The COS-Halos Survey: Metallicities in the Low-redshift Circumgalactic Medium

dc.contributor.authorProchaska, J. Xavier
dc.contributor.authorWerk, Jessica K.
dc.contributor.authorWorseck, Gabor
dc.contributor.authorTripp, Todd M.
dc.contributor.authorTumlinson, Jason
dc.contributor.authorBurchett, Joseph N.
dc.contributor.authorFox, Andrew J.
dc.contributor.authorFumagalli, Michele
dc.contributor.authorLehner, Nicolas
dc.contributor.authorPeeples, Molly S.
dc.contributor.authorTejos, Nicolas
dc.date.accessioned2024-01-10T12:09:27Z
dc.date.available2024-01-10T12:09:27Z
dc.date.issued2017
dc.description.abstractWe analyze new far-ultraviolet spectra of 13 quasars from the z similar to 0.2 COS-Halos survey that cover the H I Lyman limit of 14 circumgalactic medium (CGM) systems. These data yield precise estimates or more constraining limits than previous COS-Halos measurements on the H I column densities N-H (I). We then apply a Monte-Carlo Markov chain approach on 32 systems from COS-Halos to estimate the metallicity of the cool (T similar to 10(4) K) CGM gas that gives rise to low-ionization state metal lines, under the assumption of photoionization equilibrium with the extragalactic UV background. The principle results are: (1) the CGM of field L* galaxies exhibits a declining H I surface density with impact parameter R-perpendicular to (at >99.5% confidence), (2) the transmission of ionizing radiation through CGM gas alone is 70 +/- 7%; (3) the metallicity distribution function of the cool CGM is unimodal with a median of 10(-0.51) Z(circle dot) and a 95% interval approximate to 1/50 Z(circle dot) to > 3 Z(circle dot); the incidence of metal=poor(< 1/100 Z) gas is low, implying any such gas discovered along quasar sightlines is typically unrelated to L* galaxies; (4) we find an unexpected increase in gas metallicity with declining N-H (I) (at >99.9% confidence) and, therefore, also with increasing R-perpendicular to; the high metallicity at large radii implies early enrichment; and (5) a non-parametric estimate of the cool CGM gas mass is M-CGM (cool) = (9.2 +/- 4.3) x 10(10) M-circle dot, cool 10, which together with new mass estimates for the hot CGM may resolve the galactic missing baryons problem. Future analyses of halo gas should focus on the underlying astrophysics governing the CGM, rather than processes that simply expel the medium from the halo.
dc.description.funderAssociation of Universities for Research in Astronomy, Inc., under NASA
dc.fechaingreso.objetodigital2024-05-30
dc.format.extent21 páginas
dc.fuente.origenWOS
dc.identifier.doi10.3847/1538-4357/aa6007
dc.identifier.eissn1538-4357
dc.identifier.issn0004-637X
dc.identifier.urihttps://doi.org/10.3847/1538-4357/aa6007
dc.identifier.urihttps://repositorio.uc.cl/handle/11534/76491
dc.identifier.wosidWOS:000398781300013
dc.information.autorucFísica;Tejos N;S/I;1040238
dc.issue.numero2
dc.language.isoen
dc.nota.accesoContenido parcial
dc.publisherIOP PUBLISHING LTD
dc.revistaASTROPHYSICAL JOURNAL
dc.rightsacceso restringido
dc.subjectgalaxies: halos
dc.subjectSTAR-FORMING GALAXIES
dc.subjectHIGH-VELOCITY CLOUDS
dc.subjectLYMAN LIMIT SYSTEMS
dc.subjectABSORPTION SYSTEMS
dc.subjectMILKY-WAY
dc.subjectHOT GAS
dc.subjectO VI
dc.subjectCHEMICAL ABUNDANCES
dc.subjectPHYSICAL-PROPERTIES
dc.subjectSTARBURST GALAXIES
dc.titleThe COS-Halos Survey: Metallicities in the Low-redshift Circumgalactic Medium
dc.typeartículo
dc.volumen837
sipa.codpersvinculados1040238
sipa.indexWOS
sipa.indexScopus
sipa.trazabilidadCarga SIPA;09-01-2024
Files
Original bundle
Now showing 1 - 1 of 1
Loading...
Thumbnail Image
Name:
The COS-Halos survey - Metallicities in the low-redshift circumgalactic medium.pdf
Size:
3.42 KB
Format:
Adobe Portable Document Format
Description: