2018/01/28 by Shaoxia Chen, Shao-Xia Chen, Bo Li +3
Physics and Astronomy · #BETA (programming language) #Classical mechanics #Computational physics #Condensed matter physics #Coronal loop #Coronal mass ejection #Coronal plane #Dispersion relation #Ionosphere and magnetosphere dynamics #Magnetohydrodynamics #Mechanics #Optics #Physics #Plasma #Quantum mechanics #Solar and Space Plasma Dynamics #Solar wind #Stellar, planetary, and galactic studies #Transverse plane #Transverse wave #Wave propagation #Wavenumber #astro-ph.SR
paper · pdf · doi:10.3847/1538-4357/aaab5d
8 figures, accepted for publication in ApJ
arxiv created 2018/01/28 · openalex created_date 2018/02/23 · openalex publication_date 2018/03/01 · arxiv updated 2018/03/21 · openalex updated_date 2026/08/05
Abstract We examine the dispersive properties of linear fast standing modes in transversely nonuniform solar coronal slabs with finite gas pressure, or, equivalently, finite plasma beta. We derive a generic dispersion relation governing fast waves in coronal slabs, for which the continuous transverse distributions of the physical parameters comprise a uniform core, a uniform external medium, and a transition layer (TL) in between. The profiles in the TL are allowed to be essentially arbitrary. Restricting ourselves to the first several branches of fast modes, which are mostly interesting from an observational standpoint, we find that a finite plasma beta plays an at most marginal role in influencing the periods ( P ), damping times ( τ ), and critical longitudinal wavenumbers ( ), when both P and τ are measured in units of the transverse fast time. However, these parameters are in general significantly affected by how the TL profiles are described. We conclude that, for typical coronal structures, the dispersive properties of the first several branches of fast standing modes can be evaluated with the much simpler theory for cold slabs, provided that the transverse profiles are properly addressed and the transverse Alfvén time in cold MHD is replaced with the transverse fast time.