J/A+A/663/A59ivo://CDS.VizieR/J/A+A/663/A59doi:10.26093/cds/vizier.36630059CDSSaldana-Lopez A.Schaerer D.Chisholm J.Flury S.R.Jaskot A.E.,Worseck G.Makan K.Gazagnes S.Mauerhofer V.Verhamme A.Amorin R.O.,Ferguson H.C.Giavalisco M.Grazian A.Hayes M.J.Heckman T.M.,Henry A.Ji Z.Marques-Chaves R.McCandliss S.R.Oey M.S.Ostlin G.,Pentericci L.Thuan T.X.Trebitsch M.Vanzella E.Xu X.2023-02-22T09:00:14Z2023-02-22T09:20:38ZCDS support team

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

cds-question@unistra.frgalaxiesultraviolet-astronomyh-i-line-emissionline-intensitiesCombining 66 ultraviolet (UV) spectra and ancillary data from the recent Low-Redshift Lyman Continuum Survey (LzLCS) and 23 LyC observations by earlier studies, we form a statistical sample of star-forming galaxies at z~0.2-0.4 with which we study the role of cold interstellar medium (ISM) gas in the leakage of ionizing radiation. We also aim to establish empirical relations between the HI neutral and low-ionization state (LIS) absorption lines with different galaxy properties. We first constrain the massive star content (stellar ages and metallicities) and UV attenuation by fitting the stellar continuum with a combination of simple stellar population models. The models, together with accurate LyC flux measurements, allow us to determine the absolute LyC photon escape fraction for each galaxy (f_esc_^abs^f_esc_^abs^). We then measure the equivalent widths and residual fluxes of multiple HI and LIS lines, and the geometrical covering fraction of the UV emission, adopting the picket-fence model. The LyC escape fraction spans a wide range, with a median f_esc_^abs^f_esc_^abs^ (0.16, 0.84 quantiles) of 0.04 (0.02, 0.20), and 50 out of the 89 galaxies detected in the LyC (1{sigma} upper limits of f_esc_^abs^<=0.01 for non-detections, typically). The HI and LIS line equivalent widths scale with the UV luminosity and attenuation, and inversely with the residual flux of these lines. Additionally, Ly{alpha} equivalent widths scale with both the HI and LIS residual fluxes, but anti-correlate with the corresponding HI or LIS equivalent widths. The HI and LIS residual fluxes are correlated, indicating that the neutral gas is spatially traced by the low-ionization transitions. We find that the observed trends of the absorption lines and the UV attenuation are primarily driven by the geometric covering fraction of the gas. The observed nonuniform gas coverage also demonstrates that LyC photons escape through low-column-density channels in theISM. The equivalent widths and residual fluxes of both the HI and LIS lines strongly correlate with f_esc_^abs^ : strong LyC leakers (highest f_esc_^abs^) show weak absorption lines, low UV attenuation, and large Ly{alpha} equivalent widths. We provide several empirical calibrations to estimate f_esc_^abs^ from UV absorption lines. Finally, we show that simultaneous UV absorption line and dust attenuation measurements can, in general, predict the escape fraction of galaxies. We apply our method to available measurements of UV LIS lines of 15 star-forming galaxies at z~4-6 (plus 3 high-z galaxy composites), finding that these high-redshift, UV-bright galaxies (M_UV_<=-21) may have low escape fractions, f_esc_^abs^<=0.1. UV absorption lines trace the coldISM gas of galaxies, which governs the physics of the LyC escape. We show that, with some assumptions, the absolute LyC escape can be statistically predicted using UV absorption lines, and the method can be applied to study galaxies across a wide redshift range, including in the epoch of cosmic reionization.2022A&A...663A..59Shttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/663/A59CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/ApJS/260/1 : Low-redshift Lyman Continuum Survey (LzLCS). I. (Flury+, 2022)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/663/A59https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/663/A59http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/663/A59https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/663/A59https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/663/A59http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/663/A59GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/663/A59/tablea12 (UV-SED fits (table A1) and absorption lines (table A2) results for the LzLCS sample)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/663/A59/tablea12?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/663/A59/tablea12?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/663/A59/tablea12?GETtext/xml+votable180.050000true9.00264110.55200610.005555555555555556Cone search capability for table J/A+A/663/A59/tablea34 (UV-SED fits (table A3) and absorption lines (table A4) results for the literature sample)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/663/A59/tablea34?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/663/A59/tablea34?