论文标题
等离子体驱动的超级不稳定性的数值调查
Numerical investigation of plasma-driven superradiant instabilities
论文作者
论文摘要
在等离子体中传播的光子获得有效的质量$ $ $，该$ $ $由等离子体频率给出，并以等离子体密度的平方根缩放。如Conlon和Herdeiro之前指出的那样，对于电子数密度$ n_e \ sim \ sim 10^{ - 3} $ cm $^{ - 3} $（例如在星际介质中测量的），由等离子体诱导的有效质量是由等离子体引起的$μ\ sim \ sim 10^{ - 12} $ ev。这将导致超级不稳定性旋转几十个太阳能的黑洞。这张照片的一个明显问题是，黑洞附近的密度远高于由于积聚而高得多的星际介质。我们已经对超级不稳定性进行了数值模拟，以旋转黑色孔，该黑洞被血浆包围，密度越来越靠近黑洞，以模仿积聚的效果。虽然我们确认在黑洞附近足够低的等离子密度出现了超级不稳定性，但我们发现天体现实的积聚磁盘不太可能触发这种不稳定性。
Photons propagating in a plasma acquire an effective mass $μ$, which is given by the plasma frequency and which scales with the square root of the plasma density. As noted previously by Conlon and Herdeiro, for electron number densities $n_e\sim 10^{-3}$ cm$^{-3}$ (such as those measured in the interstellar medium) the effective mass induced by the plasma is $μ\sim 10^{-12}$ eV. This would cause superradiant instabilities for spinning black holes of a few tens of solar masses. An obvious problem with this picture is that densities in the vicinity of black holes are much higher than in the interstellar medium because of accretion. We have conducted numerical simulations of the superradiant instability in spinning black holes surrounded by a plasma with density increasing closer to the black hole, in order to mimic the effect of accretion. While we confirm that superradiant instabilities appear for plasma densities that are sufficiently low near the black hole, we find that astrophysically realistic accretion disks are unlikely to trigger such instabilities.
