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Related papers: Calibrating Emission Lines as Quasar Bolometers

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Broad emission-line outflows of active galactic nuclei (AGNs) have been proposed for many years but are very difficult to quantitatively study because of the coexistence of the gravitationally-bound and outflow emission. We present detailed…

Astrophysics of Galaxies · Physics 2017-02-22 Shaohua Zhang , Hongyan Zhou , Xiheng Shi , Xiang Pan , Ji Wang , Ning Jiang , Tuo Ji , Peng Jiang , Wenjuan Liu , Huiyuan Wang

We present the results of the analysis of a sample of 17 low-luminosity (L_x < 1e42 erg/s), radio loud AGNs in massive galaxies. The sample is extracted from the SDSS database and it spans uniformly a wide range in optical [OIII] emission…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 F. de Gasperin , A. Merloni , P. Sell , P. Best , S. Heinz , G. Kauffmann

The Balmer emission originated in the broad line region (BLR) of active galactic nuclei (AGNs) could be either weak and difficult to detect, or even absent, for low luminosity AGNs, as LINERs. Our goals in this paper are threefold. First,…

The masses and emission-line region sizes of Active Galactic Nuclei (AGNs) can be measured by ``reverberation-mapping'' (measuring the lag of the emission-line luminosity after changes in the continuum). We use tis technique to calibrate…

Astrophysics · Physics 2008-11-26 A. Wandel , B. M. Peterson , M. A. Malkan

We have obtained quasi-simultaneous ultraviolet-optical spectra for 22 out of 23 quasars in the complete PG-X-ray sample with redshift, z<0.4, and M_B<-23. The spectra cover rest-frame wavelengths from at least Lyman-alpha to H-alpha. Here…

Astrophysics · Physics 2008-11-26 Zhaohui Shang , Beverley J. Wills , D. Wills , Michael S. Brotherton

Aims: Our aim is to identify the dominant molecular cooling lines and characteristic emission features in the 1.3 mm window of distinct regions in the northern part of the Orion A molecular cloud. By defining and analysing template regions,…

Astrophysics of Galaxies · Physics 2020-04-15 N. Brinkmann , F. Wyrowski , J. Kauffmann , D. Colombo , K. M. Menten , X. D. Tang , R. Güsten

We have compiled a sample of 165 radio galaxies from the literature to study the properties of the extended emission line regions and their interaction with the radio source over a large range of redshift 0<z<5.2. For each source, we have…

Astrophysics · Physics 2007-05-23 Carlos De Breuck , Huub Rottgering , George Miley , Wil van Breugel , Philip Best

We examine the variability of the high-ionization Lyman alpha lambda 1216 broad emission line (BEL) in a sample of 61 high-luminosity, high-redshift quasars observed at two epochs by the Sloan Digital Sky Survey. These bright objects lie in…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-26 Sui Chi Woo , David A. Turnshek , Carles Badenes , Steven Bickerton

Comparison of six high-redshift quasar spectra obtained with the Large Binocular Telescope with previous observations from the Sloan Digital Sky Survey shows that failure to correctly identify absorption and other problems with accurate…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Kelly D. Denney , Richard W. Pogge , Roberto J. Assef , Christopher S. Kochanek , Bradley M. Peterson , Marianne Vestergaard

The combination of the linear size from reverberation mapping (RM) and the angular distance of the broad line region (BLR) from spectroastrometry (SA) in active galactic nuclei (AGNs) can be used to measure the Hubble constant $H_0$.…

Astrophysics of Galaxies · Physics 2021-06-28 Xiaer Zhang , Zhicheng He , Tinggui Wang , Hengxiao Guo

In this paper, a new method is proposed to estimate the broad-line region sizes of UV lines $R^{\rm{uv}}_{\rm{BLR}}$. It is applied to 3C 273. First, we derive the time lags of radio emission relative to broad emission lines Ly$\alpha$ and…

Cosmology and Nongalactic Astrophysics · Physics 2013-11-07 H. T. Liu , J. M. Bai , J. M. Wang , S. K. Li

The radiative efficiency of AGN is commonly estimated based on the total mass accreted and the total AGN light emitted per unit volume in the universe integrated over time (the Soltan argument). In individual AGN, thin accretion disk model…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Shane W. Davis , Ari Laor

New reverberation mapping measurements of the size of the optical iron emission-line region in quasars are provided, and a tentative size-luminosity relation for this component is reported. Combined with lag measurements in low-luminosity…

Astrophysics of Galaxies · Physics 2014-04-25 Doron Chelouche , Stephen E. Rafter , Gabriel I. Cotlier , Shai Kaspi , Aaron J. Barth

The great power offered by photoionization models of Active Galactic Nuclei (AGN) emission-line regions has long been mitigated by the fact that very little is known about the spectral energy distribution (SED) between the Lyman limit,…

High Energy Astrophysical Phenomena · Physics 2020-05-13 Gary Ferland , Chris Done , Chichuan Jin , Hermine Landt , Martin Ward

Using the SCUBA bolometer array on the JCMT, we have carried out a submillimetre survey of Broad Absorption Line quasars (BALQs). The sample has been chosen to match, in redshift and optical luminosity, an existing benchmark 850um sample of…

Astrophysics · Physics 2008-11-26 R. S. Priddey , S. C. Gallagher , K. G. Isaak , R. G. Sharp , R. G. McMahon , H. M. Butner

We explore the variability of quasars in the MgII and Hbeta broad emission lines and UV/optical continuum emission using the Sloan Digital Sky Survey Reverberation Mapping project (SDSS-RM). This is the largest spectroscopic study of quasar…

We study the relation between the mass accretion rate, the jet power, and the black hole mass of blazars. To this aim, we make use of the Sloan Digital Sky Survey (SDSS) and the 11 months catalog of blazars detected at energies larger than…

High Energy Astrophysical Phenomena · Physics 2012-05-18 T. Sbarrato , G. Ghisellini , L. Maraschi , M. Colpi

In this work we investigate the properties of the broad emission line components in the Balmer series of a sample of Type 1 Active Galactic Nuclei (AGN). Using the Boltzmann Plot method as a diagnostic tool for physical conditions in the…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 G. La Mura , F. Di Mille , L. Č. Popović , S. Ciroi , P. Rafanelli , D. Ilić

The inter-line comparison between high- and low-ionization emission lines has yielded a wealth of information on the quasar broad line region (BLR) structure and dynamics, including perhaps the earliest unambiguous evidence in favor of a…

Efficient selection of emission line galaxies at z > 1 by photometric information in wide field surveys is one of the keys for future spectroscopic surveys to constrain dark energy using the baryon acoustic oscillation (BAO) signature. Here…