A Study of Rare Earth Elements in the Atmospheres of Chemically Peculiar Stars. Pr III and Nd III Lines

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

31

Scientific paper

We determine the abundances of Pr and Nd in the atmospheres of magnetic and non-magnetic chemically peculiar stars from the lines of rare earth elements in the first and second ionization states. The computations for the magnetic stars take into account the influence of the magnetic field on line formation. We studied the influence of errors in the stellar-atmosphere parameters and the atomic parameters of the spectral lines on the accuracy of abundance determinations. Within the derived accuracy, ionization equilibrium is satisfied in the atmospheres of non-pulsating magnetic and non-magnetic stars (so that abundances derived separately from lines of first and second ions agree). For all the pulsating magnetic (roAp) stars studied, the abundances derived from lines of second ions are 1.0 to 1.7 dex higher than those derived from first ions. The violation of ionization equilibrium in the atmospheres of pulsating stars is probably due to, first, considerable enrichment of Pr and Nd in the uppermost atmospheric layers, and second, a higher location for the layer of enhanced elemental abundance in roAp stars than in non-pulsating stars. Two objects from the list of non-pulsating magnetic stars, HD 62140 and HD 115708, exhibit anomalies of their Pr and Nd lines characteristic of roAp stars. The differences in the rare earth anomalies for the pulsating and non-pulsating peculiar stars can be used as a selection criterion for candidate roAp stars.

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

A Study of Rare Earth Elements in the Atmospheres of Chemically Peculiar Stars. Pr III and Nd III Lines 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 A Study of Rare Earth Elements in the Atmospheres of Chemically Peculiar Stars. Pr III and Nd III Lines, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A Study of Rare Earth Elements in the Atmospheres of Chemically Peculiar Stars. Pr III and Nd III Lines will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-924836

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