Discrete High-Frequency p-Modes
Abstract
Observations report that the p-mode frequencies change with the solar activity cycle. Over the frequency range 0 to 8.5 mHz, shifts can be either positive or negative, appearing to exhibit a wavelike behavior with downturn occurring at ∼4.0 mHz and upturn at ∼5.5 mHz. A simple polytrope convection zone model overlaid with an isothermal chromospheric atmosphere threaded by a uniform horizontal magnetic field demonstrates frequency shifts that are qualitatively similar to those observed for both high and low frequencies, with shifts being a consequence of simultaneous increases in chromospheric field strength and temperature.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- January 1996
- DOI:
- 10.1086/176662
- Bibcode:
- 1996ApJ...456..399J
- Keywords:
-
- SUN: ACTIVITY;
- SUN: MAGNETIC FIELDS;
- SUN: OSCILLATIONS