Astronomy and Astrophysics – Astronomy
Scientific paper
Jan 2004
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2004iaus..219..254s&link_type=abstract
Stars as suns : activity, evolution and planets, Proceedings of the 219th symposium of the International Astronomical Union held
Astronomy and Astrophysics
Astronomy
Scientific paper
Analyses of the fluxes widths and shifts of lines in the ultraviolet spectrum of the active dwarf Epsilon Eri (K2 V) are presented. The spectra were recorded with the STIS and FUSE instruments and provide detailed new information on the star's chromosphere transition region and inner corona. A combination of simple theoretical arguments and observational constraints are used to deduce new information about the structure of the upper transition region/corona. The area filling factor of emitting material is determined in the upper atmosphere as a function of temperature. This provides new constraints on how the magnetic field might expand between the transition region and corona of an active main sequence star. The results are compared with similar studies of the Sun. The line widths are used together with a new semi-empirical model of the atmosphere to compute the non-thermal energy density as a function of temperature. Limits on the energy fluxes carried by acoustic and Alfven waves are derived and compared with estimates of the energy input required to support the combined radiative/conductive losses in the upper atmosphere. It is found that in principle Alfven waves could provide sufficient energy to heat the corona.
Jordan Cathy
Sim Stuart A.
No associations
LandOfFree
The Structure and Dynamics of the Outer Atmosphere of &epsil Eri does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with The Structure and Dynamics of the Outer Atmosphere of &epsil Eri, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Structure and Dynamics of the Outer Atmosphere of &epsil Eri will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1545272