X-rays from hot subdwarfs
نویسندگان
چکیده
منابع مشابه
Disentangling Composite Spectrum Hot Subdwarfs
We give preliminary results from a spectroscopic study of composite spectrum hot subdwarfs (sd+late-type). We obtained spectra of a sample of hot subdwarfs selected from the Catalogue of Spectroscopically Identified Hot Subdwarfs (Kilkenny, Heber, & Drilling 1988) on the basis of near-infrared pho-tometry from the Two Micron All Sky Survey (2MASS). The sample consists of 20 photometric and spec...
متن کاملSpectral Modeling of X-rays from Hot Star Winds
We attempt to determine the mass-loss rates of several O stars using x-ray spectra from Chandra’s archive. Models of x-ray production in hot star winds predict broad, asymmetric emission lines, but observed lines tend to be much more symmetric. Such symmetry can be explained by either lowering the values of the mass-loss rate for these winds, or by reassessing the commonly accepted models of x-...
متن کاملHot subdwarfs from the stable Roche lobe overflow channel
Context. Hot subdwarfs are core-helium-burning stars with extremely thin envelopes. We discuss the formation and evolution of hot subdwarfs formed through the stable Roche lobe overflow (RLOF) channel of intermediate-mass binaries, although their formation channels are various. Aims. In this study, we concentrate on the formation and evolution of hot subdwarfs binaries through the stable RLOF c...
متن کاملModulation of AGN gamma rays by interaction with X-rays from an accretion disk hot spot
We have developed a model for the variability of gamma ray emission in jets of active galactic nuclei in which the variability arises as a result of photon-photon pair production interactions with X-rays emitted by a hot spot in the inner part of the accretion disk. As the hot spot orbits around the central engine, the amount of absorption varies periodically. Our model may account for the obse...
متن کاملDiscovery of magnetic fields in hot subdwarfs
We present initial results of a project to measure mean longitudinal magnetic fields in a group of sdB/OB/O stars. The project was inspired by the discovery of three super-metal-rich sdOB stars, each having metals (e.g. Ti, V) enhanced by factors of 10 3 to 10 5. Similar behaviour is observed in chemically peculiar A stars, where strong magnetic fields are responsible for the enrichment. With t...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Advances in Space Research
سال: 2016
ISSN: 0273-1177
DOI: 10.1016/j.asr.2015.11.022