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/663/A59/tablea34?GETtext/xml+votable180.050000true141.384849714.05361060.0055555555555555566/4112 4124 4394 4442 4867 5428 5580 6077 7191 7387 8746 9099 9201 10859 10873 10963 10975 11504 11784 11832 17687 18011 18076 18118 18178 18215 21869 21886 21955 21987-21988 22308 25927 25981 26029 26084 26094 26206 26223 26230 26239 26305 26312-26313 26319 26323-26324 26327-26328 26351 26382 26412 26416 26434 27069 27071 27092 27094 27096 27107 27247 27258 27308 27323 27325 27352 27367 27372 27410 27435 27441-27442 27456 27660 27664 27668 27778 28453 28641 31163 31195 31419 31441 31463 31508 31630https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/663/A59?format=asciiUVRadiodefaultJ/A+A/663/A59/tablea12UV-SED fits (table A1) and absorption lines (table A2) results for the LzLCS samplerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordinte_RLIS? Weighted-average LIS residual flux errorstat.errorfloatnullablefabsescHI? Lyman series derived absolute photon escape fractionstat.fit.omcfloatnullableLyCtypeObject type (strong, weak or nonleaker)src.classcharzRedshiftsrc.redshiftfloatE(B-V)UV dust-attenuation parameter E(B-V)magphot.color.excessfloate_E(B-V)UV dust-attenuation parameter E(B-V) errormagstat.errorfloatAgeLight-weighted stellar ageMyrtime.agefloate_AgeLight-weighted stellar age errorMyrstat.error;time.agefloatZLight-weighted stellar metallicitySunphys.abund.Zfloate_ZLight-weighted stellar metallicity errorSunstat.error;src.redshiftfloatl_fabsesc[<= ] Limit flag on fabsescmeta.code.errorcharfabsescLyC absolute photon escape fractionstat.fit.omcfloatE_fabsesc? Error on fabsesc (upper value)stat.error;stat.maxfloatnullablee_fabsesc? Error on fabsesc (lower value)stat.errorfloatnullableMint1500Intrinic dust corrected absolute magnitude at 1500{AA} (AB)magphys.magAbsfloate_Mint1500Intrinic dust corrected absolute magnitude at 1500{AA} (AB) errormagstat.errorfloatMobs1500Observed UV absolute magnitude at 1500{AA} (AB)magphys.magAbsfloate_Mobs1500Observed UV absolute magnitude at 1500{AA} (AB) errormagstat.errorfloatWHIWeighted-average HI equivalent width0.1nmspect.line.eqWidthfloate_WHIWeighted-average HI equivalent width error0.1nmstat.errorfloatWLISWeighted-average LIS equivalent width0.1nmspect.line.eqWidthfloate_WLISWeighted-average LIS equivalent width error0.1nmstat.errorfloatRHI? Weighted-average HI residual flux (Cf(HI))stat.fit.residualfloatnullablee_RHI? Weighted-average HI residual flux errorstat.errorfloatnullableRLIS? Weighted-average LIS residual flux (Cf(LIS))stat.fit.residualfloatnullablee_fabsescHI? Lyman series derived absolute photon escape fraction errorstat.errorfloatnullablefabsescLIS? LIS derived absolute photon escape fractionstat.fit.omcfloatnullablee_fabsescLIS? LIS derived absolute photon escape fraction errorstat.errorfloatnullable_RAPositions from LzLCS (right ascension part)degpos.eq.ra;meta.main_DEPositions from LzLCS (declination part)degpos.eq.dec;meta.mainNameObject namemeta.id;meta.maincharJ/A+A/663/A59/tablea34UV-SED fits (table A3) and absorption lines (table A4) results for the literature sampleSimbadNameSimbad column added by the CDSmeta.idcharnullablezRedshiftsrc.redshiftfloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameObject namemeta.id;meta.maincharLyCtypeObject type (strong, weak or nonleaker)src.classcharE(B-V)UV dust-attenuation parameter E(B-V)magphot.color.excessfloate_E(B-V)UV dust-attenuation parameter E(B-V) errormagstat.errorfloatAgeLight-weighted stellar ageMyrtime.agefloate_AgeLight-weighted stellar age errorMyrstat.error;time.agefloatZLight-weighted stellar metallicitySunphys.abund.Zfloate_ZLight-weighted stellar metallicity errorSunstat.error;src.redshiftfloatl_fabsesc[<= ] Limit flag on fabsescmeta.code.errorcharfabsescLyC absolute photon escape fractionstat.fit.omcfloatE_fabsesc? Error on fabsesc (upper value)stat.error;stat.maxfloatnullablee_fabsesc? Error on fabsesc (lower value)stat.errorfloatnullableMint1500Intrinic dust corrected absolute magnitude at 1500{AA} (AB)magphys.magAbsfloate_Mint1500Intrinic dust corrected absolute magnitude at 1500{AA} (AB) errormagstat.errorfloatMobs1500Observed UV absolute magnitude at 1500{AA} (AB)magphys.magAbsfloate_Mobs1500Observed UV absolute magnitude at 1500{AA} (AB) errormagstat.errorfloatWHIWeighted-average HI equivalent width0.1nmspect.line.eqWidthfloate_WHIWeighted-average HI equivalent width error0.1nmstat.errorfloatWLISWeighted-average LIS equivalent width0.1nmspect.line.eqWidthfloate_WLISWeighted-average LIS equivalent width error0.1nmstat.errorfloatRHI? Weighted-average HI residual flux (Cf(HI))stat.fit.residualfloatnullablee_RHI? Weighted-average HI residual flux errorstat.errorfloatnullableRLIS? Weighted-average LIS residual flux (Cf(LIS))stat.fit.residualfloatnullablee_RLIS? Weighted-average LIS residual flux errorstat.errorfloatnullablefabsescHI? Lyman series derived absolute photon escape fractionstat.fit.omcfloatnullablee_fabsescHI? Lyman series derived absolute photon escape fraction errorstat.errorfloatnullablefabsescLIS? LIS derived absolute photon escape fractionstat.fit.omcfloatnullablee_fabsescLIS? LIS derived absolute photon escape fraction errorstat.errorfloatnullable_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.main