2018/03/05 by Asiyeh Yaghoobi, Mohsen Shadmehri
Physics and Astronomy · #Astro and Planetary Science #Astrophysics #Astrophysics and Star Formation Studies #Computational physics #Growth rate #Instability #Magnetic field #Mechanics #Optics #Physics #Radiative transfer #Rayleigh–Taylor instability #Stellar, planetary, and galactic studies #Wavelength #astro-ph.GA
paper · pdf · doi:10.1093/mnras/sty623
10 pages, 6 figures, Accepted for publication in MNRAS
arxiv created 2018/03/05 · openalex publication_date 2018/03/07 · arxiv updated 2018/03/28 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We present a linear analysis of the radiative Rayleigh–Taylor (RT) instability in the presence of magnetic field for both optically thin and thick regimes. When the flow is optically thin, magnetic field not only stabilizes perturbations with short wavelengths, but also growth rate of the instability at long wavelengths is reduced compared to a non-magnetized case. Then, we extend our analysis to the optically thick flows with a conserved total specific entropy, and properties of the unstable perturbations are investigated in detail. Growth rate of the instability at short wavelengths is suppressed due to the presence of the magnetic field; however, growth rate is nearly constant at long wavelengths because of the radiation field. Since the radiative bubbles around massive protostars are subject to the RT instability, we also explore implications of our results in this context. In the non-magnetized case, the growth time-scale of the instability for a typical bubble is found to be less than 1000 yr, which is very short compared to the typical star formation time-scale. Magnetic field with a reasonable strength significantly increases the growth time-scale to more than hundreds of thousand years. The instability, furthermore, is more efficient at large wavelengths, whereas in the non-magnetized case, growth rate at short wavelengths is more significant.