A study of the solar modulation of galactic cosmic rays and the origin of cosmic particles and anti-particles using stochastic differential equations
Project/Area Number |
19540260
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Research Category |
Grant-in-Aid for Scientific Research (C)
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Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Particle/Nuclear/Cosmic ray/Astro physics
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Research Institution | Ibaraki University |
Principal Investigator |
YANAGITA Shohei Ibaraki University, 理学部, 教授 (40013429)
|
Co-Investigator(Kenkyū-buntansha) |
YAMAMOTO Akira 大学共同利用機関法人高エネルギー加速器研究所, 共通基盤施設, 教授 (30113418)
|
Research Collaborator |
MIYAKE Shoko 茨城県立医療大学, 保健医療学部, 嘱託助手
|
Project Period (FY) |
2007 – 2009
|
Project Status |
Completed (Fiscal Year 2009)
|
Budget Amount *help |
¥3,770,000 (Direct Cost: ¥2,900,000、Indirect Cost: ¥870,000)
Fiscal Year 2009: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000)
Fiscal Year 2008: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000)
Fiscal Year 2007: ¥2,210,000 (Direct Cost: ¥1,700,000、Indirect Cost: ¥510,000)
|
Keywords | 宇宙線 / 太陽変調 / 反陽子 / 確率微分方程式 / 太陽圏 / 惑星間空間磁場 / PLD / galactic cosmic rays / solar modulation / antiproton / 銀河宇宙線 |
Research Abstract |
We have built models of heliospheric magnetic field (HMF) corresponding to Parker-type and Fisk-type HMF including resultant current sheets. We have developed a fully 3D simulation code based on a coupled stochastic differential equations which allows us to investigate charge dependence of the solar modulation of galactic cosmic rays. The 22-year periodicity of the intensity of protons was reproduced nicely, however, we failed in reproducing quantitatively the time variation of the anti-proton to proton ratios. The energy dependence of positron to electron ratios observed by BESS and PAMELA experiment during different polarity of HMF is reproduced well by our model with Fisk-type HMF.
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Report
(4 results)
Research Products
(18 results)