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Surface lithium and cool spots

Published online by Cambridge University Press:  25 May 2016

F. C. Fekel
F. C. Fekel*
Affiliation:
Center for Automated Space Science and Center of Excellence in Information Systems Tennessee State University, Nashville, TN 37203, USA

Abstract

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Observations of lithium in sunspots resulted in the prediction of significant lithium equivalent-width variability in chromospherically active stars. Lithium observations of several types of active stars, such as pre-main-sequence stars and late-type dwarfs in very young clusters, whose members are assumed to be nearly coeval, as well as post-main-sequence objects, show a significant range of abundances. Thus, a number of researchers over the past decade have investigated star spots as the possible cause of the various observed lithium-abundance spreads. Observationally, some evidence has been found for lithium equivalent-width variations. Computed synthetic spectra indicate that under certain conditions significant variations should be detected, but such conditions are not often met except perhaps in the most active stars. While variations have been claimed for some T Tauri stars, simultaneous photometry and spectroscopy will be needed to explore the complex relation of spots and lithium-abundance variations. The fact that some post-main-sequence stars have lithium abundances similar to those of pre-main-sequence stars complicates the identification of isolated pre-main-sequence systems.

Type
Session III: “Photospheric Phenomena: Results”
Information
Symposium - International Astronomical Union , Volume 176: Stellar Surface Structure , 1996 , pp. 345 - 351
Copyright
Copyright © Kluwer 1996 

References

Basri, G., Martín, E. L., Bertout, C., 1991, A&A 252, 625 Google Scholar
Boesgaard, A. M., 1991, The Formation and Evolution of Star Clusters , ASP Conf. Series 13, 463 Google Scholar
Brown, J. A., Sneden, C., Lambert, D. L., Dutchover, E., 1989, ApJS 71, 293 Google Scholar
Duncan, D. K., 1981, ApJ 248, 651 Google Scholar
Duncan, D. K., Jones, B. F., 1983, ApJ 271, 663 Google Scholar
Fekel, F. C., Balachandran, S., 1993, ApJ 403, 708 Google Scholar
Fekel, F. C., et al., 1995, in preparation Google Scholar
García López, R. J., Rebolo, R., Martín, E. L., 1994, A&A 282, 518 Google Scholar
Giampapa, M. S., 1984, ApJ 277, 235 CrossRefGoogle Scholar
Herbig, G. H., 1965, ApJ 141, 588 Google Scholar
Jeffries, R. D., Byrne, P. B., Doyle, J. G., Anders, G. J., James, D. J., Lanzafame, A. C., 1994, MNRAS 270, 153 Google Scholar
Martín, E. L., Claret, A., 1995, A&A, in press Google Scholar
Pallavicini, R., Cutispoto, G., Randich, S., Gratton, R., 1993, A&A 267, 145 Google Scholar
Pasquini, L., Liu, Q., Pallavicini, R., 1994, A&A 287, 191 Google Scholar
Patterer, R. J., Ramsey, L., Huenemoerder, D. P., Welty, A. D., 1993, AJ 105, 1519 CrossRefGoogle Scholar
Pilachowski, C. A., Sneden, C., Hudek, D., 1990, AJ 99, 1225 CrossRefGoogle Scholar
Pinsonneault, M. H., Kawaler, S. D., Demarque, P., 1990, ApJS 74, 501 Google Scholar
Randich, S., Gratton, R., Pallavicini, R., 1993, A&A 273, 194 Google Scholar
Robinson, R. D., Thompson, K., Innes, J. L., 1986, Proc. Astron. Soc. Australia 6, 500 Google Scholar
Skinner, C. J., Sylvester, R. J., Graham, J. R., Barlow, M. J., Meixner, M., Keto, E., Arens, J. F., Jernigan, J. G., 1995, ApJ 444, 861 Google Scholar
Skumanich, A., 1972, ApJ 171, 565 Google Scholar
Soderblom, D. R., Jones, B. F., Balachandran, S., Staufer, J. R., Duncan, D. K., Fedele, S. B., Hudon, J. D., 1993, AJ 106, 1059 CrossRefGoogle Scholar
Strom, K. M., Wilkin, F. P., Strom, S. E., Seaman, R. L., 1989, AJ 98, 1444 CrossRefGoogle Scholar
Traub, W., Roesler, F. L., 1971, ApJ 163, 629 Google Scholar