Astronomy and Astrophysics – Astronomy
Scientific paper
May 1993
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1993aas...182.4609v&link_type=abstract
American Astronomical Society, 182nd AAS Meeting, #46.09; Bulletin of the American Astronomical Society, Vol. 25, p.875
Astronomy and Astrophysics
Astronomy
Scientific paper
We present outstanding infrared spectra of the active star epsilon Eridani (K2V) and two inactive reference stars, 40 Eridani (K1V) and sigma Draconis (K0V). The spectra are the result of 9 hours of observations per star with the IR FTS at the 4--m Mayall Telescope at Kitt Peak National Observatory. The noise is 0.5--1.0% with an unapodized spectral resolution of 120,000. The wavelength range covered is 1.54-1.59 microns (6290--6490 cm(-1) ) in air, which includes two dozen moderate strength lines, notably the Lande--g=3 line at 1.5649 microns. This line is a superior magnetic diagnostic because of its high Lande--g factor, long wavelength, and large depth of formation. The Zeeman sensitivity of this line is at least a factor of 2--3 times greater than any optical line. We employ a polarized radiative tranfer code to simultaneously model the profiles of clean neutral iron lines in our infrared spectra and high quality optical spectra. The inactive stars are used to determine and check oscillator strengths and to assess the accuracy of our models. We then model epsilon Eridani both with and without a magnetic field. The observed wings of the magnetically sensitive 1.5649 microns line are clearly deeper than predicted by the B=0 model. No such discrepency is observed in the insensitive lines or in inactive stars. We then fit the epsilon Eridani profiles with various magnetic models. A model with depth independent magnetic fields yields a (preliminary) field strength of 1.9 kG covering 12% of the stellar surface. We also consider the observable effects of magnetic fields that vary with depth or across the stellar surface.
Basri Gibor
Marcy Geoffrey W.
Valenti Jeff A.
No associations
LandOfFree
Magnetic Fields on epsilon Eridani from High Quality FTS Spectra near 1.6 microns 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 Magnetic Fields on epsilon Eridani from High Quality FTS Spectra near 1.6 microns, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Magnetic Fields on epsilon Eridani from High Quality FTS Spectra near 1.6 microns will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1849382