Kavli Affiliate: P. C. Joss | Summary:We present model atmospheres and theoretical spectra for X-ray bursters. Our models include the effects of Compton scattering on free electrons. The atmospheres have compositions that are mixtures of hydrogen, helium, and iron. For our models the ratio of color temperature, $T_c$, to effective temperature, $T_eff$, is in the […]
Kavli Affiliate: Edmund Bertschinger | Summary:We report the discovery of a new gravitationally lensed QSO, at a redshift z = 1.689, with four QSO components in a cross-shaped arrangement around a bright galaxy. The maximum separation between images is 2.6 arcsec, enabling a reliable decomposition of the system. Three of the QSO components have g […]
Kavli Affiliate: Michael Zucker | Summary:As the first generation of laser interferometric gravitational wave detectors near operation, research and development has begun on increasing the instrument’s sensitivity while utilizing the existing infrastructure. In the Laser Interferometer Gravitational Wave Observatory (LIGO), significant improvements are being planned for installation in ~2007, increasing strain sensitivity through improved suspensions […]
Kavli Affiliate: Edmund Bertschinger | Summary:The role of the Rossi X-ray Timing Explorer (RXTE) in the study of Gamma-ray Bursts (GRBs) is reviewed. Through April 2001, the All-Sky Monitor (ASM) and the Proportional Counter Array (PCA) instruments have detected 30 GRBs. In 16 cases, an early celestial position was released to the community, sometimes in […]
Kavli Affiliate: Edmund Bertschinger | Summary:Observations with the Rossi X-ray Timing Explorer (RXTE) have led to fundamental progress in the study of compact objects, in particular neutron stars and black holes. In this paper we present briefly some highlights from ~5 years of RXTE operations. | Search Query: arXiv Query: search_query=au:”Bradt Hale”&id_list=&start=0&max_results=10Read More
Kavli Affiliate: Edmund Bertschinger | Summary:A concept for an all-sky monitor mission substantially more powerful than the RXTE ASM is presented in brief. It makes use of 31 Gas Electron Multiplier (GEM) proportional counters to provide continuous monitoring of the entire x-ray sky, except for earth occultations and a small region around the sun. This […]
Kavli Affiliate: Edmund Bertschinger | Summary:Using data from the All-Sky Monitor aboard the Rossi X-ray Timing Explorer (RXTE), we found that the 1.5-12 keV X-ray count rate of Cyg X-1 is, on time scales from 90 seconds to at least 10 days, strongly correlated with the spectral hardness of the source in the soft state, […]
Kavli Affiliate: Edmund Bertschinger | Summary:We present a tabulation of 46 transient x-ray sources monitored with the All-Sky Monitor (ASM) on the Rossi X-ray Timing Explorer (RXTE). They fall into four broad categories: short (~d), intermediate, and long (>500 d) duration of outbursts, and long period binary systems that flare up at periastron (e.g., Be […]
Kavli Affiliate: Edmund Bertschinger | Summary:We present light curves of a sample of "transient" sources observed with the All-Sky Monitor (ASM) of the Rossi X-ray Timing Explorer (RXTE). The light curves extend over 3.5 years. They are presented in three groups: six neutron-star systems, eight black-hole-candidate systems, and an additional diverse set of six objects […]
Kavli Affiliate: Edmund Bertschinger | Summary:X 1908+075 is an optically unidentified and highly absorbed X-ray source that appears in early surveys such as Uhuru, OSO-7, Ariel V, HEAO-1, and the EXOSAT Galactic Plane Survey. These surveys measured a source intensity in the range of 2-12 mCrab at 2-10 keV, and the position was localized to […]