Lithium abundances and metallicities in stars near the main-sequence turnoff and a giant in M67

Garcia Lopez, R. J.; Rebolo, R.; Beckman, J. E.
Referencia bibliográfica

Astronomical Society of the Pacific, Publications (ISSN 0004-6280), vol. 100, Dec. 1988, p. 1489-1496. Research supported by Instituto de Astrofisica de Canarias.

Fecha de publicación:
12
1988
Número de autores
3
Número de autores del IAC
3
Número de citas
76
Número de citas referidas
65
Descripción
The iron abundance of seven stars near the main-sequence (MS) turnoff and a giant in M67 are spectroscopically derived, and the results are discussed. The resulting mean iron abundance of the turnoff stars is (Fe/H) = 0.04 + or - 0.04. Taken together with previous determinations for younger clusters, this shows that there has been relatively little change of the iron abundance in the solar neighborhood during the last 5 Gyr. Lithium was detected in one unevolved star and marginally in the giant, while in the other MS stars only upper limits were found. The considerable differences in Li abundances for stars with similar surface temperature imply that there is at least one parameter affecting Li depletion apart from stellar mass and metallicity. Nonsimultaneous star formation in the cluster cloud explain the scatter in lithium abundances.