Massive star formation across the cosmic time

2015 Fiscal Year Final Research Report

• Project/Area Number: 25800102
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Astronomy
• Research Institution: The University of Tokyo
• Principal Investigator: Hosokawa Takashi 東京大学, 理学(系)研究科(研究院), 助教 (30413967)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 宇宙初代星 / 大質量星 / 銀河形成 / 原始星 / 宇宙初期天体 / 星間物理 / 超巨大ブラックホール

Outline of Final Research Achievements

We have investigated the mass distribution of the first stars with no heavy elements forming in the early universe. In our theoretical study, we have numerically followed a long-term evolution through the early large-scale structure formation, formation and gravitational collapse of primordial gas clouds, until the first stars finally appears after the stellar mass greatly rises via the mass accretion onto tiny embryo protostars. We have dealt with a number of (> 1000 finally) primordial gas clouds, which allows us to examine the statistical properties of the first stars such as their mass distribution. We have also followed the evolution in the late accretion stage where the stellar UV feedback halts the mass accretion to determine the final stellar mass for more than 100 cases. According to our results, the first stars should have had a great diversity in their masses, covering from ~ a few x 10 Msun to ~ 1000 Msun.

Free Research Field

宇宙物理学