Diffuse thermal emission from very hot gas in starburst galaxies: Spatial results |
| |
| Institution: | 1. ITeSRE/CNR, via Gobetti 101, 40129 Bologna, Italy;2. Trieste Astronomical Observatory, via G.B. Tiepolo 11, 34131 Trieste, Italy;3. Astronomy Dept., University of Bologna, via Zamboni 33, 40126 Bologna, Italy;4. SISSA/ISAS, via Beirut 2–4, 34013 Trieste, Italy;5. Physics Dept., Southampton University, Southampton SO9 5NH, UK;6. Astronomy Dept., University of Padova, vicolo dell''Osservatorio 5, 35122 Padova, Italy;7. CAISMI/CNR, Largo E.Fermi 5, 50125 Firenze, Italy;8. Astronomy Dept., University of Trieste, via Besenghi, 34131 Trieste, Italy;9. IFCTR/CNR, Via Bassini 15, 20133, Milano, Italy;10. School of Physics and Astronomy, Tel Aviv University, Tel Aviv 69978, Israel;1. Division of Applied Chemistry and Frontier Chemistry Center (FCC), Faculty of Engineering, Hokkaido University, Sapporo, Hokkaido, 060-8628, Japan;2. Institute for Chemical Reaction Design and Discovery (WPI-ICReDD), Hokkaido University, Sapporo, Hokkaido, 060-8628, Japan;1. Department of Chemistry, Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, Lanzhou University, Lanzhou 730000, China;2. National Demonstration Center for Experimental Chemistry Education, Lanzhou University, Lanzhou 730000, China;3. School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China;1. Department of Environmental Engineering, Faculty of Engineering, Giresun University, Giresun, 28200, Turkey;2. Department of Chemistry, Selcuk University, Konya, 42075, Turkey;1. Department of Vascular Surgery, Ambroise Paré University Hospital, AP-HP, Boulogne-Billancourt, France;2. Simone Veil Health Sciences Faculty, University of Versailles Saint-Quentin en Yvelines, Montigny-le-Bretonneux, France;3. Vascular Surgery Unit, Foch Hospital, Suresnes, France;4. Department of Geriatrics, Ambroise Paré University Hospital, AP-HP, Boulogne-Billancourt, France |
| |
| Abstract: | New BeppoSAX observations of the nearby prototypical starburst galaxies NGC 253 and M82 are presented. A companion paper (Cappi et al. 1998) shows that the hard (2–10 keV) spectrum of both galaxies, extracted from the source central regions, is best described by a thermal emission model with kT ∼ 6–9 keV and abundances ∼ 0.1-0.3 solar. The spatial analysis yields clear evidence that this emission is extended in NGC 253, and possibly also in M82. This quite clearly rules out a LLAGN as the main responsible for their hard X-ray emission. Significant contribution from point-sources (i.e. X-ray binaries (XRBs) and Supernovae Remnants (SNRs)) cannot be excluded; neither can we at present reliably estimate the level of Compton emission. However, we argue that such contributions shouldn't affect our main conclusion, i.e., that the BeppoSAX results show, altogether, compelling evidence for the existence of a very hot, metal-poor interstellar plasma in both galaxies. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
