Infrared spectra and photometry of complete samples of palomar-green and two micron all sky survey quasars

Yong Shi, George H. Rieke, P. M. Ogle, K. Y L Su, Z. Balog

Research output: Contribution to journalArticle

10 Citations (Scopus)

Abstract

As a step toward a comprehensive overview of the infrared (IR) diagnostics of the central engines and host galaxies of quasars at low redshift, we present Spitzer Space Telescope spectroscopic (5-40 μm) and photometric (24, 70, and 160 μm) measurements of all Palomar-Green (PG) quasars at z < 0.5 and Two Micron All Sky Survey (2MASS) quasars at z < 0.3. We supplement these data with Herschel measurements at 160 μm. The sample is composed of 87 optically selected PG quasars and 52 near-IR-selected 2MASS quasars. Here we present the data, measure the prominent spectral features, and separate emission due to star formation from that emitted by the dusty circumnuclear torus. We find that the mid-IR (5-30 μm) spectral shape for the torus is largely independent of quasar IR luminosity with scatter in the spectral energy distribution (SED) shape of ≲0.2 dex. Except for the silicate features, no large difference is observed between PG (unobscured - silicate emission) and 2MASS (obscured - silicate absorption) quasars. Only mild silicate features are observed in both cases. When in emission, the peak wavelength of the silicate feature tends to be longer than 9.7 μm, possibly indicating effects on grain properties near the active galactic nucleus. The IR color is shown to correlate with the equivalent width of the aromatic features, indicating that the slope of the quasar mid- to far-IR SED is to first order driven by the fraction of radiation from star formation in the IR bands.

Original languageEnglish (US)
Article number214
JournalAstrophysical Journal, Supplement Series
Volume214
Issue number2
DOIs
StatePublished - 2014

Fingerprint

infrared photometry
quasars
infrared spectra
silicate
silicates
spectral energy distribution
star formation
energy
engine
near infrared
Space Infrared Telescope Facility
supplements
wavelength
active galactic nuclei
engines
luminosity
slopes
galaxies
color
radiation

Keywords

  • galaxies: active
  • galaxies: starburst
  • infrared: galaxies

ASJC Scopus subject areas

  • Space and Planetary Science
  • Astronomy and Astrophysics

Cite this

Infrared spectra and photometry of complete samples of palomar-green and two micron all sky survey quasars. / Shi, Yong; Rieke, George H.; Ogle, P. M.; Su, K. Y L; Balog, Z.

In: Astrophysical Journal, Supplement Series, Vol. 214, No. 2, 214, 2014.

Research output: Contribution to journalArticle

@article{b59df98581764720ae2586a0054a8b0b,
title = "Infrared spectra and photometry of complete samples of palomar-green and two micron all sky survey quasars",
abstract = "As a step toward a comprehensive overview of the infrared (IR) diagnostics of the central engines and host galaxies of quasars at low redshift, we present Spitzer Space Telescope spectroscopic (5-40 μm) and photometric (24, 70, and 160 μm) measurements of all Palomar-Green (PG) quasars at z < 0.5 and Two Micron All Sky Survey (2MASS) quasars at z < 0.3. We supplement these data with Herschel measurements at 160 μm. The sample is composed of 87 optically selected PG quasars and 52 near-IR-selected 2MASS quasars. Here we present the data, measure the prominent spectral features, and separate emission due to star formation from that emitted by the dusty circumnuclear torus. We find that the mid-IR (5-30 μm) spectral shape for the torus is largely independent of quasar IR luminosity with scatter in the spectral energy distribution (SED) shape of ≲0.2 dex. Except for the silicate features, no large difference is observed between PG (unobscured - silicate emission) and 2MASS (obscured - silicate absorption) quasars. Only mild silicate features are observed in both cases. When in emission, the peak wavelength of the silicate feature tends to be longer than 9.7 μm, possibly indicating effects on grain properties near the active galactic nucleus. The IR color is shown to correlate with the equivalent width of the aromatic features, indicating that the slope of the quasar mid- to far-IR SED is to first order driven by the fraction of radiation from star formation in the IR bands.",
keywords = "galaxies: active, galaxies: starburst, infrared: galaxies",
author = "Yong Shi and Rieke, {George H.} and Ogle, {P. M.} and Su, {K. Y L} and Z. Balog",
year = "2014",
doi = "10.1088/0067-0049/214/2/23",
language = "English (US)",
volume = "214",
journal = "Astrophysical Journal, Supplement Series",
issn = "0067-0049",
publisher = "IOP Publishing Ltd.",
number = "2",

