Paper: astro-ph/0509433
Date: Thu, 15 Sep 2005 10:21:36 GMT (177kb)

Title: Discovery of a bright quasar without a massive host galaxy

Authors: Pierre Magain (1), Geraldine Letawe (1), Frederic Courbin (2), Pascale
Jablonka (2,3), Knud Jahnke (4), Lutz Wisotzki (4), Georges Meylan (2) ((1)
Univ. de Liege, Belgium (2) EPFL Switzerland (3) Univ. de Geneve, Switzerland
(4) AIPotsdam, Germany)

Comments: 5 figures, published in Nature

Journal-ref: Nature, 473, 15 sept 2005, pp381-384
\\
Quasars are thought to be powered by the infall of matter onto a supermassive
black hole at the centre of massive galaxies. As the optical luminosity of
quasars exceeds that of their host galaxy, disentangling the two components can
be difficult. This led in the 1990's to the controversial claim of the
discovery of 'naked' quasars. Since then, the connection between quasars and
galaxies has been well established. Here we report on the observation of a
quasar lying at the edge of a gas cloud, whose size is comparable to that of a
small galaxy, but whose spectrum shows no evidence for stars. The gas cloud is
excited by the quasar itself. If a host galaxy is present, it is at least six
times fainter than would normally be expected for such a bright quasar. The
quasar is interacting dynamically with a neighbouring galaxy - which matter
might be feeding the black hole.

\\ ( http://arXiv.org/abs/astro-ph/0509433 , 177kb)