Study of the mechanism of massive-star formation by large-scale monitoring survey of methanol masers

2014 Fiscal Year Final Research Report

• Project/Area Number: 24340034
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Astronomy
• Research Institution: Ibaraki University
• Principal Investigator: YONEKURA YOSHINORI 茨城大学, 宇宙科学教育研究センター, 准教授 (90305665)
• Co-Investigator(Renkei-kenkyūsha): MOMOSE Munetake 茨城大学, 理学部, 教授 (10323205) ; FUJISAWA Kenta 山口大学, 時間学研究所, 教授 (70311181) ; SUGIYAMA Koichiro 茨城大学, 宇宙科学教育研究センター, 研究員 (50624954)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 電波天文学 / メタノールメーザー / VLBI / 大質量星形成 / 時間変動

Outline of Final Research Achievements

In order to derive proper motion of materials around massive stars during their formation process, high-angular resolution VLBI observations were achieved toward thirty-six 6.7 GHz methanol maser sources using Japanese and East-Asian VLBI network. We found a rotating disk with expanding motion toward one source.
In order to derive fluctuations in velocity and intensity of 6.7 GHz methanol maser emission, we made single-dish monitoring observations toward 384 6.7 methanol maser sources using Hitachi and Takahagi 32-m radio telescopes. We newly found the following four activities: one source with sinusoidal fluctuation pattern of the intensity, another source with intermittent fluctuation pattern of the intensity, and the other 2 sources with bursting activity.

Free Research Field

電波天文学