A glimpse at quasar host galaxy Far-UV emission using damped Lyα's as natural coronagraphs (2024)

Cai, Z., Fan, X., Noterdaeme, P., Wang, R., McGreer, I., Carithers, B., Bian, F., Miralda-Escudé, J., Finley, H., Pâris, I., Schneider, D. P., Zakamska, N. L., Ge, J., Petitjean, P., & Slosar, A. (2014). A glimpse at quasar host galaxy Far-UV emission using damped Lyα's as natural coronagraphs. Astrophysical Journal, 793(2), Article 139. https://doi.org/10.1088/0004-637X/793/2/139

Cai, Zheng ; Fan, Xiaohui ; Noterdaeme, Pasquier et al. / A glimpse at quasar host galaxy Far-UV emission using damped Lyα's as natural coronagraphs. In: Astrophysical Journal. 2014 ; Vol. 793, No. 2.

@article{c15052b5517044d89666fcd932594e08,

title = "A glimpse at quasar host galaxy Far-UV emission using damped Lyα's as natural coronagraphs",

abstract = "In merger-driven models of massive galaxy evolution, the luminous quasar phase is expected to be accompanied by vigorous star formation in quasar host galaxies. In this paper, we use high column density damped Lyα (DLA) systems along quasar sight lines as natural coronagraphs to directly study the far-UV (FUV) radiation from the host galaxies of luminous background quasars. We have stacked the spectra of ∼2000 DLA systems (N H I> 1020.6cm-2) with a median absorption redshift 〈z〉 = 2.6 selected from quasars observed in the SDSS-III Baryon Oscillation Spectroscopic Survey. We detect residual flux in the dark troughs of the composite DLA spectra. The level of this residual flux significantly exceeds systematic errors in the Sloan Digital Sky Survey fiber sky subtraction; furthermore, the residual flux is strongly correlated with the continuum luminosity of the background quasar, while uncorrelated with DLA column density or metallicity. We conclude that the flux could be associated with the average FUV radiation from the background quasar host galaxies (with medium redshift 〈z〉 = 3.1) that is not blocked by the intervening DLA. Assuming that all of the detected flux originates from quasar hosts, for the highest quasar luminosity bin (〈L〉 = 2.5 × 1013L O), the host galaxy has an FUV intensity of 1.5 ± 0.2 × 1040erg s-1{\AA}-1; this corresponds to an unobscured UV star formation rate of 9 M Oyr-1.",

keywords = "cosmology: observations, galaxies: high-redshift, quasars: absorption lines, quasars: general",

author = "Zheng Cai and Xiaohui Fan and Pasquier Noterdaeme and Ran Wang and Ian McGreer and Bill Carithers and Fuyan Bian and Jordi Miralda-Escud{\'e} and Hayley Finley and Isabelle P{\^a}ris and Schneider, {Donald P.} and Zakamska, {Nadia L.} and Jian Ge and Patrick Petitjean and Anze Slosar",

note = "Publisher Copyright: {\textcopyright} 2014. The American Astronomical Society. All rights reserved..",

year = "2014",

month = oct,

day = "1",

doi = "10.1088/0004-637X/793/2/139",

language = "English",

volume = "793",

journal = "Astrophysical Journal",

issn = "0004-637X",

publisher = "American Astronomical Society",

number = "2",

}

Cai, Z, Fan, X, Noterdaeme, P, Wang, R, McGreer, I, Carithers, B, Bian, F, Miralda-Escudé, J, Finley, H, Pâris, I, Schneider, DP, Zakamska, NL, Ge, J, Petitjean, P & Slosar, A 2014, 'A glimpse at quasar host galaxy Far-UV emission using damped Lyα's as natural coronagraphs', Astrophysical Journal, vol. 793, no. 2, 139. https://doi.org/10.1088/0004-637X/793/2/139

A glimpse at quasar host galaxy Far-UV emission using damped Lyα's as natural coronagraphs. / Cai, Zheng; Fan, Xiaohui; Noterdaeme, Pasquier et al.
In: Astrophysical Journal, Vol. 793, No. 2, 139, 01.10.2014.

