Chemical Evolution of Mg Isotopes versus the Time Variation of the Fine Structure Constant
Abstract
We show that the synthesis of 25,26Mg at the base of the convective envelope in low-metallicity asymptotic giant branch stars can produce the isotopic ratios needed to explain the low-z subset (with z<1.8) of the many-multiplet data from quasar absorption systems without invoking a time variation of the fine structure constant. This is supported by observations of high abundances of the neutron-rich Mg isotopes in metal-poor globular-cluster stars. We conclude that the quasar absorption spectra may be providing interesting information on the nucleosynthetic history of such systems.
- Publication:
-
Physical Review Letters
- Pub Date:
- January 2004
- DOI:
- 10.1103/PhysRevLett.92.041102
- arXiv:
- arXiv:astro-ph/0309197
- Bibcode:
- 2004PhRvL..92d1102A
- Keywords:
-
- 98.62.Bj;
- 06.20.Jr;
- 97.10.Cv;
- 98.80.Es;
- Chemical composition and chemical evolution;
- Determination of fundamental constants;
- Stellar structure interiors evolution nucleosynthesis ages;
- Observational cosmology;
- Astrophysics;
- High Energy Physics - Phenomenology
- E-Print:
- 4 pages, latex, 1 eps figure