Energetic contribution of X-ray binaries to diffuse X-ray emission in the Galactic center

2014 Fiscal Year Final Research Report

• Project/Area Number: 24740133
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Astronomy
• Research Institution: Nagoya University (2013-2014); Japan Aerospace Exploration Agency (2012)
• Principal Investigator: MORI Hideyuki 名古屋大学, 現象解析研究センター, 助教 (20432354)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 銀河系バルジ / 低質量X線連星系 / 銀河団 / X線星 / 未同定X線天体 / X線光度関数

Outline of Final Research Achievements

We constructed the luminosity function of the Low-Mass X-ray Binaries (LMXBs) in the Galactic bulge, which is a fundamental observable to elucidate the formation history of the Galaxy, using a flux-limited sample extracted from the ROSAT All-Sky Survey. In order to improve the completeness of the luminosity function, Spectroscopic studies above 2 keV were performed for unidentified X-ray sources towards the Galactic bulge; 13 follow-up X-ray observations were carried out with Suzaku and Chandra. We have almost completed the observations of these unidentified bulge sources, and then obtained good-quality hard (> 2keV) X-ray spectra. So far we newly identified 1 LMXB, 2 clusters of galaxies, and 3 X-ray active stars. These result suggests that the number of the LMXBs in the Galactic bulge is smaller than those in the bulges of other disk galaxies and elliptical galaxies.

Free Research Field

X線天文学