Astronomy and Astrophysics – Astrophysics
Scientific paper
2003-07-15
Mon.Not.Roy.Astron.Soc.344:L17,2003
Astronomy and Astrophysics
Astrophysics
Five pages, two figures. Accepted for publication in MNRAS letters
Scientific paper
10.1046/j.1365-8711.2003.06963.x
We use archival Chandra X-ray Observatory data to investigate X-ray emission from early-type galaxies in the rich z=0.06 cluster Abell 3128. By combining the X-ray count-rates from an input list of optically-selected galaxies, we obtain a statistical detection of X-ray flux, unbiased by X-ray selection limits. Using 87 galaxies with reliable Chandra data, X-ray emission is detected for galaxies down to M_B ~ -19.0, with only an upper limit determined for galaxies at M_B ~ -18.3. The ratio of X-ray to optical luminosities is consistent with recent determinations of the low-mass X-ray binary content of nearby elliptical galaxies. Taken individually, in contrast, we detect significant (3sigma) flux for only six galaxies. Of these, one is a foreground galaxy, while two are optically-faint galaxies with X-ray hardness ratios characteristic of active galactic nuclei. The remaining three detected galaxies are amongst the optically-brightest cluster members, and have softer X-ray spectra. Their X-ray flux is higher than that expected from X-ray binaries, by a factor 2-10; the excess suggests these galaxies have retained their hot gaseous haloes. The source with the highest L_X / L_B ratio is of unusual optical morphology with prominent sharp-edged shells. Notwithstanding these few exceptions, the cluster population overall exhibits X-ray properties consistent with their emission being dominated by X-ray binaries. We conclude that in rich cluster environments, interaction with the ambient intra-cluster medium acts to strip most galaxies of their hot halo gas.
No associations
LandOfFree
X-ray emission properties of galaxies in Abell 3128 does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with X-ray emission properties of galaxies in Abell 3128, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and X-ray emission properties of galaxies in Abell 3128 will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-312659