Study of energy budget in the evolution of galaxy clusters

2015 Fiscal Year Final Research Report

• Project/Area Number: 25400231
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Astronomy
• Research Institution: Nara Women's University
• Principal Investigator: Ota Naomi 奈良女子大学, 自然科学系, 准教授 (40391891)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: Ｘ線天文学 / 宇宙物理学 / 銀河団 / 高温プラズマ / 衝突合体現象 / 非熱的放射 / 乱流 / 宇宙構造形成

Outline of Final Research Achievements

Clusters of galaxies grow into the present shape via collisions and mergers of smaller objects. If clusters collide with each other, a huge amount of kinetic energy may be released and a certain fraction is expected to heat the gas and generate high-energy particles, and induce bulk and turbulent motions. To reveal the energy budget in the cluster evolution, we constrained the existence of very hot/non-thermal gas in clusters using the Suzaku satellite. From a systematic search for gas motions, we discovered the sign of large bulk motions in both regular and irregular clusters and a significant offset between the spatial distributions of gas and galaxies. Furthermore, we carried out simulations of spectral observations using high-resolution X-ray calorimeter onboard the ASTRO-H satellite and showed a possibility that we can measure the turbulent gas motion and the cluster mass with high accuracy.

Free Research Field

Ｘ線天文学