English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/169899
logo share SHARE logo core CORE   Add this article to your Mendeley library MendeleyBASE

Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Exportar a otros formatos:

Measuring the power spectrum of density fluctuations at intermediate redshift with X-ray background observations

AuthorsBarcons, Xavier ; Fabian, A. C.; Carrera, Francisco J.
KeywordsX-rays: general
Methods: statistical
Large-scale structure of Universe
Diffuse radiation
Issue Date1998
PublisherOxford University Press
CitationMonthly Notices of the Royal Astronomical Society 293(1): 60-70 (1998)
AbstractThe precision of intensity measurements of the extragalactic X-ray background (XRB) on an angular scale of about a degree is dominated by spatial fluctuations caused by source confusion noise. X-ray source counts at the flux level responsible for these fluctuations, ∼10-12 erg cm-2 s-1, will soon be accurately measured by new missions, and it will then be possible to detect the weaker fluctuations caused by the clustering of the fainter, more distant sources which produce the bulk of the XRB. We show here that measurements of these excess fluctuations at the level of (ΔI/I)∼2 × 10-3 are within reach, improving by an order of magnitude on present upper limits. Since it is likely that most (if not all) of the XRB will be resolved into sources by AXAF, subsequent optical identification of these sources will reveal the X-ray volume emissivity in the Universe as a function of redshift. With these ingredients, all-sky observations of the XRB can be used to measure the power spectrum (PS) of the density fluctuations in the Universe at comoving wavevectors kc∼0.01-0.1 Mpc-1 at redshifts where most of the XRB is likely to originate (z∼ 1-2) with a sensitivity similar to, or better than, the predictions from large-scale structure theories. A relatively simple X-ray experiment, carried out by a large-area proportional counter with a 0.5-2 deg2 collimated field of view scanning the whole sky a few times, would be able to determine the PS of the density fluctuations near its expected peak in wavevector with an accuracy better than 10 per cent.
Publisher version (URL)https://doi.org/10.1046/j.1365-8711.1998.01148.x
Identifiersdoi: 10.1046/j.1365-8711.1998.01148.x
issn: 0035-8711
e-issn: 1365-2966
Appears in Collections:(IFCA) Artículos
Files in This Item:
File Description SizeFormat 
measuobser.pdf864,39 kBAdobe PDFThumbnail
Show full item record
Review this work

Related articles:

WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.