EDP Sciences
Free access
Volume 379, Number 3, December I 2001
Page(s) 1106 - 1112
Section The Sun
DOI http://dx.doi.org/10.1051/0004-6361:20011378
A&A 379, 1106-1112 (2001)
DOI: 10.1051/0004-6361:20011378

Wide-spectrum slow magnetoacoustic waves in coronal loops

D. Tsiklauri and V. M. Nakariakov

Physics Department, University of Warwick, Coventry, CV4 7AL, England, UK

(Received 25 July 2001 / Accepted 27 September 2001 )

A model interpreting variations of EUV brightness upward propagating in solar coronal loops as slow magnetoacoustic waves is developed. A loop is considered to have a non-zero plane inclination angle and offset of the circular loop centre from the baseline. The model also incorporates effects of dissipation and gravitational stratification. A linear evolutionary equation is derived and applied to investigations of slow wave dynamics. Both the non-zero plane inclination and the offset decrease the growth of the wave amplitude due to stratification. It is shown that wide-spectrum slow magnetoacoustic waves, consistent with currently available observations in the low frequency part of the spectrum, can provide a rate of heat deposition sufficient to heat the loop. In this scenario, the heat would be deposited near the loop footpoints, which agrees with the current observational data.

Key words: magnetohydrodynamics (MHD) -- waves -- Sun: activity -- Sun: corona -- Sun: oscillations -- Sun: UV radiation

Offprint request: David Tsiklauri, tsikd@astro.warwick.ac.uk

© ESO 2001