High X-ray-to-optical flux ratio RASS-BSC sources
نویسندگان
چکیده
منابع مشابه
The Hellas2xmm 1df Survey: on the Nature of High X-ray to Optical Flux Ratio Sources
We present results from the photometric and spectroscopic identification of 122 X-ray sources recently discovered by XMM-Newton in the 2-10 keV band (the HELLAS2XMM 1dF sample). One of the most interesting results (which is found also in deeper sourveys) is that ∼ 20% of the sources have an X-ray to optical flux ratio (X/O) ten times or more higher than that of optically selected AGN. Unlike th...
متن کاملIdentification of soft high galactic latitude RASS X-ray sources
We present a summary of spectroscopic identifications of bright soft high galactic latitude X-ray sources from the ROSAT All-Sky Survey with total PSPC count rates 0.11 < CR < 0.5 cts s−1 and hardness ratios HR1 < 0. This study supplements the identification program of a complete sample of sources withCR ≥ 0.5 cts s−1 presented previously. Spectroscopic identifications are presented for 70 of 7...
متن کاملThe Hamburg/RASS Catalogue of optical identifications Northern high-galactic latitude ROSAT Bright Source Catalogue X-ray sources
We present the Hamburg/RASS Catalogue (HRC) of optical identifications of X-ray sources at highgalactic latitude. The HRC includes all X-ray sources from the ROSAT Bright Source Catalogue (RASS-BSC) with galactic latitude |b| ≥ 30◦ and declination δ ≥ 0◦. In this part of the sky covering∼10 000 deg the RASS-BSC contains 5341 X-ray sources. For the optical identification we used blue Schmidt pri...
متن کاملOn the Anticorrelation Between Galaxy Light Concentration and X–ray-to-Optical Flux Ratio
Active Galactic Nuclei (AGN) play an important role in many aspects of the modern cosmology, and of particular interest is the issue of the interplay between AGN and their host galaxy. Using X–ray and optical data sets, we have explored the properties of a large sample of AGNs in the Subaru/XMM-Newton Deep Survey (SXDS) field, and studied their evolution in relation with the evolution of their ...
متن کاملOptical Counterparts of Ultraluminous X-ray Sources
Despite much observational and theoretical effort little is presently known about the nature of the luminous nonnuclear X-ray sources which appear to largely surpass the Eddington limit of a few solar masses. Here we present first results of our OHP/ESO/CFHT optical survey of the environments of variable ultraluminous X-ray sources (ULX) in nearby galaxies. At the position of several ULX we fin...
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: Astronomy and Astrophysics Supplement Series
سال: 1999
ISSN: 0365-0138,1286-4846
DOI: 10.1051/aas:1999448