Near-infrared imaging of low-redshift quasar host galaxies

K. K. McLeod, George H. Rieke

Research output: Contribution to journalArticle

79 Citations (Scopus)

Abstract

We present H-band images of a complete sample of 24 low-luminosity quasars selected from the Bright Quasar Survey. We detect the quasar host galaxy in at least 22 of these objects. We use a one-dimensional radial profile analysis to remove the contribution of the nucleus to the H-band light and to investigate the properties of the underlying galaxy. In most cases, the galaxy profiles are fitted better by exponential disk models than by de Vaucouleurs models. The average galaxy magnitude is 〈MH〈; = -23.9 mag, which is approximately the H magnitude of an L* galaxy. This result argues against the quasar activity being triggered by the merger of two large galaxies. No quasar host galaxies have inclinations greater than 60°, suggesting that obscuration near the active nucleus hides many of these objects from our view; their space density could be underestimated by a factor of ∼2. We combine our results with previously published results from CCD imaging to show that the galaxies we detect are about 0.5 mag bluer in V - H than normal galaxies. Such colors can arise from a heightened level of star formation compared with normal galaxies and are consistent with these galaxies having been the sites of luminous starbursts about 108 yr ago.

Original languageEnglish (US)
Pages (from-to)58-67
Number of pages10
JournalAstrophysical Journal
Volume420
Issue number1
StatePublished - Jan 1 1994

Fingerprint

quasars
near infrared
galaxies
merger
nuclei
space density
occultation
profiles
inclination
star formation
charge coupled devices
luminosity
analysis
color

Keywords

  • Galaxies: photometry
  • Infrared: galaxies
  • Quasars: general

ASJC Scopus subject areas

  • Space and Planetary Science

Cite this

Near-infrared imaging of low-redshift quasar host galaxies. / McLeod, K. K.; Rieke, George H.

In: Astrophysical Journal, Vol. 420, No. 1, 01.01.1994, p. 58-67.

Research output: Contribution to journalArticle

@article{a86be2a244614203a35b29bac877971e,
title = "Near-infrared imaging of low-redshift quasar host galaxies",
abstract = "We present H-band images of a complete sample of 24 low-luminosity quasars selected from the Bright Quasar Survey. We detect the quasar host galaxy in at least 22 of these objects. We use a one-dimensional radial profile analysis to remove the contribution of the nucleus to the H-band light and to investigate the properties of the underlying galaxy. In most cases, the galaxy profiles are fitted better by exponential disk models than by de Vaucouleurs models. The average galaxy magnitude is 〈MH〈; = -23.9 mag, which is approximately the H magnitude of an L* galaxy. This result argues against the quasar activity being triggered by the merger of two large galaxies. No quasar host galaxies have inclinations greater than 60°, suggesting that obscuration near the active nucleus hides many of these objects from our view; their space density could be underestimated by a factor of ∼2. We combine our results with previously published results from CCD imaging to show that the galaxies we detect are about 0.5 mag bluer in V - H than normal galaxies. Such colors can arise from a heightened level of star formation compared with normal galaxies and are consistent with these galaxies having been the sites of luminous starbursts about 108 yr ago.",
keywords = "Galaxies: photometry, Infrared: galaxies, Quasars: general",
author = "McLeod, {K. K.} and Rieke, {George H.}",
year = "1994",
month = "1",
day = "1",
language = "English (US)",
volume = "420",
pages = "58--67",
journal = "Astrophysical Journal",
issn = "0004-637X",
publisher = "IOP Publishing Ltd.",
number = "1",

}

TY - JOUR

T1 - Near-infrared imaging of low-redshift quasar host galaxies

AU - McLeod, K. K.

AU - Rieke, George H.

PY - 1994/1/1

Y1 - 1994/1/1

N2 - We present H-band images of a complete sample of 24 low-luminosity quasars selected from the Bright Quasar Survey. We detect the quasar host galaxy in at least 22 of these objects. We use a one-dimensional radial profile analysis to remove the contribution of the nucleus to the H-band light and to investigate the properties of the underlying galaxy. In most cases, the galaxy profiles are fitted better by exponential disk models than by de Vaucouleurs models. The average galaxy magnitude is 〈MH〈; = -23.9 mag, which is approximately the H magnitude of an L* galaxy. This result argues against the quasar activity being triggered by the merger of two large galaxies. No quasar host galaxies have inclinations greater than 60°, suggesting that obscuration near the active nucleus hides many of these objects from our view; their space density could be underestimated by a factor of ∼2. We combine our results with previously published results from CCD imaging to show that the galaxies we detect are about 0.5 mag bluer in V - H than normal galaxies. Such colors can arise from a heightened level of star formation compared with normal galaxies and are consistent with these galaxies having been the sites of luminous starbursts about 108 yr ago.

AB - We present H-band images of a complete sample of 24 low-luminosity quasars selected from the Bright Quasar Survey. We detect the quasar host galaxy in at least 22 of these objects. We use a one-dimensional radial profile analysis to remove the contribution of the nucleus to the H-band light and to investigate the properties of the underlying galaxy. In most cases, the galaxy profiles are fitted better by exponential disk models than by de Vaucouleurs models. The average galaxy magnitude is 〈MH〈; = -23.9 mag, which is approximately the H magnitude of an L* galaxy. This result argues against the quasar activity being triggered by the merger of two large galaxies. No quasar host galaxies have inclinations greater than 60°, suggesting that obscuration near the active nucleus hides many of these objects from our view; their space density could be underestimated by a factor of ∼2. We combine our results with previously published results from CCD imaging to show that the galaxies we detect are about 0.5 mag bluer in V - H than normal galaxies. Such colors can arise from a heightened level of star formation compared with normal galaxies and are consistent with these galaxies having been the sites of luminous starbursts about 108 yr ago.

KW - Galaxies: photometry

KW - Infrared: galaxies

KW - Quasars: general

UR - http://www.scopus.com/inward/record.url?scp=12044259206&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=12044259206&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:12044259206

VL - 420

SP - 58

EP - 67

JO - Astrophysical Journal

JF - Astrophysical Journal

SN - 0004-637X

IS - 1

ER -