Calibrating convection efficiency with quasi-molecular features in magnetic white dwarfs

Statistics – Computation

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Hst Proposal Id #9179 Hot Stars

Scientific paper

We have discovered quasi-molecular absorption features of Lyman Alpha {at 1400 and 1600 Angstrom} in UV spectra of magnetic white dwarfs taken with IUE; hitherto such features have only been known in non-magnetic objects where they offered a very accurate determination of the atmospheric parameters. With high quality HST/STIS UV spectra of five white dwarfs we will for the first time be able to study the molecular potential of H_2 and H_2^+ under the influence of a magnetic field and to compare the results to theoretical calculations. Besides the relevance for atomic and molecular physics, the HST observations will be a tool to precisely determine effective temperatures and gravities {and thereby age and mass}. Even more important is the possibility to test the efficiency of convection under the influence of a strong magnetic field and to find out how strongly the degree of ionization equilibrium is modified by the magnetic field. Convection is a completely free parameter in the computation of the model atmospheres and the analyses of all magnetic white dwarfs with effective temperatures between 10000 K and about 17000 K suffer from this uncertainty. Finally, one of our target stars is within an close binary {AM Her-type}, and provides us with the possibility to test how the quasi- molecular features change due to the enrichment of the hydrogen atmosphere with heavy elements from the secondary star.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Calibrating convection efficiency with quasi-molecular features in magnetic white dwarfs 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 Calibrating convection efficiency with quasi-molecular features in magnetic white dwarfs, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Calibrating convection efficiency with quasi-molecular features in magnetic white dwarfs will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1200637

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.