Please use this identifier to cite or link to this item: http://hdl.handle.net/1959.3/1855

Download PDF (Author's final draft) (Adobe Acrobat PDF, -1 bytes)

Title

A catalogue and analysis of X-ray luminosities of early-type galaxies

Author(s)

O'Sullivan, Ewan;  Forbes, Duncan A.;  Ponman, Trevor

Abstract

We present a catalogue of X-ray luminosities for 401 early-type galaxies, of which 136 are based on newly analysed ROSAT PSPC pointed observations. The remaining luminosities are taken from the literature and converted to a common energy band, spectral model and distance scale. Using this sample we fit the LX:LB relation for early-type galaxies and find a best-fit slope for the catalogue of ~2.2. We demonstrate the influence of group-dominant galaxies on the fit and present evidence that the relation is not well modelled by a single power-law fit. We also derive estimates of the contribution to galaxy X-ray luminosities from discrete-sources and conclude that they provide Ldscr/LB~=29.5ergs-1LBsolar-1. We compare this result with luminosities from our catalogue. Lastly, we examine the influence of environment on galaxy X-ray luminosity and on the form of the LX:LB relation. We conclude that although environment undoubtedly affects the X-ray properties of individual galaxies, particularly those in the centres of groups and clusters, it does not change the nature of whole populations.

Publication type

Journal article

Research centre

Swinburne University of Technology. Centre for Astrophysics and Supercomputing

Source

Monthly Notices of the Royal Astronomical Society, Vol. 328, no. 2 (Dec 2001), pp. 461-484

Publication year

2001

Keyword(s)

Elliptical galaxies;  Lenticular galaxies;  Surveys;  X-rays

Publisher

Blackwell Publishing

ISSN

0035-8711

Publisher URL

http://dx.doi.org/10.1046/j.1365-8711.2001.04890.x

Copyright

Copyright © 2001 The Royal Astronomical Society. Author's final draft reproduced here in accordance with the copyright policy of the publisher.

Full text

Peer reviewed