Evidence for Late-time Feedback from the Discovery of Multiphase Gas in a Massive Elliptical at z = 0.4
AuthorZahedy, Fakhri S.
Decker French, K.
Zabludoff, Ann I.
AffiliationUniv Arizona, Dept Astron
Univ Arizona, Steward Observ
KeywordsQuasar absorption line spectroscopy
MetadataShow full item record
PublisherIOP PUBLISHING LTD
CitationZahedy, F. S., Chen, H. W., Boettcher, E., Rauch, M., French, K. D., & Zabludoff, A. I. (2020). Evidence for Late-time Feedback from the Discovery of Multiphase Gas in a Massive Elliptical at z = 0.4. The Astrophysical Journal Letters, 904(1), L10.
JournalASTROPHYSICAL JOURNAL LETTERS
Rights© 2020. The American Astronomical Society. All rights reserved.
Collection InformationThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at email@example.com.
AbstractWe report the first detection of multiphase gas within a quiescent galaxy beyond z approximate to 0. The observations use the brighter image of doubly lensed QSO HE 0047-1756 to probe the interstellar medium (ISM) of the massive (M-star approximate to 10(11) M-circle dot) elliptical lens galaxy at z(gal) = 0.408. Using Hubble Space Telescope's Cosmic Origins Spectrograph (COS), we obtain a medium-resolution FUV spectrum of the lensed QSO and identify numerous absorption features from H-2 in the lens ISM at projected distance d = 4.6 kpc. The H-2 column density is log N(H-2)/cm(-2) 17.8(-0.3)(+0.1) with a molecular gas fraction of f(H2) = 2%-5% , roughly consistent with some local quiescent galaxies. The new COS spectrum also reveals kinematically complex absorption features from highly ionized species O VI and N V with column densities log N(O VI) cm(-2) = 15.2 +/- 0.1 and log N(N V) cm(-2) = 14.6 +/- 0.1, among the highest known in external galaxies. Assuming the high-ionization absorption features originate in a transient warm (T similar to 105 K) phase undergoing radiative cooling from a hot halo surrounding the galaxy, we infer a mass accretion rate of similar to 0.5-1.5 M-circle dot yr(-1). The lack of star formation in the lens suggests that the bulk of this flow is returned to the hot halo, implying a heating rate of similar to 1048 erg yr(-1). Continuous heating from evolved stellar populations (primarily SNe Ia but also winds from AGB stars) may suffice to prevent a large accumulation of cold gas in the ISM, even in the absence of strong feedback from an active nucleus.
VersionFinal published version
SponsorsSpace Telescope Science Institute