Height and dynamics of the quiet solar chromosphere at the limb

Citation
K. Muglach et W. Schmidt, Height and dynamics of the quiet solar chromosphere at the limb, ASTRON ASTR, 379(2), 2001, pp. 592-600
Citations number
43
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Space Sciences
Journal title
ASTRONOMY & ASTROPHYSICS
ISSN journal
1432-0746 → ACNP
Volume
379
Issue
2
Year of publication
2001
Pages
592 - 600
Database
ISI
SICI code
1432-0746(200111)379:2<592:HADOTQ>2.0.ZU;2-K
Abstract
In this paper we present observations of He I 1083.0 nm, He D-3 587.6 nm an d H beta 486.1 nm taken at various positions at the solar limb. We determin e and compare the emission of the lines in terms of line-parameters. The he ight of the chromosphere as seen in the helium lines varies in space and ti me and reaches values between 1100 and 1800 km above the continuum and is t he same for both helium lines within the errors of the measurement. From a time-sequence of slit-spectra of about 23 min we study the oscillation sign ature of the chromosphere near the solar limb. We find velocity oscillation s in He I 1083.0 nm that do not drop to zero near the limb as would be expe cted of vertically oriented oscillations, we even get horizontal oscillatio ns in the off-limb emission data of both helium lines.