Slow Magnetoacoustic Oscillations in Stellar Coronal Loops

Abstract

Slow magnetoacoustic oscillations in stellar coronal loops with gravitational stratification are analyzed with a numerical solution of the boundary-value problem for eigenvalues and eigen functions. In this study, we only focus on the resonant periods. The effects of the gravitational stratification, star mass, loop temperature, and loop length on the properties of slow magnetoacoustic oscillations are investigated. It is shown that the discrepancy between stratified and non-stratified loops is higher in density perturbations than velocity perturbations. When the star has larger mass, higher coronal temperature, and longer loop, the density perturbations in stratified loop are significantly different from the harmonic functions. The periods in the stratified loop are slightly longer than in the non-stratified loop. The periods calculated in our model (14-644 min) are consistent with the periods of stellar quasi-periodic pulsations observed in both soft x-rays (2-70 min) and white lights (8-390 min).

14 pages, 6 figures, accepted for publication in ApJ

References in corpus (7)

• The Helium abundance and Delta Y / Delta Z in Lower Main Sequence stars
• The first observed stellar X-ray flare oscillation: Constraints on the flare loop length and the magnetic field
• GALEX high time-resolution ultraviolet observations of dMe flare events
• SDO/AIA Observations of a Reflecting Longitudinal Wave in a Coronal Loop
• Oscillations in stellar superflares
• Observations of Solar Doppler Shift Oscillations with the EUV Imaging Spectrometer on Hinode
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Cited by in corpus (2)

• Coronal seismology by slow waves in non-adiabatic conditions
• Impact of thermal misbalance on acoustic-gravity waves in the solar atmosphere