Influence of two updated nuclear reaction rates on the evolution of low and intermediate mass stars

¹ Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, 85748 Garching, Germany e-mail: weiss@mpa-garching.mpg.de
² Institute for Advanced Study, Einstein Drive, Princeton NJ 08540, USA
³ Institut for Fysik og Astronomi, Aarhus Universitet, Bygn. 520, Ny Munkegade, 8000 Aarhus C, Denmark

Received: 18 March 2005
Accepted: 19 July 2005

Abstract

Two key reactions of hydrostatic nuclear burning in stars have recently been revised by new experimental data – the and reaction rates. We investigate how much the new rates influence the evolution of low-mass, metal-poor and metal-free stars and of an intermediate-mass star of solar-type composition. We concentrate on phases of helium ignition or thermally unstable helium burning. Our global result is that the new rate has no significant influence on such stars, but that there is a noticeable though small effect of the new rate, in particular on the core helium flash and the blue loop during core helium burning in the intermediate-mass star.