TY - JOUR
T1 - Modelling the chromosphere and transition region of ε Eri (K2 V)
AU - Sim, S.A.
AU - Jordan, C.
N1 - Copyright 2011 Elsevier B.V., All rights reserved.
PY - 2005/8/11
Y1 - 2005/8/11
N2 - Measurements of ultraviolet line fluxes from Space Telescope Imaging Spectrograph and Far-Ultraviolet Spectroscopic Explorer spectra of the K2-dwarf e Eri are reported. These are used to develop new emission measure distributions and semi-empirical atmospheric models for the chromosphere and lower transition region of the star. These models are the most detailed constructed to date for a main-sequence star other than the Sun. New ionization balance calculations, which account for the effect of finite density on dielectronic recombination rates, are presented for carbon, nitrogen, oxygen and silicon. The results of these calculations are significantly different from the standard Arnaud & Rothenflug ion balance, particularly for alkali-like ions. The new atmospheric models are used to place constraints on possible first ionization potential (FIP)-related abundance variations in the lower atmosphere and to discuss limitations of single-component models for the interpretation of certain optically thick line fluxes.
AB - Measurements of ultraviolet line fluxes from Space Telescope Imaging Spectrograph and Far-Ultraviolet Spectroscopic Explorer spectra of the K2-dwarf e Eri are reported. These are used to develop new emission measure distributions and semi-empirical atmospheric models for the chromosphere and lower transition region of the star. These models are the most detailed constructed to date for a main-sequence star other than the Sun. New ionization balance calculations, which account for the effect of finite density on dielectronic recombination rates, are presented for carbon, nitrogen, oxygen and silicon. The results of these calculations are significantly different from the standard Arnaud & Rothenflug ion balance, particularly for alkali-like ions. The new atmospheric models are used to place constraints on possible first ionization potential (FIP)-related abundance variations in the lower atmosphere and to discuss limitations of single-component models for the interpretation of certain optically thick line fluxes.
UR - http://www.scopus.com/inward/record.url?partnerID=yv4JPVwI&eid=2-s2.0-23844483912&md5=56884d3cd43afbbe00aaa186c28d761f
U2 - 10.1111/j.1365-2966.2005.09247.x
DO - 10.1111/j.1365-2966.2005.09247.x
M3 - Article
AN - SCOPUS:23844483912
VL - 361
SP - 1102
EP - 1120
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
SN - 0035-8711
IS - 3
ER -