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HD 148937: A Multiwavelength Study of the Third Galactic Member of the Of?p Class
Walborn, Nolan R.; Bond, Howard E.; Nazé, Yaël +3 more
Three Galactic O-type stars belong to the rare class of Of?p objects: HD 108, HD 191612, and HD 148937. The first two stars show a wealth of phenomena, including strong X-ray emission, light variability, and dramatic periodic spectral variability. We present here the first detailed optical and X-ray study of the third Galactic Of?p star, HD 148937…
Source Matching in the SDSS and Rass: which Galaxies are Really X-Ray Sources?
Hoyle, Fiona; Parejko, John K.; Constantin, Anca +1 more
The current view of galaxy formation holds that all massive galaxies harbor a massive black hole at their center, but that these black holes are not always in an actively accreting phase. X-ray emission is often used to identify accreting sources, but for galaxies that are not harboring quasars (low-luminosity active galaxies), the X-ray flux may …
Variable X-Ray Absorption Toward the Gravitationally-Lensed Blazar PKS 1830-211
Garmire, Gordon P.; Mathur, Smita; Dai, Xinyu +2 more
We present X-ray spectral analysis of five Chandra and XMM-Newton observations of the gravitationally-lensed blazar PKS 1830-211 from 2000 to 2004. We show that the X-ray absorption toward PKS 1830-211 is a variable, and the variable absorption is most likely to be intrinsic with amplitudes of ~2 × 1022 30 × 1022 cm-2
The XMM-Newton X-Ray Emission of the Supernova Remnant N 120 in the Large Magellanic Cloud
Rosado, Margarita; Reyes-Iturbide, Jorge; Velázquez, Pablo F.
We present new XMM-Newton observations of the supernova remnant (SNR) N 120 in the Large Magellanic Cloud, and numerical simulations on the evolution of this SNR which we compare with the X-ray observations. The SNR N 120, together with several H II regions, forms a large nebular complex (also called N 120) whose shape resembles a semicircular rin…