202 citations · 2.2k across the 37 of their papers we have counts for
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Galactic Globular Clusters with Luminous X-Ray Binaries
Joel N. Bregman
Luminous X-ray binaries (>1E34 erg/s, LMXBs) have a neutron star or black hole primary, and in globular clusters, most of these close binaries are expected to be have evolved from…
Radial velocities in the globular cluster omega Centauri
R. A. Reijns, P. Seitzer, R. Arnold +5
We have used the ARGUS multi-object spectrometer at the CTIO 4m Blanco telescope to obtain 2756 radial velocity measurements for 1966 individual stars in the globular cluster omega…
Elemental Abundance Ratios in Stars of the Outer Galactic Disk. II. Field Red Giants
Bruce W. Carney, David Yong, Luisa de Almeida +1
We summarize a selection process to identify red giants in the direction of the southern warp of the Galactic disk, employing VI_C photometry and multi-object spectroscopy. We also…
Optical studies of ultra-luminous X-ray sources in nearby galaxies
Ji-Feng Liu, Joel N. Bregman, Patrick Seitzer +1
Optical studies of ultra-luminous X-ray sources is an essential step in understanding the nature of these enigmatic sources, and in this paper we report our studies of five ULXs in…
A Two Hour Quasi-Period in an Ultra-luminous X-Ray source in NGC628
Ji-Feng Liu, Joel N. Bregman, Ed Lloyd-Davies +3
Quasi-periodic oscillations and X-ray spectroscopy are powerful probes of black hole masses and accretion disks, and here we apply these diagnostics to an ultraluminous X-ray sourc…
The optical counterpart of an Ultra-luminous X-Ray Source in NGC 5204
Ji-Feng Liu Joel N. Bregman, Patrick Seitzer
Ultra-luminous X-Ray sources are extra-nuclear point sources in external galaxies with -- erg/s and are among the most poorly understood X-ray sources. To hel…