Oscillations of Innermost Region of Relativistic Accretion Disks

相对论吸积盘最内部区域的振荡

• 批准号: 63460010
• 负责人: KATO Shoji
• 金额: $ 3.33万
• 依托单位: KYOTO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1988
• 资助国家: 日本
• 起止时间: 1988 至 1989
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-63460010/
• 关键词: Relativistic Accretion; Oscillatory Phenomena; Instability; Quasi-Periodic Oscillations(QPO); 遷音点; 振動; エピサイクリック振動数; コルゲイション波

Roughly speaking, we had two major results. The first is that (1)the innermost part of relativistic accretion disks is pulsationally unstable, when the so-called alpha-parameter of viscosity is larger than a critical value. The second is that(2) one-armed corrugation waves in the innermost part of relativistic accretion disks are low frequency oscillations whose frequencies are comparable with those of quasi-periodic oscillations (QPO's) observed in low mass X-ray binaries.(1)The innermost part of relativistic accretion disks has the sonic point where the accretion flow becomes supersonic. We found analytically that the sonic point region is pulsationally unstable when viscosity is large. Subsequently this was confirmed by numerical simulations. Numerical simulations show further that the oscillations have long term variations. This modulation period was found to be comparable with that of QPO'S.(2)As an oscillations mode whose frequency is as low as that of QPO's, we found one-armed corrugation waves. Corrugation waves are wavy oscillations of disks in the direction perpendicular to the disk plane. We found further that under some circumstances there corrugation waves can be trapped in the innermost part of relativistic accretion disks. This will be in favor of explaining QPO'S.

大致说来，我们有两个主要结果。第一个结论是：（1）当粘性α参数大于某个临界值时，相对论吸积盘的最内层是脉动不稳定的。（2）在相对论吸积盘最内部的单臂振荡是低频振荡，其频率与低质量X射线双星中的准周期振荡（QPO）相当。（1）相对论吸积盘的最里面部分具有音速点，在该音速点处吸积流变为超音速。我们分析发现，音速点区域是脉动不稳定的粘度大时。随后通过数值模拟证实了这一点。数值模拟进一步表明，振荡具有长期变化。发现该调制周期与QPO的调制周期相当。(2)As一种频率与QPO一样低的振荡模式，我们发现了单臂的行波。波纹波是圆盘在垂直于圆盘平面的方向上的波动。我们进一步发现，在某些情况下，在相对论吸积盘的最里面可以捕获到光波。这将有助于解释QPO。

项目成果

Shoji Kato: "Trapped Oscillations in the Region Around max." Proceedings of the YAMADA Conference XX on Big Bang,Active Galactic Nuclei and Supernovae.(Universal Academy Press,Inc.). 373-374 (1989)

Shoji Kato：“最大区域内的陷波振荡”

Abramowicz, M.A., Kato, S., and Matsumoto, R.: "Numerical Models of Slim Accretion Disks," Publ.Astron. Soc.Japan, Vol.41, 1215-1218, 1989.

Abramowicz, M.A.、Kato, S. 和 Matsumoto, R.：“细长吸积盘的数值模型”，Publ.Astron。

S.Kato: Proceeding of the YAMADA Conference XX on Big Bang,Active Galactic Nuclei and Supernovae.20. 373-374 (1988)

S.Kato：YAMADA Conference XX 关于大爆炸、活动星系核和超新星的会议记录。20。

Marek A.Abramowicz: "Numerical Models of Slim Accretion Disks." Publ.Astron.Soc.Japan(印刷中). 41. (1989)

Marek A.Abramowicz：“细长吸积盘的数值模型。”Publ.Astron.Soc.Japan（出版中）41。（1989）。

Marek A.Abramowicz: "Numerical Models of Slim Accretion Disks." Publ.Astron.Soc.Japan. 41. (1989)

Marek A.Abramowicz：“细长吸积盘的数值模型。”