Issue |
A&A
Volume 459, Number 2, November IV 2006
|
|
---|---|---|
Page(s) | 415 - 422 | |
Section | Extragalactic astronomy | |
DOI | https://doi.org/10.1051/0004-6361:20065681 | |
Published online | 12 September 2006 |
Discovery of a cluster of galaxies behind the Milky Way: X-ray and optical observations
1
Instituto de Astronomia, Geofísica e Ciências Atmosféricas, Universidade de São Paulo, R. do Matão 1226, 05508-900 São Paulo, Brazil e-mail: rlopes@astro.iag.usp.br
2
Observatoire Astronomique, UMR 7550 CNRS, 11 rue de l'Université, 67000 Strasbourg, France
Received:
23
May
2006
Accepted:
12
July
2006
We report the discovery of Cl 2334+48, a rich cluster of galaxies in the Zone of
Avoidance, identified in public images from the XMM-Newton archive.
We present the main properties of this cluster using the XMM-Newton
X-ray data, along with new optical spectroscopic and photometric observations. Cl 2334+48
is located at ± 0.001, as derived from the optical spectrum of
the brightest member galaxy. Such redshift agrees with a determination from
the X-ray spectrum (z = 0.263
), in which an intense
emission line is matched to the rest wavelength of the Fe Kα complex.
Its intracluster medium has a plasma temperature of
keV,
a sub-solar abundance of 0.38 ±
, and a bolometric
luminosity of 3.2
1044 erg s-1. A density contrast
is reached in a radius of
Mpc, and the corresponding
enclosed mass is 1.5
. Optical images show an enhancement of
galaxies around the central
galaxy, as expected if these were cluster members. The central object is a luminous E-type galaxy, which is displaced ~
kpc from the
cluster X-ray centre. In addition, it has a neighbouring arc-like feature
(~
or
kpc from it), probably due to strong
gravitational lensing. The discovery of Cl 2334+48 emphasises the remarkable
capability of the XMM-Newton to reveal new clusters of galaxies in
the Zone of Avoidance.
Key words: galaxies: clusters: individual: XMMU J233402.7+485108 / galaxies: intergalactic medium / X-ray: galaxies: clusters
© ESO, 2006
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.