| Project/Area Number |
18540234
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Astronomy
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| Research Institution | Niigata University |
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Principal Investigator |
NAKAMURA Fumitaka Niigata University, Institute of Humanities, Social Sciences and Education, Associate Professor (20291354)
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| Project Period (FY) |
2006 – 2007
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| Project Status |
Completed (Fiscal Year 2007)
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| Budget Amount *help |
¥2,640,000 (Direct Cost: ¥2,400,000、Indirect Cost: ¥240,000)
Fiscal Year 2007: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000)
Fiscal Year 2006: ¥1,600,000 (Direct Cost: ¥1,600,000)
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| Keywords | interstellar turbulence / interstellar magnetic field / star formation / binary stars / numerical simulation / molecular cloud / 磁場 / 乱流 / 自己重力 / 星間雲 / 磁気拡散 |
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| Research Abstract |
The purpose of this work is to understand how to form stars, in particular binary stars in turbulent molecular cloud cores. Since binary stars from due to gravitational collapse of molecular cloud cores, it is very important to clarify the physical properties of parent molecular cloud cores. In this study, we fug investigated the formation process of molecular cloud cores from parent turbulent molecular clouds. Star forming molecular clouds are turbulent and magnetized. Thus, we use a three-dimensional magneto-hydrodynamical code to explore the formation of molecular clouds. Our simulations show that molecular cloud cores are formed via turbulent compression from turbulent molecular clouds. The cloud cores so formed tend to have elongated shapes because of external turbulent pressures. Furthermore, shear motions due to turbulent motions remain in the cores. Such shear motions are important for formation of binary stars in such cloud cores. The condition k fragmentation of such cores can be given by the ratio of rotation energy to the gravitational energy and the degree of elongation. The cores formed out of turbulent clouds typically have rotation that is enough k core fragmentation. Thus, binary stars are likely to form very easily from turbulent molecular clouds. In the course of core formation, external turbulent pressures play an important role, and sometimes dominate over the self-gravity.
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