AAS 196th Meeting, June 2000
Session 40. High Resolution Spectroscopy at Visible and Ultraviolet Wavelengths
Topical Contributed Display, Wednesday, June 7, 2000, 10:00am-7:00pm, Empire Hall South

[Previous] | [Session 40] | [Next]

[40.11] Analysis of A-F Supergiants in M31 from Keck HIRES Spectroscopy

K.A. Venn (Macalester College), J.K. McCarthy (Caltech), D.J. Lennon (ING, La Palma), N. Pryzbilla, R.P. Kudritzki (USM, Munich), M. Lemke (Bamberg)

The first stellar abundances in M31 are presented, based on Keck I HIRES spectroscopy and model atmospheres analyses of three A-F supergiants, 41-2368, 41-3712, and A-207. We find that the stellar oxygen abundances are in good agreement with those determined from nebular studies, even though the stars do NOT show a clear radial gradient in oxygen. The uncertainties in the stellar abundances are smaller than the range in the nebular results, making these stars ideal objects for further studies of the distribution of oxygen in M31. We show that the stars can be used to study the abundance distributions of other elements as well, including iron-group and heavier elements. The A-F supergiants also provide direct information on the metallicity and reddening of nearby Cepheid stars. We have examined the metallicity and reddening assumptions used for Cepheids within 1' of our targets and noted differences from values used in the literature. This work has recently been submitted to the Astrophysical Journal.

The author(s) of this abstract have provided an email address for comments about the abstract: venn@clare.physics.macalester.edu

[Previous] | [Session 40] | [Next]