Resistive Magnetohydrodynamics of Jet Formation and Magnetically Driven Accretion 

作成者 松元, 亮治
キーワード等 accretion, accretion disks, galaxies: active, galaxies: nuclei, galaxies: jets, MHD
日本十進分類法 (NDC) 440
内容 We carried out 2.5-dimensional resistive magnetohydrodynamic simulations to study theeects of magnetic diusivity on magnetically driven mass accretion and jet formation. Theinitial state is a constant angular-momentum torus threaded by large-scale vertical magneticfields. Since the angular momentum of the torus is extracted due to magnetic braking, the torusmedium falls toward the central region. The infalling matter twists the large-scale magneticfields and drives bipolar jets. We found that (1) when the normalized magnetic diusivity,¯ /(r0VK0), where VK0 is the Keplerian rotation speed at a reference radius r = r0, is small(¯ 10-3), mass accretion and jet formation take place intermittently; (2) when 10-3 ¯ 10-2, the system evolves toward a quasi-steady state; and (3) when ¯ 10-2 the accretion/massoutflow rate decreases with ¯ and approaches 0. The results of these simulations indicate thatin the center of a galaxy which has a super-massive ( 109 M) black hole, a massive ( 108M) gas torus and magnetic braking provide a mass accretion rate which is sucient to explainthe activity of AGNs when ¯ 5 × 10-2.
作成日付 2000-11
コンテンツの種類 プレプリント Preprint
DCMI資源タイプ text
ファイル形式 applicaiton/pdf
言語 英語

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