Temperature Profiles of Nearby Clusters of Galaxies
Open Access
- 1 March 2002
- journal article
- research article
- Published by American Astronomical Society in The Astrophysical Journal
- Vol. 567 (1), 163-177
- https://doi.org/10.1086/338378
Abstract
We report results from the analysis of 21 nearby galaxy clusters, 11 with cooling flow (CF) and 10 without cooling flow, observed with BeppoSAX. The temperature profiles of both CF and non-CF systems are characterized by an isothermal core extending out to ~0.2r180; beyond this radius both CF and non-CF cluster profiles rapidly decline. Our results differ from those derived by other authors, who found either continuously declining profiles or substantially flat profiles. Neither the CF nor the non-CF profiles can be modeled by a polytropic temperature profile, the reason being that the radius at which the profiles break is much larger than the core radius characterizing the gas density profiles. For r > 0.2r180, where the gas can be treated as a polytrope, the polytropic indexes derived for CF and non-CF systems are respectively 1.20 ± 0.06 and 1.46 ± 0.06. The former index is closer to the isothermal value, 1, and the latter to the adiabatic value, . Published hydrodynamic simulations do not reproduce the peculiar shape of the observed temperature profile, probably suggesting that a fundamental ingredient is missing.Keywords
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This publication has 49 references indexed in Scilit:
- Effects of Preheating on X‐Ray Scaling Relations in Galaxy ClustersThe Astrophysical Journal, 2001
- ASCA and ROSAT observations of nearby cluster cooling flowsMonthly Notices of the Royal Astronomical Society, 2001
- XMM-Newton observation of the Coma Galaxy clusterAstronomy & Astrophysics, 2001
- Measuring cluster temperature profiles with XMM/EPICAstronomy & Astrophysics, 2001
- A study of the temperature gradient in Virgo/M87 with the MECS on board Beppo-SAXNuclear Physics B - Proceedings Supplements, 1999
- Cluster-subcluster mergers and the formation of narrow-angle tailed radio sourcesMonthly Notices of the Royal Astronomical Society, 1998
- BeppoSAX, the wide band mission for X-ray astronomyAstronomy and Astrophysics Supplement Series, 1997
- The medium-energy concentrator spectrometer on board the BeppoSAX X-ray astronomy satelliteAstronomy and Astrophysics Supplement Series, 1997
- An X‐Ray Temperature Map of Abell 1795, a Galaxy Cluster in Hydrostatic EquilibriumThe Astrophysical Journal, 1996
- An X-ray temperature map of the merging galaxy cluster A2256Nature, 1994