EDP Sciences Journals List
Advanced Search
Subscriber Authentication Point
Home All issues Volume 392/3 Article
Free access article

Issue A&A
Volume 392, Number 3, September IV 2002
Page(s) 885 - 893
Section Formation, structure and evolution of stars
DOI http://dx.doi.org/10.1051/0004-6361:20020707



A&A 392, 885-893 (2002)
DOI: 10.1051/0004-6361:20020707

BeppoSAX Wide Field Cameras observations of six type I X-ray bursters

R. Cornelisse1, 2, F. Verbunt2, J. J. M. in 't Zand2, 1, E. Kuulkers1, 2, J. Heise1, R. A. Remillard3, M. Cocchi4, L. Natalucci4, A. Bazzano4 and P. Ubertini4

1  SRON National Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
2  Astronomical Institute, Utrecht University, PO Box 80000, 3508 TA Utrecht, The Netherlands
3  Center for Space Research, Massachusetts Institute of Technology, Cambridge, MA 02139-4307, USA
4  Istituto di Astrofisica Spaziale (CNR), Area Ricerca Roma Tor Vergata, Via del Fosso del Cavaliere, 00133 Roma, Italy

(Received 7 November 2001 / Accepted 15 May 2002 )

Abstract
We have discovered three certain (SAX J1324.5-6313, 2S 1711-339 and SAX J1828.5-1037) and two likely (SAX J1818.7+1424 and SAX J2224.9+5421) new thermonuclear X-ray burst sources with the BeppoSAX Wide Field Cameras, and observed a second burst ever from a sixth one (2S 0918-549). Four of them (excluding 2S 1711-339 and 2S 0918-549) are newly detected X-ray sources from which we observed single bursts, but no persistent emission. We observe the first 11 bursts ever from 2S 1711-339; persistent flux was detected during the first ten bursts, but not around the last burst. A single burst was recently detected from 2S 0918-549 by Jonker et al. (2001); we observe a second burst showing radius expansion, from which a distance of 4.2 kpc is derived. According to theory, bursts from very low flux levels should last $\gtrsim$100 s. Such is indeed the case for the last burst from 2S 1711-339, the single burst from SAX J1828.5-1037 and the two bursts from 2S 0918-549, but not for the bursts from SAX J1324.5-6313, SAX J1818.7+1424 and SAX J2224.9+5421. The bursts from the latter sources all last ~20 s. We suggest that SAX J1324.5-6313, SAX J1818.7+1424, SAX J1828.5-1037 and SAX J2224.9+5421 are members of the recently proposed class of bursters with distinctively low persistent flux levels, and show that the galactic distribution of this class is compatible with that of the standard low-mass X-ray binaries.


Key words: accretion, accretion disks -- binaries: close -- stars: individual: SAX J1324.5-6313, SAX J1818.7+1424, SAX J1828.5-1037, SAX J2224.9+5421, 2S 1711-339, 2S 0918-549 -- stars: neutron -- X-rays: bursts

Offprint request: R. Cornelisse, R.Cornelisse@sron.nl

SIMBAD Objects in preparation



© ESO 2002


What is OpenURL?

The OpenURL standard is a protocol for transmission of metadata describing the resource that you wish to access. An OpenURL link contains article metadata and directs it to the OpenURL server of your choice. The OpenURL server can provide access to the resource and also offer complementary services (specific search engine, export of references...). The OpenURL link can be generated by different means.
  • If your librarian has set up your subscription with an OpenURL resolver, OpenURL links appear automatically on the abstract pages.
  • You can define your own OpenURL resolver with your EDPS Account. In this case your choice will be given priority over that of your library.
  • You can use an add-on for your browser (Firefox or I.E.) to display OpenURL links on a page (see http://www.openly.com/openurlref/). You should disable this module if you wish to use the OpenURL server that you or your library have defined.