| タイトル | High-Energy Properties of the Enigmatic Be Star Gamma Cassiopeiae |
| 本文（外部サイト） | http://hdl.handle.net/2060/20150015984 |
| 著者（英） | Sturner, S. J.; Almeyda, T.; Shrader, C. R.; Hamaguchi, K.; Petre, R.; Oskinova, L. M. |
| 著者所属（英） | NASA Goddard Space Flight Center |
| 発行日 | 2015-01-19 |
| 言語 | eng |
| 内容記述 | We present the results of a broadband X-ray study of the enigmatic Be star Gamma Cassiopeiae (herein gamma Cas) based on observations made with both the Suzaku and INTEGRAL observatories. Gamma Cas has long been recognized as the prototypical example of a small subclass of Be stars with moderately strong X-ray emission dominated by a hot thermal component in the 0.5 - 12 keV energy range (L(sub x) approximately equals 10(exp 32) - 10(exp 33) erg per s). This places them at the high end of the known luminosity distribution for stellar emission, but several orders of magnitude below typical accretion-powered Be X-ray binaries. The INTEGRAL observations spanned an eight-year baseline and represent the deepest measurement to date at energies above approximately 50 keV. We find that the INTEGRAL data are consistent within statistics to a constant intensity source above 20 keV, with emission extending up to approximately 100 keV, and that searches for all of the previously reported periodicities of the system at lower energies led to null results. We further find that our combined Suzaku and INTEGRAL spectrum, which we suggest is the most accurate broadband X-ray measurement of gamma Cas to date, is fitted extremely well with a thermal plasma emission model with a single absorption component. We found no compelling need for an additional non-thermal high-energy component. We discuss these results in the context of a currently favored models for gamma Cas and its analogs. |
| NASA分類 | Instrumentation and Photography; Astronomy |
| レポートNO | GSFC-E-DAA-TN24046 |
| 権利 | Copyright, Distribution as joint owner in the copyright |
| URI | https://repository.exst.jaxa.jp/dspace/handle/a-is/558333 |
