Relation between the mode of oscillation and the velocity amplitude of chromospheric waves

✍ Scribed by N. Mein

• Publisher: Springer
• Year: 1978
• Tongue: English
• Weight: 297 KB
• Volume: 59
• Category: Article
• ISSN: 0038-0938
• DOI: 10.1007/bf00154926

✦ Synopsis

The distribution of oscillation-amplitude for Doppler shifts in chromospheric lines is computed as a function of position on the disk and time frequency. High amplitude regions are restricted to a small part of the solar surface. Propagation modes are investigated with respect to the oscillation amplitude in the K line. Waves seem to be standing or evanescent for most of the points (small amplitude in K) and progressive for some other ones, with perhaps upward and downward motions (partial reflections). Mechanical energy could only escape into corona from narrow chromospheric structures.

In this work we are interested in the spatial distribution of chromospheric oscillations. We analyse the distribution of oscillatory power along a straight line on the disk, for different spectral lines and for different time frequencies. We determine a relationship between the strength of the oscillation and the propagation characteristics of the mode.