Dynamics of hot X-ray emitting gas and feedback from galaxies with ASTRO-H

2019 Fiscal Year Final Research Report

• Project/Area Number: 16K05300
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Astronomy
• Research Institution: Tokyo University of Science
• Principal Investigator: Matsushita Kyoko 東京理科大学, 理学部第一部物理学科, 教授 (50366423)
• Project Period (FY): 2016-04-01 – 2020-03-31
• Keywords: 銀河 / 銀河団 / フィードバック / 化学進化 / X線天文学

Outline of Final Research Achievements

We analyze data of the Perseus cluster observed with the Hitomi X-ray satellite. The Perseus cluster is the brightest cluster in the sky, and a suitable target to study feedback from galaxies in the Perseus cluster. We studied the velocity structure, temperature, and metal abundance of the hot gas in the central region of the Perseus cluster of galaxies.
Suzaku has a low background and can detect low surface brightness emission of hot gas in the outer part of the clusters of galaxies. We measured the temperature, density, and Fe abundance of the intracluster medium up to the virial radius of the clusters and groups of galaxies. We studied the entropy, pressure, and density fluctuations in the cluster gas. We discuss the initial mass function of stars in cluster galaxies by determining the total mass of heavy elements.

Free Research Field

X線天文学

Academic Significance and Societal Importance of the Research Achievements

銀河団は宇宙最大の自己重力系であり、暗黒物質の重力で銀河や数千万度の高温ガスを閉じ込めており、バリオンの実験室とも言われる。銀河団銀河は我々の天の川銀河とは異なり楕円銀河が多く、我々の太陽近傍とは異なった進化を辿ってきたように見える。恒星の集団である銀河は我々の天の川銀河のような渦巻銀河と楕円体の楕円銀河が主である。銀河団を観測することにより、２種の銀河における進化の違いを調べることができる。