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Stellar model chromospheres. IX - Chromospheric activity in dwarf starsHigh-resolution Ca II K line profiles are used to model the upper photospheres and lower chromospheres of eight main-sequence stars ranging in spectral type from F0 to M0 and exhibiting different degrees of chromospheric activity. The model chromospheres are studied as a function of spectral type and activity for stars of similar spectral type in order to obtain evidence of enhanced nonradiative heating in the upper-photospheric models and in the ratio of minimum temperature at the base of the chromosphere to effective temperature, a correlation between activity and temperature in the lower chromospheres, and a correlation of the width at the base of the K-line emission core and at the K2 features with activity. Chromospheric radiative losses are estimated for the modelled stars and other previously analyzed main-sequence stars. The results obtained strengthen the argument that dMe flare stars exhibit fundamentally solar-type activity but on an increased scale.
Document ID
19790049143
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Kelch, W. L. (Joint Institute for Laboratory Astrophysics Boulder, Colo., United States)
Worden, S. P. (Sacramento Peak Observatory Sunspot, N. Mex., United States)
Linsky, J. L. (Joint Inst. for Lab. Astrophysics Boulder, CO, United States)
Date Acquired
September 3, 2013
Publication Date
April 15, 1979
Publication Information
Publication: Astrophysical Journal
Subject Category
ASTROPHYSICS
Report/Patent Number
AD-A083858
AFGL-TR-80-0106
PB80-118086
Funding Number(s)
CONTRACT_GRANT: NGL-06-003-057
CONTRACT_GRANT: NAS5-23274
Distribution Limits
Public
Copyright
Other