TY - JOUR
T1 - The electron pressure in the outer atmosphere of ∈ Eri (K2 V)
AU - Jordan, C.
AU - Sim, S.A.
AU - McMurry, A.D.
AU - Aruvel, M.
N1 - Copyright 2005 Elsevier Science B.V., Amsterdam. All rights reserved.
PY - 2001/9/1
Y1 - 2001/9/1
N2 - Observations of ? Eri (K2 V) have been made with the Space Telescope Imaging Spectrograph on the Hubble Space Telescope. The spectra obtained show a number of emission lines which can be used to determine, or place limits on, the electron density and pressure. Values of the electron pressure are required in order to make quantitative models of the transition region and inner corona from absolute line fluxes, and to constrain semi-empirical models of the chromosphere. Using line flux ratios in Si II and O IV a mean electron pressure of P = NT = 4.8 × 10 cm K is derived. This value is compatible with the lower and upper limits to P found from flux ratios in C III, O V and Fe XII. Some inconsistencies which may be because of small uncertainties in the atomic data used are discussed.
AB - Observations of ? Eri (K2 V) have been made with the Space Telescope Imaging Spectrograph on the Hubble Space Telescope. The spectra obtained show a number of emission lines which can be used to determine, or place limits on, the electron density and pressure. Values of the electron pressure are required in order to make quantitative models of the transition region and inner corona from absolute line fluxes, and to constrain semi-empirical models of the chromosphere. Using line flux ratios in Si II and O IV a mean electron pressure of P = NT = 4.8 × 10 cm K is derived. This value is compatible with the lower and upper limits to P found from flux ratios in C III, O V and Fe XII. Some inconsistencies which may be because of small uncertainties in the atomic data used are discussed.
UR - http://www.scopus.com/inward/record.url?partnerID=yv4JPVwI&eid=2-s2.0-0043094526&md5=9ae10cfdbc5c9e515f5000f07cf14a0d
U2 - 10.1046/j.1365-8711.2001.04599.x
DO - 10.1046/j.1365-8711.2001.04599.x
M3 - Article
AN - SCOPUS:0043094526
VL - 326
SP - 303
EP - 312
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
SN - 0035-8711
IS - 1
ER -