Zobrazeno 1 - 10
of 32
pro vyhledávání: '"Michael Eracleous"'
We introduce a Bayesian approach coupled with a Markov Chain Monte Carlo (MCMC) method and the maximum likelihood statistic for fitting the profiles of narrow absorption lines (NALs) in quasar spectra. This method also incorporates overlap between di
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::1ec01101e495e0da555c66bf14425b49
Autor:
Michael Eracleous, Robin Ciardullo, Renbin Yan, Mallory Molina, Caryl Gronwall, Nikhil Ajgaonkar, Donald P. Schneider, Médéric Boquien
The attenuation of light in star forming galaxies is correlated with a multitude of physical parameters including star formation rate, metallicity and total dust content. This variation in attenuation is even more prevalent on the kiloparsec scale, w
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::ba594d17f59afd8c2bd5959a3fc1cc0a
http://arxiv.org/abs/1905.02166
http://arxiv.org/abs/1905.02166
Publikováno v:
New Astronomy Reviews. 53:133-139
Broad, double-peaked, Balmer emission lines are found in the optical spectra of a relatively small fraction of active galactic nuclei. They can be an extremely useful diagnostic for the structure and dynamics of the “broad-line region” (the mediu
Publikováno v:
The Astrophysical Journal. 687:869-883
We study the 0.5-10keV emission of a sample of five of the broadest double-peaked Balmer-line emitters with Chandra. The Balmer lines of these objects originate close (within a few hundred gravitational radii) to the central black holes of the Active
Autor:
Claudia Winge, Thaisa Storchi-Bergmann, Jack A. Baldwin, Bradley M. Peterson, Rodrigo Nemmen, J. S. Schimoia, Michael Eracleous, Dirk Grupe
Publikováno v:
Repositório Institucional da USP (Biblioteca Digital da Produção Intelectual)
Universidade de São Paulo (USP)
instacron:USP
Universidade de São Paulo (USP)
instacron:USP
Recent studies have suggested that the short-timescale ($\lesssim7$ days) variability of the broad ($\sim$10,000 km s$^{-1}$) double-peaked H$\alpha$ profile of the LINER nucleus of NGC1097 could be driven by a variable X-ray emission from a central
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::9aa1b868cf9e2f6d802d55d3e1680cc6
http://arxiv.org/abs/1411.4682
http://arxiv.org/abs/1411.4682
Autor:
Gordon P. Garmire, Michael Eracleous, Nicholas D. Morgan, Mark W. Bautz, George Chartas, Eric Agol
Publikováno v:
The Astrophysical Journal. 568:509-521
We present results from monitoring of the distant (z = 2.64), gravitationally lensed quasar MG J0414+0534 with the Chandra X-ray Observatory. An Fe Ka line at 6.49 +/- 0.09 keV (rest-frame) with an equivalent width of ~ 190eV consistent with fluoresc
Autor:
Daniel H. McIntosh, Alexei V. Filippenko, Luis C. Ho, Joseph C. Shields, Greg Rudnick, Hans-Walter Rix, Wallace L. W. Sargent, Michael Eracleous
Publikováno v:
The Astrophysical Journal. 541:120-125
Spectra taken with HST reveal that NGC 4450 emits Balmer emission lines with displaced double peaks and extremely high-velocity wings. This characteristic line profile, previously seen in a few nearby LINERs and in a small fraction of broad-line radi
Publikováno v:
The Astrophysical Journal. 501:103-109
New optical spectra of the original narrow-line quasar 1E 0449.4-1823 show that it now has broad emission lines of considerable strength, eliminating it as a "type 2 QSO" candidate. We suggest that the behavior of 1E 0449.4-1823 is the same as that o
Autor:
Michael Eracleous
Publikováno v:
Advances in Space Research. 21:33-45
The most direct, dynamical evidence for the presence of accretion disks in the central engines of active galaxies comes from observations of very broad, double-peaked emission lines. These “exotic” line profiles are found preferentially in radio-
Publikováno v:
The Astrophysical Journal. 485:570-580
The optical spectrum of the broad-line radio galaxy Arp 102B has been monitored for more than thirteen years to investigate the nature of the source of its broad, double-peaked hydrogen Balmer emission lines. The shape of the lines varied subtly; the