OSCILLATIONS IN TW DRACONIS

Автор(и)

  • M. Zejda Institute of Theoretical Physics and Astrophysics, Masaryk University, Kotlarska 2, CZ-611 37 Brno, Czech Republic, Чехія
  • Z. Mikulasek Institute of Theoretical Physics and Astrophysics, Masaryk University, Kotlarska 2, CZ-611 37 Brno, Czech Republic; Observatory and Planetarium of J. Palisa, VSB - Technical University, Ostrava, Czech Republic, Чехія

DOI:

https://doi.org/10.18524/1810-4215.2007.20.87220

Ключові слова:

Stars, binary, eclipsing, stars, individual, TW Dra.

Анотація

TW Draconis is one of the well-know known and studied Algol-like eclipsing binaries. The light variations of TW Dra are caused predominantly by eclipses of the hot main sequence star A8V by the cooler and fainter giant component K0 III. The total primary minimum deep 2.3 mag in B takes 11.5 hours and repeats with the orbital period about 2.807 days. We target our analysis to the study of oscillations in the system of all kind. Combining all available timings of minima we found oscillations of orbital period manifesting in O-C values variations. We speculate they are caused by the mass and angular momentum transfer and the presence of the third body in the system. Our photometric observations confirm also previously revealed oscillations in the light curve. Delta Scuti-like oscillations of the primary component cannot be the only explanation of them, as we found these small light variations also in the bottom of the totality. The complete paper is to be published elsewhere.

Посилання

Al-Naimiy , H. M. K., Al-Sikab, A. O., 1984, Astroph. Space Sci, 103, pp. 115-124

Applegate, J. H., 1992, ApJ, 385, p. 621-629

Applegate, J. H., Patterson, J., 1987, ApJ, 322, L99-L102

Baglow, R.L., 1952, Publ. David Dunlap Obs., 2, No. 1

Kwee, K. K., van Woerden, H., 1958, BAN,12, 357

Lanza, A. F., Rodono, M., Rosner, R., 1998, MNRAS, 296, pp. 893-902

Lanza, A. F. 2006, MNRAS, 369, pp. 1773-1779

Matese, J. J., Whitmire, D. P ., 1983, A&A, 117, L7-L9

Papouˇ sek, J., T remko, J., V ete ˇ sn ´ ık, M., 1984, F olia F acultatis scientiarum naturalium Universitatis Purkynianae Brunensis; tomus 25, opus 4.Physica 42

Singh, K. P ., Drake, S. A., White, N. E., 1995, Astroph. J., 445, pp. 840-854

Umana, G., Catalano, S., Rodono, M., 1991, A&A, 249, 217

Walter, K., 1978, A&AS, 32, 57

White, N. E., Marshall, F. E., 1983, ApJ, 268, L117

##submission.downloads##

Опубліковано

2007-12-22

Номер

Розділ

Статті