Quick Search:

is currently disabled due to reindexing of the ZORA database. Please use Advanced Search.
uzh logo
Browse by:
bullet
bullet
bullet
bullet

Zurich Open Repository and Archive 

Permanent URL to this publication: http://dx.doi.org/10.5167/uzh-17015

Mapelli, M; Moore, B; Giordano, L; Mayer, L; Colpi, M; Ripamonti, E; Callegari, S (2008). Intermediate-mass black holes and ultraluminous X-ray sources in the Cartwheel ring galaxy. Monthly Notices of the Royal Astronomical Society, 383(1):230-246.

[img]
Preview
Accepted Version
PDF (Accepted manuscript, Version 2)
1MB
[img]
Preview
Accepted Version
PDF (Accepted manuscript, Version 1)
634kB

Abstract

Chandra and XMM–Newton observations of the Cartwheel galaxy show ∼17 bright X-ray sources (≳5 × 1038 erg s−1) , all within the gas-rich outer ring. We explore the hypothesis that these X-ray sources are powered by intermediate-mass black holes (IMBHs) accreting gas or undergoing mass transfer from a stellar companion. To this purpose, we run N-body/smoothed particle hydrodynamics simulations of the galaxy interaction which might have led to the formation of Cartwheel, tracking the dynamical evolution of two different IMBH populations: halo and disc IMBHs. Halo IMBHs cannot account for the observed X-ray sources, as only a few of them cross the outer ring. Instead, more than half of the disc IMBHs are pulled in the outer ring as a consequence of the galaxy collision. However, also in the case of disc IMBHs, accretion from surrounding gas clouds cannot account for the high luminosities of the observed sources. Finally, more than 500 disc IMBHs are required to produce ≲15 X-ray sources via mass transfer from very young stellar companions. Such number of IMBHs is very large and implies extreme assumptions. Thus, the hypothesis that all the observed X-ray sources in Cartwheel are associated with IMBHs is hardly consistent with our simulations, even if it is still possible that IMBHs account for the few (≲1–5) brightest ultraluminous X-ray sources.

Item Type:Journal Article, refereed, original work
Communities & Collections:07 Faculty of Science > Institute for Computational Science
DDC:530 Physics
Language:English
Date:January 2008
Deposited On:10 Mar 2009 19:23
Last Modified:28 Nov 2013 00:59
Publisher:Wiley-Blackwell
ISSN:0035-8711
Additional Information:The definitive version is available at www.blackwell-synergy.com
Publisher DOI:10.1111/j.1365-2966.2007.12534.x
Related URLs:http://arxiv.org/abs/0710.0780
Citations:Web of Science®. Times Cited: 18
Google Scholar™
Scopus®. Citation Count: 18

Users (please log in): suggest update or correction for this item

Repository Staff Only: item control page