Science-advisor
REGISTER info/FAQ
Login
username
password
     
forgot password?
register here
 
Research articles
  search articles
  reviews guidelines
  reviews
  articles index
My Pages
my alerts
  my messages
  my reviews
  my favorites
 
 
Stat
Members: 3658
Articles: 2'599'751
Articles rated: 2609

02 November 2024
 
  » arxiv » astro-ph/9711083

 Article overview



Deep hard X-ray source counts from a fluctuation analysis of ASCA SIS images
K.C. Gendreau ; X. Barcons ; A.C. Fabian ;
Date 10 Nov 1997
Subject astro-ph
Affiliation2 and 3), A.C. Fabian ( NASA/GSFC USA, IFCA Santander Spain, IoA Cambridge UK
AbstractAn analysis of the spatial fluctuations in 15 deep ASCA SIS0 images has been conducted in order to probe the 2-10 keV X-ray source counts down to a flux limit 2E-14 erg/cm2/s. Special care has been taken in modelling the fluctuations in terms of the sensitivity maps of every one of the 16 regions (5.6 x 5.6 arcmin2 each) in which the SIS0 has been divided, by means of raytracing simulations with improved optical constants in the X-ray telescope. The very extended `side lobes’ (extending up to a couple of degrees) exhibited by these sensitivity maps make our analysis sensitive to both faint on-axis sources and brighter off-axis ones, the former being dominant. The source counts in the range (2-12)E-14 erg/cm2/s are found to be close to a euclidean form which extrapolates well to previous results from higher fluxes and in reasonable agreement with some recent ASCA surveys. However, our results disagree with the deep survey counts by Georgantopoulos et al. (1997). The possibility that the source counts flatten to a subeuclidean form, as is observed at soft energies in ROSAT data, is only weakly constrained to happen at a flux <1.8E-12 erg/cm2/s (90 per cent confidence). Down to the sensitivity limit of our analysis, the integrated contribution of the sources whose imprint is seen in the fluctuations amounts to 35pm 13 per cent of the extragalactic 2-10 keV X-ray background.
Source arXiv, astro-ph/9711083
Services Forum | Review | PDF | Favorites   
 
Visitor rating: did you like this article? no 1   2   3   4   5   yes

No review found.
 Did you like this article?

This article or document is ...
important:
of broad interest:
readable:
new:
correct:
Global appreciation:

  Note: answers to reviews or questions about the article must be posted in the forum section.
Authors are not allowed to review their own article. They can use the forum section.






ScienXe.org
» my Online CV
» Free

home  |  contact  |  terms of use  |  sitemap
Copyright © 2005-2024 - Scimetrica