Project/Area Number |
05833001
|
Research Category |
Grant-in-Aid for General Scientific Research (C)
|
Allocation Type | Single-year Grants |
Research Field |
惑星科学
|
Research Institution | Nagoya University |
Principal Investigator |
WATANABE Sei-ichiro Nagoya Univ., Sciences, Assistant Professor, 理学部, 助手 (50230967)
|
Project Period (FY) |
1993 – 1994
|
Project Status |
Completed (Fiscal Year 1994)
|
Budget Amount *help |
¥2,200,000 (Direct Cost: ¥2,200,000)
Fiscal Year 1994: ¥600,000 (Direct Cost: ¥600,000)
Fiscal Year 1993: ¥1,600,000 (Direct Cost: ¥1,600,000)
|
Keywords | Formation of Solar System / Protoplanetary Disk / Solar Nebula / Turbulence / Dust Grain / Bipolar Outflow / Planetary Accumulation / 微惑星 / 固体微粒子 / 惑星形成論 |
Research Abstract |
We have investigated the growth of dust in the turbulent solar nebula, from which our solar system had formed. We found that optical jets which blow from the inner edge of the disk play the following important role. The optical jets are magnetocentrifugally driven winds that are accelerated by the rotatiog magnetic field of the protosun. Dust which move inward in the disk by passing their angular momentum to the surronding gas concentrate near the X region (where gas corotates with the protosun). The temperature at the X region is about 1500 K,so that the dust partially evaporate there. Some of the dust can be lifted by the aerodynamic drag of the optical jets. Then, the size-sorting mechanism works : the grains with their radius smaller than about 1 cm will be lifted up and those with radius larger than a few mu m will reentry to the disk. Radiuses of the reentry depend on the dust sizes and wind velocities. Dust colls rapidly in the jets without collisional sticking. The scenario of the dust formation is consistent with the size distribution, natural remanent magnetization, and evapolational metamorphism of CAIs and chondrules in the primitive meteorites, as well as mechanical mixing of high-temperature condensates with low-temperate matrix.
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