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Extraction of Rotation Energy from a Black Hole. Kyoto University ( YITP ) S. Nagataki. 18 th July 2007, YITP. Gamma-Ray Bursts ~ the most powerful explosion in the universe ~. Image of GRB 970228 by HST. Some GRBs are known to be associated with hypernova explosions
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Extraction of Rotation Energy from a Black Hole Kyoto University (YITP) S. Nagataki 18th July 2007, YITP
Gamma-Ray Bursts ~the most powerful explosion in the universe~ Image of GRB970228 by HST Some GRBs are known to be associated with hypernova explosions whose explosion energy is 10^52 erg. = 10 times larger than the explosion energy of a supernova explosion. = 10 times larger than the energy emitted from the sun in its whole life. = 10^31 times larger than the atomic bomb dropped on Hiroshima. Feb28th 1997 Mar3rd 1997 Explosion mechanism is still unknown.
Hypernova Explosion Its spectrum is similar to that of a core-collapse supernova (death of a massive star). Hypernova will be also associated with death of a (very) massive star. In a core-collapase supernova, a neutron Star is formed at the center. In a hypernova, a black hole is formed At the center? GRB030329 / SN2003dh
Extraction of Rotation Energy from a Black Hole (BZ effect)? I’m going to study BZ effect numerically. For any stationary system, we can define conserved flux vector for energy. It’s an interesting project! = Axisymmetry Const. Rotation Energy of a central BH If an appropriate Tmunu is put around a BH, energy can be extracted from the BH. Roger and Me 2005, Banff, Canada. Blandford and Znajek (1977)
Numerical simulation of Blandford-Znajek Process Numerical results for energy flux with various a. T=200, c=G=M=1 Red:Numerical Blue:Analytical a=0.95 = For a << 1 Blandford and Znajek (1997) Monopole solution
Formation of a jet (GRB?) from a Kerr BH Beta_min=100 N×N=150×150 a=0.938, with-magnetic field T=1200 R<60 We are planning to include microphysics and perform more realistic simulations of GRBs in the near future. R<300 G=c=M=1
My Collaborators on GRBs R. Blandford (KIPAC) F. Iocco (KIPAC) S. Pasquale (FermiLab) K. Murase (Kyoto) J. Aoi (Kyoto) A. Mizuta (Chiba) R. Takahashi (U. of Tokyo) T. Kato (OSAKA) K. Asano (NAOJ) T. Yamasaki (CEA Saclay) S. Mineshige (Kyoto) H. Takami (U. of Tokyo) T. Takiwaki (U. of Tokyo) H. Yoshiguchi (U. of Tokyo) S. Tsubaki (U. of Tokyo) K. Kohri (Lancaster) T. Shimizu (RIKEN) S. Yamada (Waseda) H. Takabe (Osaka) M. Hashimoto (Kyusyu) K. Sato (U. of Tokyo) 科学研究費 若手B (H.19-H.21) 「ガンマ線バーストに於けるハドロン加速及び高エネルギー放射」 代表 長瀧重博 科学研究費 基盤S (H.19-H.23) 「超新星の爆発機構とガンマ線バースト源エンジンの統一的解明」 代表 佐藤勝彦 科学研究費 特定領域 (H.19-H.22) 「ガンマ線バーストで読み解く太古の宇宙 」 代表 河合誠之