Research output: Contribution to journal › Article › peer-review

TY - JOUR

T1 - A glimpse at quasar host galaxy Far-UV emission using damped Lyα's as natural coronagraphs

AU - Cai, Zheng

AU - Fan, Xiaohui

AU - Noterdaeme, Pasquier

AU - Wang, Ran

AU - McGreer, Ian

AU - Carithers, Bill

AU - Bian, Fuyan

AU - Miralda-Escudé, Jordi

AU - Finley, Hayley

AU - Pâris, Isabelle

AU - Schneider, Donald P.

AU - Zakamska, Nadia L.

AU - Ge, Jian

AU - Petitjean, Patrick

AU - Slosar, Anze

N1 - Publisher Copyright:© 2014. The American Astronomical Society. All rights reserved..

PY - 2014/10/1

Y1 - 2014/10/1

N2 - In merger-driven models of massive galaxy evolution, the luminous quasar phase is expected to be accompanied by vigorous star formation in quasar host galaxies. In this paper, we use high column density damped Lyα (DLA) systems along quasar sight lines as natural coronagraphs to directly study the far-UV (FUV) radiation from the host galaxies of luminous background quasars. We have stacked the spectra of ∼2000 DLA systems (N H I> 1020.6cm-2) with a median absorption redshift 〈z〉 = 2.6 selected from quasars observed in the SDSS-III Baryon Oscillation Spectroscopic Survey. We detect residual flux in the dark troughs of the composite DLA spectra. The level of this residual flux significantly exceeds systematic errors in the Sloan Digital Sky Survey fiber sky subtraction; furthermore, the residual flux is strongly correlated with the continuum luminosity of the background quasar, while uncorrelated with DLA column density or metallicity. We conclude that the flux could be associated with the average FUV radiation from the background quasar host galaxies (with medium redshift 〈z〉 = 3.1) that is not blocked by the intervening DLA. Assuming that all of the detected flux originates from quasar hosts, for the highest quasar luminosity bin (〈L〉 = 2.5 × 1013L O), the host galaxy has an FUV intensity of 1.5 ± 0.2 × 1040erg s-1Å-1; this corresponds to an unobscured UV star formation rate of 9 M Oyr-1.

AB - In merger-driven models of massive galaxy evolution, the luminous quasar phase is expected to be accompanied by vigorous star formation in quasar host galaxies. In this paper, we use high column density damped Lyα (DLA) systems along quasar sight lines as natural coronagraphs to directly study the far-UV (FUV) radiation from the host galaxies of luminous background quasars. We have stacked the spectra of ∼2000 DLA systems (N H I> 1020.6cm-2) with a median absorption redshift 〈z〉 = 2.6 selected from quasars observed in the SDSS-III Baryon Oscillation Spectroscopic Survey. We detect residual flux in the dark troughs of the composite DLA spectra. The level of this residual flux significantly exceeds systematic errors in the Sloan Digital Sky Survey fiber sky subtraction; furthermore, the residual flux is strongly correlated with the continuum luminosity of the background quasar, while uncorrelated with DLA column density or metallicity. We conclude that the flux could be associated with the average FUV radiation from the background quasar host galaxies (with medium redshift 〈z〉 = 3.1) that is not blocked by the intervening DLA. Assuming that all of the detected flux originates from quasar hosts, for the highest quasar luminosity bin (〈L〉 = 2.5 × 1013L O), the host galaxy has an FUV intensity of 1.5 ± 0.2 × 1040erg s-1Å-1; this corresponds to an unobscured UV star formation rate of 9 M Oyr-1.

KW - cosmology: observations

KW - galaxies: high-redshift

KW - quasars: absorption lines

KW - quasars: general

UR - http://www.scopus.com/inward/record.url?scp=84907214106&partnerID=8YFLogxK

U2 - 10.1088/0004-637X/793/2/139

DO - 10.1088/0004-637X/793/2/139

M3 - Article

SN - 0004-637X

VL - 793

JO - Astrophysical Journal

JF - Astrophysical Journal

IS - 2

M1 - 139

ER -

Cai Z, Fan X, Noterdaeme P, Wang R, McGreer I, Carithers B et al. A glimpse at quasar host galaxy Far-UV emission using damped Lyα's as natural coronagraphs. Astrophysical Journal. 2014 Oct 1;793(2):139. doi: 10.1088/0004-637X/793/2/139