首页>
外文期刊>The Astrophysical journal
>Rossi X-Ray Timing Explorer Hard X-Ray Observation of A754: Constraining the Hottest Temperature Component and the Intracluster Magnetic Field
【24h】
Rossi X-Ray Timing Explorer Hard X-Ray Observation of A754: Constraining the Hottest Temperature Component and the Intracluster Magnetic Field
Abell 754, a cluster undergoing merging, was observed in hard X-rays with the Rossi X-Ray Timing Explorer (RXTE) in order to constrain its hottest temperature component and search for evidence of nonthermal emission. Simultaneous modeling of RXTE data and those taken with previous missions yields an average intracluster temperature of ~9 keV in the 1-50 keV energy band. A multitemperature component model derived from numerical simulations of the evolution of a cluster undergoing a merger produces similar quality of fit, indicating that the emission measure from the very hot gas component is sufficiently small that it renders the two models indistinguishable. No significant nonthermal emission was detected. However, our observations set an upper limit of 7.1×10?14 ergs cm?2 s?1 keV?1 (90% confidence limit) to the nonthermal emission flux at 20 keV. Combining this result with the radio synchrotron emission flux, we find a lower limit of 0.2 μG for the intracluster magnetic field. We discuss the implications of our results for the theories of magnetic field amplifications in cluster mergers.
展开▼
