Quasi-stars, giants and the Schönberg-Chandrasekhar limit

Details Quasi-stars, giants and the Schönberg-Chandrasekhar limit Quasi-stars, giants and the Schönberg-Chandrasekhar limit

2012-01-26

arxiv.org/abs/1201.5560v2

Astronomy and Astrophysics

Astrophysics

Solar and Stellar Astrophysics

9 pages, 7 figures, published in MNRAS. Updated to (more closely) match published version

Scientific paper

The Sch\"onberg-Chandrasekhar (SC) limit is a well-established result in the understanding of stellar evolution. It provides an estimate of the point at which an evolved isothermal core embedded in an extended envelope begins to contract. We investigate contours of constant fractional mass in terms of homology invariant variables U and V and find that the SC limit exists because the isothermal core solution does not intersect all the contours for an envelope with polytropic index 3. We find that this analysis also applies to similar limits in the literature including the inner mass limit for polytropic models of quasi-stars. Consequently, any core solution that does not intersect all the fractional mass contours exhibits an associated limit and we identify several relevant cases where this is so. We show that a composite polytrope is at a fractional core mass limit when its core solution touches but does not cross the contour of the corresponding fractional core mass. We apply this test to realistic models of helium stars and find that stars typically expand when their cores are near a mass limit. Furthermore, it appears that stars that evolve into giants have always first exceeded an SC-like limit.

Affiliated with

Also associated with

No associations

Rating

Quasi-stars, giants and the Schönberg-Chandrasekhar limit 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 Quasi-stars, giants and the Schönberg-Chandrasekhar limit, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Quasi-stars, giants and the Schönberg-Chandrasekhar limit will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-445863