}

TY - JOUR

T1 - Infrared spectra and photometry of complete samples of palomar-green and two micron all sky survey quasars

AU - Shi, Yong

AU - Rieke, George H.

AU - Ogle, P. M.

AU - Su, K. Y L

AU - Balog, Z.

PY - 2014

Y1 - 2014

N2 - As a step toward a comprehensive overview of the infrared (IR) diagnostics of the central engines and host galaxies of quasars at low redshift, we present Spitzer Space Telescope spectroscopic (5-40 μm) and photometric (24, 70, and 160 μm) measurements of all Palomar-Green (PG) quasars at z < 0.5 and Two Micron All Sky Survey (2MASS) quasars at z < 0.3. We supplement these data with Herschel measurements at 160 μm. The sample is composed of 87 optically selected PG quasars and 52 near-IR-selected 2MASS quasars. Here we present the data, measure the prominent spectral features, and separate emission due to star formation from that emitted by the dusty circumnuclear torus. We find that the mid-IR (5-30 μm) spectral shape for the torus is largely independent of quasar IR luminosity with scatter in the spectral energy distribution (SED) shape of ≲0.2 dex. Except for the silicate features, no large difference is observed between PG (unobscured - silicate emission) and 2MASS (obscured - silicate absorption) quasars. Only mild silicate features are observed in both cases. When in emission, the peak wavelength of the silicate feature tends to be longer than 9.7 μm, possibly indicating effects on grain properties near the active galactic nucleus. The IR color is shown to correlate with the equivalent width of the aromatic features, indicating that the slope of the quasar mid- to far-IR SED is to first order driven by the fraction of radiation from star formation in the IR bands.

AB - As a step toward a comprehensive overview of the infrared (IR) diagnostics of the central engines and host galaxies of quasars at low redshift, we present Spitzer Space Telescope spectroscopic (5-40 μm) and photometric (24, 70, and 160 μm) measurements of all Palomar-Green (PG) quasars at z < 0.5 and Two Micron All Sky Survey (2MASS) quasars at z < 0.3. We supplement these data with Herschel measurements at 160 μm. The sample is composed of 87 optically selected PG quasars and 52 near-IR-selected 2MASS quasars. Here we present the data, measure the prominent spectral features, and separate emission due to star formation from that emitted by the dusty circumnuclear torus. We find that the mid-IR (5-30 μm) spectral shape for the torus is largely independent of quasar IR luminosity with scatter in the spectral energy distribution (SED) shape of ≲0.2 dex. Except for the silicate features, no large difference is observed between PG (unobscured - silicate emission) and 2MASS (obscured - silicate absorption) quasars. Only mild silicate features are observed in both cases. When in emission, the peak wavelength of the silicate feature tends to be longer than 9.7 μm, possibly indicating effects on grain properties near the active galactic nucleus. The IR color is shown to correlate with the equivalent width of the aromatic features, indicating that the slope of the quasar mid- to far-IR SED is to first order driven by the fraction of radiation from star formation in the IR bands.

KW - galaxies: active

KW - galaxies: starburst

KW - infrared: galaxies

UR - http://www.scopus.com/inward/record.url?scp=84907481619&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84907481619&partnerID=8YFLogxK

U2 - 10.1088/0067-0049/214/2/23

DO - 10.1088/0067-0049/214/2/23

M3 - Article

AN - SCOPUS:84907481619

VL - 214

JO - Astrophysical Journal, Supplement Series

JF - Astrophysical Journal, Supplement Series

SN - 0067-0049

IS - 2

M1 - 214

ER -