Project/Area Number |
06832011
|
Research Category |
Grant-in-Aid for General Scientific Research (C)
|
Allocation Type | Single-year Grants |
Research Field |
惑星科学
|
Research Institution | KYUSHU UNIVERSITY |
Principal Investigator |
SEKIYA Minoru Kyushu University, Faculty of Science, Associate Professor, 理学部, 助教授 (60202420)
|
Co-Investigator(Kenkyū-buntansha) |
UMEBAYASHI Toyosharu Yamagata University, Faculty of Science, Assistant Professor, 理学部, 助教授 (60183753)
|
Project Period (FY) |
1994 – 1995
|
Project Status |
Completed (Fiscal Year 1995)
|
Budget Amount *help |
¥2,100,000 (Direct Cost: ¥2,100,000)
Fiscal Year 1995: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 1994: ¥1,300,000 (Direct Cost: ¥1,300,000)
|
Keywords | solar system / solar nebula / magnetic field / protoplanetary disk / chondrule / cosmic dust / dust / 原始式惑星系円盤 / ダイナモ |
Research Abstract |
(1) Variation of the dissipation rate of the maganetic field due to the settling and the growth of the dust particles in the solar nebula is calculated. As a result, the dissipation rate of the magnetic field is found to decrease due to the settling and the growth of the dust. However, the magnetic field does not grow as to affect the evolution of the solar nebula. (2) The revision of the momentum transfer rate between an electron and a neutron is found to have little effect on the dissipation rate of the magnetic field. (3) Radiative equilibrium temperature of the solar nebula is calculated. As a result, temperature is found to be lower than of Hayashi's model (1981), and there are possibility that the nebula become unstable against convection even if it is transparent. (4) Numerical code of SPH method to calculate the evolution of the solar nebula due to eddy viscosity is developed. (5) Condition of chondrule formation is made clear, by observing compound chondrules and using the gravitational istability condition of the dust layr. Chondrules were probably made in the region much inner than the Asteroid belt. (6) Chemical reactions and condensation process on the dust particles in the protoplanetary disks are calculated. Especially, behavior of CO molecules are investigated in detail. As a result, it is found that almost all the CO molecules condense for less than 20 K, i. e. outer than 200 AU from the central star. (7) Numerical simulation of the entry of cosmic dust is performed. This simulation give the temperature experienced by a cosmic dust as a function of the entry angle and speed into the atmosphere.
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