The carbon Cepheid V553 Cen: evidence of triple-alpha and CNO cycling

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

13

Stars: Abundances, Stars: Chemically Peculiar, Stars: Individual: V553 Cen, Stars: Population Ii, Cepheids

Scientific paper

We have obtained high-resolution spectroscopic observations of V553 Cen, a short-period type II Cepheid. We have confirmed the findings of previous investigators that V553 Cen is C- and N-rich. For the first time, we show that V553 Cen is also O-poor and Na-rich, and that ^12C/^13C=4+/-1. We do not see s-process element enhancements in this star. When compared to historical observations, our radial velocity measurements indicate that V553 Cen does not have a binary companion. Hence the abundance peculiarities we observe on the surface are due to V553 Cen altering its own composition by nuclear reaction sequences and dredge-up episodes. These results imply that V553 Cen has experienced CN, ON and triple-alpha processing, and has mixed the products of these reactions to its surface. The chemical composition of V553 Cen and the kinematics of the carbon Cepheids indicate that they are of the same population as early R stars. The evolutionary processes that have produced such objects are not known, but are suspected to be due to helium core flashing in low-mass stars of normal metallicity, as suggested by both Lloyd Evans and Dominy.

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

The carbon Cepheid V553 Cen: evidence of triple-alpha and CNO cycling 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 carbon Cepheid V553 Cen: evidence of triple-alpha and CNO cycling, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The carbon Cepheid V553 Cen: evidence of triple-alpha and CNO cycling will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1137660

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