A&A 483, 15-18 (2008)
DOI: 10.1051/0004-6361:20077797
Testing power-law cosmology with galaxy clusters
Zong-Hong Zhu1, 2, M. Hu1, J. S. Alcaniz3, 4, and Y.-X. Liu51 Department of Astronomy, Beijing Normal University, Beijing 100875, PR China
e-mail: zhuzh@bnu.edu.cn
2 Institut d'Astrophysique Spatiale (IAS), CNRS & Univ. Paris-Sud, Bâtiment 121, 91405 Orsay, France
3 Departamento de Astronomia, Observatório Nacional, 20921-400, Rio de Janeiro, Brasil
e-mail: alcaniz@on.br
4 Instituto Nacional de Pesquisas Espaciais/CRN, 59079-740, Natal-RN, Brazil
5 The College of Applied Science, Beijing University of Technology, Beijing 100022, PR China
(Received 5 May 2007 / Accepted 20 December 2007)
Abstract
Aims.
Power-law cosmologies, in which the cosmological
scale factor evolves as a power law in time, with , regardless of the
matter content or cosmological epoch, is comfortably
concordant with a host of cosmological
observations.
Methods. In this article, we use
recent measurements of the X-ray gas mass fractions in
clusters of galaxies to constrain the parameter with
curvature .
Results. We
find that the best fit happens for an open scenario with
the power index 0.05, though the flat
and closed model cannot be ruled out with high
confidence.
Conclusions. Our results are in
agreement with other recent analyses and show that the
X-ray gas mass fraction measurements in clusters of
galaxies provide a complementary test of the power-law
cosmology.
Key words: cosmological parameters -- cosmology: theory -- X-rays: galaxies: clusters
© ESO 2008