Results 41 to 50 of about 5,289 (173)
The Origin of the Ultraluminous X-Ray Sources [PDF]
The Astrophysical Journal, 2017 Abstract Recently, several ultraluminous X-ray (ULX) sources were shown to host a neutron star (NS) accretor. We perform a suite of evolutionary calculations, which show that, in fact, NSs are the dominant type of ULX accretor. Although black holes (BH) dominate early epochs after the star-formation burst, NSs outweigh them after a few ...
Wiktorowicz, Grzegorz +3 more
openaire +3 more sources
The Cosmic History of Black Hole Growth from Deep Multiwavelength Surveys
Advances in Astronomy, Volume 2012, Issue 1, 2012., 2012 Significant progress has been made in the last few years on understanding how supermassive black holes form and grow. In this paper, we begin by reviewing the spectral signatures of active galactic nuclei (AGN) ranging from radio to hard X‐ray wavelengths.
Ezequiel Treister +2 more
wiley +1 more source
Classifying the Zoo of Ultraluminous X-ray Sources [PDF]
Chinese Journal of Astronomy and Astrophysics, 2005 Ultraluminous X-ray sources (ULXs) are likely to include different physical types of objects. We discuss some possible subclasses, reviewing the properties of a sample of ULXs recently observed by Chandra and XMM-Newton. Sources with an isotropic X-ray luminosity up to a few times 10^{39} erg/s are consistent with ``normal'' stellar-mass X-ray binaries
Soria, Roberto, Cropper, M., Motch, C.
openaire +3 more sources
Near-infrared counterparts of ultraluminous X-ray sources [PDF]
Monthly Notices of the Royal Astronomical Society, 2014 In this paper we present the results of the first systematic search for counterparts to nearby ultraluminous X-ray sources (ULXs) in the near-infrared (NIR). We observed 62 ULXs in 37 galaxies within 10 Mpc and discovered 17 candidate NIR counterparts.
Heida, M. +10 more
openaire +6 more sources
The Circumnuclear Environment of IRAS 20551‐4250: A Case Study of AGN/Starburst Connection for JWST
Advances in Astronomy, Volume 2012, Issue 1, 2012., 2012 We present a general review of the current knowledge of IRAS 20551‐4250 and its circumnuclear environment. This Ultraluminous Infrared Galaxy is one of the most puzzling sources of its class in the nearby Universe: the near‐IR spectrum is typical of a galaxy experiencing a very intense starburst, but a highly obscured active nucleus is identified ...
E. Sani, E. Nardini, Antonis Georgakakis
wiley +1 more source
OPTICAL COUNTERPARTS OF THE NEAREST ULTRALUMINOUS X-RAY SOURCES [PDF]
The Astrophysical Journal Supplement Series, 2013 ApJS in press. 51 pages; 13 pages of text followed by colour figures and tables. Figure quality reduced to satisfy arXiv regulations, for high quality figure, contact j.c.gladstone@ualberta.ca or download accepted version from ApJS when ...
Gladstone, J.C. +6 more
openaire +4 more sources
A Practical Guide to the Massive Black Hole Cosmic History
Advances in Astronomy, Volume 2012, Issue 1, 2012., 2012 I review our current understanding of massive black hole (MBH) formation and evolution along the cosmic history. After a brief introductory overview of the relevance of MBHs in the hierarchical structure formation paradigm, I discuss the main viable channels for seed BH formation at high redshift and for their subsequent mass growth and spin evolution.
A. Sesana, Francesco Shankar
wiley +1 more source
Stellar-Mass Black Holes and Ultraluminous X-ray Sources [PDF]
Science, 2012 We review the likely population, observational properties, and broad implications of stellar-mass black holes and ultraluminous x-ray sources. We focus on the clear empirical rules connecting accretion and outflow that have been established for stellar-mass black holes in binary systems in the past decade and a half.
R. Fender, T. Belloni
openaire +3 more sources
A bright ultraluminous X-ray source in NGC 5907 [PDF]
Monthly Notices of the Royal Astronomical Society, 2013 We present a multi-mission X-ray analysis of a bright (peak observed 0.3-10 keV luminosity of ~ 6x10^{40} erg s^{-1}), but relatively highly absorbed ULX in the edge-on spiral galaxy NGC 5907. The ULX is spectrally hard in X-rays (Gamma ~ 1.2-1.7, when fitted with an absorbed power-law), and has a previously-reported hard spectral break consistent with
Sutton, A. D. +6 more
openaire +3 more sources
TWO ECLIPSING ULTRALUMINOUS X-RAY SOURCES IN M51 [PDF]
The Astrophysical Journal, 2016 ABSTRACT We present the discovery, from archival Chandra and XMM-Newton data, of X-ray eclipses in two ultraluminous X-ray sources (ULXs), located in the same region of the galaxy M51: CXOM51 J132940.0+471237 (ULX-1, for simplicity) and CXOM51 J132939.5+471244 (ULX-2). Three eclipses were detected for ULX-1 and two for ULX-2.
R. Urquhart, R. Soria
openaire +3 more sources