伽玛暴(Gamma-Ray Burst)笔记。记录有关伽玛暴的新文章,另外也包括看的老文章、自己的想法、以及跟天文相关的一些东西。 Feel free to leave me a message by comments or by email.

星期二, 六月 03, 2008

Casandjian 2008 Compton EGRET 高能源的catalogue的修正版

主要内容:
有188个源,比3rd catalogue的源减少了100来个,发现不是的。

精彩摘抄:


文章信息:

arXiv:0806.0113 [ps, pdf, other]
Title: A revised catalogue of EGRET gamma-ray sources
Comments: Accepted in A&A Full resolution figures and ASCII tables can be downloaded from: this http URL
Subjects: Astrophysics (astro-ph)

We present a catalog of point gamma-ray sources detected by the EGRET detector aboard the Compton Gamma Ray Observatory. We have used the whole gamma-ray dataset of reprocessed photons at energies above 100 MeV together with new Galactic interstellar emission models based on recent CO, HI, dark gas, and interstellar radiation field data. Two different assumptions have been used for the cosmic-ray distribution in the Galaxy to explore the resulting systematic uncertainties in source detection and characterization. We have used the same 2-dimensional maximum-likelihood detection method as for the 3rd EGRET catalogue. The revised catalogue lists 188 sources, 14 of which are marked as confused, compared to the 271 entries of the 3rd EGRET (3EG) catalogue. 107 former sources have not been confirmed because of the additional structure in the interstellar background. The vast majority of them were unidentified and marked as possibly extended or confused in the 3EG catalogue. In particular, we do not confirm most of the 3EG sources associated with the local clouds of the Gould Belt. Alternatively, we find 30 new sources with no 3EG counterpart. The new error circles for the confirmed 3EG sources largely overlap the previous ones, but several counterparts of particular interest that had been discussed in the litterature, such as Sgr A*, radiogalaxies and several microquasars are now found outside the error circles. We have cross-correlated the source positions with a large number of radio pulsars, pulsar wind nebulae, supernova remnants, OB associations, blazars and flat radiosources and we find a surprising large number of sources (87) at all latitudes with no counterpart among the potential gamma-ray emitters.

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