期刊
ASTROPHYSICAL JOURNAL
卷 874, 期 1, 页码 -出版社
IOP PUBLISHING LTD
DOI: 10.3847/1538-4357/ab09ec
关键词
hydrodynamics; methods: analytical; shock waves; supernovae: general
资金
- NASA [PF6-170170]
- Simons Investigator award from the Simons Foundation
- Gordon and Betty Moore Foundation [GBMF5076]
Coughlin et al. derived and analyzed a new regime of self-similarity that describes weak shocks (Mach number of order unity) in the gravitational field of a point mass. These solutions are relevant to low-energy explosions, including failed supernovae. In this paper, we develop a formalism for analyzing the stability of shocks to radial perturbations, and we demonstrate that the self-similar solutions of Paper I are extremely weakly unstable to such radial perturbations. Specifically, we show that perturbations to the shock velocity and post-shock fluid quantities (the velocity, density, and pressure) grow with time as t(alpha); interestingly, we find that alpha less than or similar to 0.12, implying that the 10-folding timescale of such perturbations is roughly 10 orders of magnitude in time. We confirm these predictions by performing high-resolution, time-dependent numerical simulations. Using the same formalism, we also show that the Sedov-Taylor blast wave is trivially stable to radial perturbations provided that the self-similar, Sedov-Taylor solutions extend to the origin, and we derive simple expressions for the perturbations to the post-shock velocity, density, and pressure. Finally, we show that there is a third, self-similar solution (in addition to the solutions in Paper I and the Sedov-Taylor solution) to the fluid equations that describes a rarefaction wave, i.e., an outward-propagating sound wave. We interpret the stability of shock propagation in light of these three distinct self-similar solutions.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据