Hostname: page-component-76fb5796d-22dnz Total loading time: 0 Render date: 2024-04-27T04:29:06.024Z Has data issue: false hasContentIssue false

Determining The Metallicity of Cepheid Stars in The SMC, LMC and The Galaxy

Published online by Cambridge University Press:  12 April 2016

Marta Mottini
Affiliation:
European Southern Observatory, K. Schwarzschildstrasse 2, D-85748 Garching b. München, Germany
Francesca Primas
Affiliation:
European Southern Observatory, K. Schwarzschildstrasse 2, D-85748 Garching b. München, Germany
Martino Romaniello
Affiliation:
European Southern Observatory, K. Schwarzschildstrasse 2, D-85748 Garching b. München, Germany
Martin Groenewegen
Affiliation:
Instituut voor Sterrenkunde, celestijnenlaan 200B, B-3001 Leuven, Belgium

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

The Cepheid Period-Luminosity relation is unquestionably one of the most powerful tools at our disposal for determining the extragalactic distance scale. While significant progress has been made in the past few years towards its understanding and characterisation, both on the observational (e.g. the HST Key Project) and theoretical (e.g. non-linear pulsation models, non-LTE atmospheres etc.) sides, the debate on the influence that chemical composition may have on the Period-Luminosity relation is still unsettled. Current estimates lead to differences in the distance as large as 15%, effectively limiting the accuracy of Cepheids as distance indicators. To further tackle this problem, we have obtained high resolution spectra of a large sample of Cepheids in our Galaxy and the Magellanic Clouds. The superb quality of the data allow us to probe the detailed effects of chemical composition (alpha, iron-group, and heavy elements) over more than a factor of ten in metallicity. Here, we present the first preliminary results of the analysis of iron abundances in a sub-sample of Cepheids.

Type
Part 7. Chemical composition of variable stars
Copyright
Copyright © Astronomical Society of the Pacific 2004

References

Alibert, Y., Baraffe, I. Hautschildt, P., Allard, F. 1999 A&A, 344, 551 Google Scholar
Andrievsky, S.M., Bersier, D., Kovtyukh, V.V., Luck, R.E., Maciel, W.J., Lépine, J.R.D., Beletsky, Yu.V. 2002a A&A, 384, 140 Google Scholar
Andrievsky, S.M., Kovtyukh, V.V., Luck, R.E., Lépine, J.R.D., Maciel, W.J., Beletsky, Yu.V. 2002b A&A, 392, 491 Google Scholar
Baraffe, L. Alibert, Y. 2001 A&A, 371, 592 Google Scholar
Beaulieu, J.P., Sasselov, D.D., Renault, C. Grison, P., Ferlet, R. et al. 1997 A&A, 318, L47 Google Scholar
Berdnikov, L.N., Caldwell, J.A.R. 2001 JAD, 7, 3 Google Scholar
Bono, G., Caputo, F., Castellani, V., Marconi, M. 1999 ApJ, 512, 711 Google Scholar
Caputo, F., Marconi, M., Musella, I. 2000 A&A, 354, 610 Google Scholar
Fiorentino, G., Caputo, F., Marconi, M., Musella, I. 2002 ApJ, 576, 402 Google Scholar
Fry, A.M., Carney, B.W. 1997 AJ, 113, 1073 Google Scholar
Groenewegen, M.A.T. 1999 A&ASS, 139, 245 Google Scholar
Groenewegen, M.A.T., Oudmaijer, R.D. 2000 A&A, 356, 849 Google Scholar
Kennicutt, R.C., Stetson, P.B., Saha, A., Kelson, D., Rawson, D.M., et al. 1998 ApJ, 498, 181 Google Scholar
Kupka, F., Piskunov, N.E., Ryabchikova, T.A., Stempels, H.C., Weiss, W.W. 1999 A&AS, 138, 119 Google Scholar
Kurucz, R.L. 1993 CD-ROMs #1, 13, 18 Google Scholar
Laney, CD., Stobie, R.S. 1992 A&ASS, 93, 93 Google Scholar
Laney, CD., Stobie, R.S. 1994 MNRAS, 266, 441 Google Scholar
Luck, R.E., Gieren, W.P., Andrievsky, S.M., Kovtyukh, Fouqeé P., Pont, F., Kienzle, F. 2003 A&A, 401, 939 Google Scholar
Macri, L.M., Bothun, G.D., Freedman, W.L., Garnavich, P.M., Jha, S., Madore, B.F., Richmond, M.W. 2001 ApJ, 559, 243 Google Scholar
Piskunov, N.E., Kupka, F., Ryabchikova, T.A., Weiss, W.W., Jeffrey, C.S. 1995 A&AS, 112, 525 Google Scholar
Sandage, A., Bell, R.A., Tripicco, M.J. 1999 ApJ, 522, 250 Google Scholar
Sasselov, D.D., Beaulieu, J.P., Renault, C. Grison, P., Ferlet, R. et al. 1997 A&A, 324, 471 Google Scholar