THEORETICAL STUDIES ON HIGH ENERGY ASTROPHYSICS

高能天体物理理论研究

• 批准号: 13440061
• 负责人: TAKAHARA Fumio
• 金额: $ 3.14万
• 依托单位: Osaka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-13440061/
• 关键词: accretion disks; relativistic jets; gamma ray bursts; active galaxies; particle acceleration; black holes; clusters of galaxies; astrophysical plasmas

During the three year term of this project, each member has done research on individual subjects and published many papers. For each year a research meeting was held to boost mutual understanding of common concepts and physical processes, and interrelations among various high-energy astrophysical objects. Major achievements are as follows :1. The role of magnetic fields in. accretion disks has been investigated through large scale numerical simulations. Their behavior in impinging into the black hole and effect on time variations in X-ray emission was clarified. A possibility of making a magnetic tower was also suggested.2. The Wien fireball model for the formation of relativistic jets was quantitatively investigated through the Monte Carlo simulation of radiation hydrodynamics. Analysis of the physical state of jets was also made based on multi-frequency observational data.3. The spatial size of the region where particle acceleration is occurring in SNR SN1006 and RXJ1713.7 was found to be extremely small and strong constraints on diffusive acceleration were obtained. Electron acceleration process through surfing mechanism utilizing microscopic electric field structure associated with collisionless shocks was clarified through numerical simulation.

在该项目的三年任期内，每位成员都对各自的课题进行了研究并发表了多篇论文。每年都会举行一次研究会议，以促进对共同概念和物理过程以及各种高能天体物理物体之间相互关系的相互理解。主要成果如下： 1．磁场在吸积盘中的作用已通过大规模数值模拟进行了研究。它们撞击黑洞的行为以及对 X 射线发射时间变化的影响得到了澄清。还提出了制作磁塔的可能性。 2．通过辐射流体动力学的蒙特卡罗模拟定量研究了相对论性喷流形成的维恩火球模型。基于多频观测数据，对喷流的物理状态进行了分析。 3．发现 SNR SN1006 和 RXJ1713.7 中发生粒子加速的区域的空间尺寸非常小，并且获得了对扩散加速度的强约束。通过数值模拟阐明了利用与无碰撞冲击相关的微观电场结构的冲浪机制的电子加速过程。

项目成果

Yamazaki, Ryo: "X-Ray Flashes from Off-Axis Gamma-Ray Bursts"The Astrophysical Journal. 571 1. L31-L35 (2002)

山崎亮：“离轴伽马射线爆发产生的 X 射线闪光”《天体物理学杂志》。

Takahashi, R.: "Microlens of Bright Quasars"PASJ. 53. 387-393 (2001)

Takahashi, R.：“明亮类星体的微透镜”PASJ。

S.Nagataki: "Explosive Nucleosynthesis Associated with Formation of Jet-induced Gamma-Ray Bursts in Mass"Astrophysical Journal. 596. 401-413 (2003)

S.Nagataki：“与喷射引起的伽马射线爆发相关的爆炸性核合成”天体物理学杂志。

Wang, J.-M.: "Blob Ejection from Advection-dominated Accretion Flow. II. The Multiwavelength Properties of Light Curves"Astrophysical Journal, Supplement Series. 138. 249-263 (2002)

Wang, J.-M.：“平流主导吸积流中的斑点喷射。II.光曲线的多波长特性”天体物理学杂志，增刊系列。

Watarai, K.: "Slim Disk : Viscosity Prescriptions and Observational Implications"PASJ. 53. 915-921 (2001)

Watarai, K.：“细盘：粘度处方和观察意义”PASJ。