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The hunt for red quasars: luminous obscured black hole growth unveiled in the stripe 82 X-Ray survey
(IOP Publishing Ltd, 2017)
We present results of a ground-based near-infrared campaign with Palomar TripleSpec, Keck NIRSPEC, and Gemini GNIRS to target two samples of reddened active galactic nucleus (AGN) candidates from the 31 deg(2) Stripe 82 ...
WEAK LINE QUASARS AT HIGH REDSHIFT: EXTREMELY HIGH ACCRETION RATES OR ANEMIC BROAD-LINE REGIONS?
(The American Astronomical Society, 2010-09-28)
We present Gemini-North K-band spectra of two representative members of the class of high-redshift quasars with
exceptionally weak rest-frame ultraviolet emission lines (WLQs), SDSS J114153.34+021924.3 at z = 3.55 and
SDSS ...
Reverberation Mapping of Luminous Quasars at High z
(Institute of Physics Publishing, 2018)
We present reverberation mapping (RM) results for 17 high-redshift, high-luminosity quasars with good-quality R-band and emission-line light curves. We are able to measure statistically significant lags for Lyα (11 objects), ...
Ultraviolet Fe ii emission in fainter quasars: luminosity dependences, and the influence of environments
(Oxford Univ. Press, 2016)
We investigate the strength of ultraviolet Fe ii emission in fainter quasars compared with brighter quasars for 1.0 a parts per thousand currency sign z a parts per thousand currency sign 1.8, using the Sloan Digital Sky ...
Vínculos observacionais na interação no setor escuro utilizando dados de quasares
(Universidade Federal do Rio Grande do NorteBrasilUFRNFísica, 2018-11-29)
A nonlinear relationship between the luminosity in the ultraviolet and X-ray bands in quasars was used with the Markov Chain Monte Carlo computational method to impose constraints to parameters of this relationship. For ...
Cosmological mass transport on galactic nuclei and the growth of high-z quasars
(Wiley-VCH Verlag, 2019)
By using cosmological hydrodynamic simulations, we have studied how supernovae (SNe) and active galactic nuclei (AGN) feedback affect the mass transport (MT) process in high-redshift (z ∼ 6) galaxies and what the consequence ...
Detection of neutrinos from micro-quasars i
(World Scientific, 2012-10)
Using the neutrino intensity obtained from models for high-energy particle-emission from low-mass micro-quasars, we calculate the neutrino flux with and without including neutrino oscillations. We show that the neutrino ...
A multi-wavelength survey of AGN in the XMM-LSS field. I. Quasar selection via the KX technique
(2009)
Aims. We present a sample of candidate quasars selected using the KX-technique. The data cover 0.68 deg2 of the X-ray Multi-Mirror (XMM) Large-Scale Structure (LSS) survey area where overlapping multi-wavelength imaging ...