4-8umfloate_F5.8rms uncertainty on F5.8ummJystat.errorfloatF8.0Spitzer/IRAC flux at 8.0ummJyphot.flux.density;em.IR.8-15umfloate_F8.0rms uncertainty on F8.0ummJystat.errorfloatF8.0ePAH emission at 8.0um (1)mJyphot.flux.density;em.IR.8-15umfloate_F8.0erms uncertainty on F24emJystat.errorfloatF24Spitzer/MIPS flux at 24ummJyphot.flux.density;em.IR.15-30umfloate_F24rms uncertainty on F24ummJystat.errorfloatF24ePAH emission at 24ummJyphot.flux.density;em.IR.15-30umfloate_F24erms uncertainty on F24emJystat.errorfloatAge[0.1/8.6] AgeMyrtime.agefloatnullablee_Age[0.01/1.1] rms uncertainty on AgeMyrstat.error;time.agefloatnullableAb(O)[7.4/9] Abundance 12+log(O/H) (G1)phys.abundfloatnullablee_Ab(O)[0.01/0.15] rms uncertainty on Ab(O)stat.errorfloatnullableI(5007)[0/5] Ratio [OIII]{lambda}5007/H{beta} considered as a potential indicator of the radiation field hardnessphys.absorption;em.line.OIII;obs.fieldfloatnullablee_I(5007)rms uncertainty on I(5007)stat.errorfloatnullable