J/A+A/617/A130ivo://CDS.VizieR/J/A+A/617/A130doi:10.26093/cds/vizier.36170130CDSInami H.Armus L.Matsuhara H.Charmandaris V.Diaz-Santos T.,Surace J.Stierwalt S.Ohyama Y.Howell J.Marshall J.Evans A.S.,Linden S.T.Mazzarella J.2018-10-05T09:28:27Z2018-10-02T08:45:25ZCDS support team

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

cds-question@unistra.frgalaxiesinfrared-sourcesline-intensitiesinfrared-astronomyspectroscopyWe present AKARI 2.5-5um spectra of 145 local luminous infrared galaxies (LIRG; L_IR_>=10^11^L_{sun}_) in the Great Observatories All-sky LIRG Survey (GOALS). In all of the spectra, we measure the line fluxes and equivalent widths (EQWs) of the polycyclic aromatic hydrocarbon (PAH) at 3.3um and the hydrogen recombination line Br{alpha} at 4.05um, with apertures matched to the slit sizes of the Spitzer low-resolution spectrograph and with an aperture covering ~95% of the total flux in the AKARI two-dimensional (2D) spectra. The star formation rates (SFRs) derived from the Br{alpha} emission measured in the latter aperture agree well with SFRs estimated from LIR, when the dust extinction correction is adopted based on the 9.7um silicate absorption feature. Together with the Spitzer Infrared Spectrograph (IRS) 5.2-38um spectra, we are able to compare the emission of the PAH features detected at 3.3um and 6.2um. These are the two most commonly used near/mid-infrared indicators of starburst or active galactic nucleus (AGN) dominated galaxies. We find that the 3.3um and 6.2um PAH EQWs do not follow a linear correlation and at least a third of the galaxies classified as AGN-dominated sources using the 3.3um feature are classified as starbursts based on the 6.2um feature. These galaxies have a bluer continuum slope than galaxies that are indicated to be starburst-dominated by both PAH features. The bluer continuum emission suggests that their continuum is dominated by stellar emission rather than hot dust. We also find that the median Spitzer/IRS spectra of these sources are remarkably similar to the pure starburst-dominated sources indicated by high PAH EQWs in both 3.3um and 6.2um. Based on these results, we propose a revised starburst/AGN diagnostic diagram using 2-5um data: the 3.3um PAH EQW and the continuum color, F{nu}(4.3um)/F{nu}(2.8um). We use the AKARI and Spitzer spectra to examine the performance of our new starburst/AGN diagnostics and to estimate 3.3um PAH fluxes using the James Webb Space Telescope (JWST) photometric bands in the redshift range 0<z<5. Of the known PAH features and mid-infrared high ionization emission lines used as starburst/AGN indicators, only the 3.3um PAH feature is observable with JWST at z>3.5, because the rest of the features at longer wavelengths fall outside the JWST wavelength coverage.2018A&A...617A.130Ihttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/617/A130CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/ApJS/206/1 : Mid-IR properties of GOALS nearby LIRGs (Stierwalt+, 2013)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/617/A130https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/617/A130http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/617/A130https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/617/A130https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/617/A130http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/617/A130GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/617/A130/table1 (Line flux and equivalent widths of 3.3um PAH and Bra, the continuum color, and EW(6.2um PAH))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/617/A130/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/617/A130/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/617/A130/table1?GETtext/xml+votable180.050000true2.4725511125.923980.0055555555555555566/226 231 295 538 627 650 700 1701 2518 3824 3934 4993 5116 5130 5523 5816 6098 6348 7552 8266 8673 8997 9895 10081 10144 10210 10281 10404 10453 10465 10716 11029 11101 11180 11206 11908 12537 13021 13184 13523 13632 14164 15323 15333 15570 16045 16091 16690 16758 17075 17183 17252 17506 18406 18432 18714 18753 18897 18932 19283 19619 20060-20061 20118 20208 20254 20896 21016 22721 23339 24163 24584 24855 24958 25462 25610 26035 26198 26264 26298 26324 26811 27537 28393 28999 29937 30027 30383 30580 30822 31081 31158 31430 31503 34010 34531 35067 35602 35608 37113 37821 38129 38139 38246 38285 38786 38935 39472 39960 40801 41276 41402 43082 43107 43147 43298 43389 43925 43994 44671 45387 46077 46079 46130 46296 46399 46794 46811 46882 47543 47854https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/617/A130?format=asciiInfrareddefaultJ/A+A/617/A130/sed-agnMedian SED of AGN-dominated LIRGsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintLambdaRest-frame wavelengthumem.wlfloatB_FluxUpper value of the normalized flux densitymJyphot.fluxfloatb_FluxLower value of the normalized flux densitymJyphot.fluxfloatJ/A+A/617/A130/sed-sbMedian SED of starburst-dominated LIRGsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintLambdaRest-frame wavelengthumem.wlfloatB_FluxUpper value of the normalized flux densitymJyphot.fluxfloatb_FluxLower value of the normalized flux densitymJyphot.fluxfloatJ/A+A/617/A130/table1Line flux and equivalent widths of 3.3um PAH and Bra, the continuum color, and EW(6.2um PAH)SimbadNameSimbad column added by the CDSmeta.idcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameObject namemeta.id;meta.maincharTag[*] Note (1)meta.codecharRAJ2000Right Ascension (J2000)degpos.eq.ra;meta.mainDEJ2000Declination (J2000)degpos.eq.dec;meta.mainl_F3.3Upper limit flag on 3.3 micron PAH fluxmeta.code.errorcharF3.3Flux of 3.3 micron PAH1e-16W.m**-2phot.flux.density;em.IR.3-4umfloate_F3.3? Uncertainty of 3.3 micron PAH flux1e-16W.m**-2stat.errorfloatnullablel_EW3.3Limit flag on 3.3 micron PAH EQWmeta.code.errorcharEW3.3Equivalent width of 3.3 micron PAHumspect.line.eqWidthfloate_EW3.3? Uncertainty of 3.3 micron PAH EQWumstat.errorfloatnullablel_FBraUpper limit flag on Bra fluxmeta.code.errorcharFBraFlux of Bra1e-16W.m**-2phot.fluxfloate_FBra? Uncertainty of Bra flux1e-16W.m**-2stat.errorfloatnullablel_EWBraUpper limit flag on Bra EQWmeta.code.errorcharEWBraEquivalent width of Braumspect.line.eqWidthfloate_EWBra? Uncertainty of Bra EQWumstat.errorfloatnullableColorContinuum color of Fnu(4.3um)/Fnu(2.8um)phot.color;em.IR;em.IRfloate_ColorUncertainty of Continuum colorstat.error;phot.colorfloatl_EW6.2Upper limit flag on 6.2 micron PAH EQWmeta.code.errorcharEW6.2? Equivalent width of 6.2 micron PAHumspect.line.eqWidthfloatnullablee_EW6.2? Uncertainty of 6.2 micron PAH EQWumstat.errorfloatnullable