The Extreme-Ultraviolet Spectrum of the Nearby K Dwarf epsilon Eridani

Abstract

view Abstract Citations (37) References (26) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The Extreme-Ultraviolet Spectrum of the Nearby K Dwarf ɛ Eridani Schmitt, J. H. M. M. ; Drake, J. J. ; Stern, R. A. ; Haisch, B. M. Abstract We present and discuss the extreme-ultraviolet spectrum of the nearby K2 dwarf ɛ Eri obtained with the spectrometers onboard the Extreme-Ultraviolet Explorer satellite (EUVE). In the EUVE spectrum of ɛ Eri we detect emission lines attributable to iron in the ionization stages Fe IX to Fe XXI, thus covering a rather large temperature range from less than 106 K to 107 K. While the lines in the lowest and highest ionization stages are relatively weak, the strongest lines detected are from Fe XV and Fe XVI, from which we infer a peak in the differential emission measure distribution at coronal temperatures of log Tc ∼ 6.4; significant emission measure is, however, also present at both higher and lower temperatures. This is in contrast to both lower activity stars whose EUV spectra are dominated by cooler Fe lines in the range 170-180 Å as well as the more active stars whose EUV spectra are dominated by hotter Fe lines in the range 110-135 Å. Finally, a density determination using line ratios of Fe XIII and Fe XIV results in coronal densities for ɛ Eri which are similar to solar active region densities. Publication: The Astrophysical Journal Pub Date: February 1996 DOI: 10.1086/176783 Bibcode: 1996ApJ...457..882S Keywords: STARS: CORONAE; STARS: INDIVIDUAL CONSTELLATION NAME: EPSILON ERIDANI; STARS: LATE-TYPE; ULTRAVIOLET: STARS full text sources ADS | data products SIMBAD (7) MAST (2) HEASARC (1)