Kolokium Daring KK & Prodi Astronomi

Selasa, 9 Juni 2020, pukul 10.00 – 11.00 WIB

Study of eclipsing binaries: An apeal for closer collaboration in Stellar Astrophysics

Pembicara: Dr. Hakim L. Malasan

KK Astronomi & Obs. Bosscha, FMIPA, ITB
Prodi Sains Atmosfer & Keplanetan dan UPT OAIL, ITERA

Kami mengundang seluruh peminat kolokium untuk dapat bergabung melalui tautan:

Atas perhatian dan partisipasi aktifnya, kami sampaikan terima kasih.

Koordinator Kolokium,

Dr. Kiki Vierdayanti


Binary stars are important, because they are numerous. The observed frequency is about 20%, the actual frequency is higher because many binaries remain undetected. In solar neighborhood the frequency is more than 50% and several stars are in fact multiple systems (Kallrath & Milone, 1999). Binary stars are also important because they are primary source of our knowledge of fundamental properties of stars.
Short-period non-contact (SPNC) binaries are defined classically as eclipsing binaries with period of around one day, neither of the components in the system is a degenerate star, with spectral types ranging from A to F. Up to now less than 10 systems with parameters have been determined accurately. The involvement of Bosscha Observatory in this project, initiated by Yamasaki et al (1982), was due to 1983 where the photoelectric photometer attached to Bamberg refractor at Bosscha Observatory had been fully used to observe eclipsing binaries under collaboration with Okayama Astrophysical Observatory and Dodaira Observatory of the Tokyo (then became National) Astronomical Observatory of Japan. Among the SPNCs, the double-line detached eclipsing binaries, in particular, are interesting, since there is a discrepancy in the isotope 12C/13C that should be solved, may lead to a better understanding of binary formation and evolutionary path.
Nowadays with a small telescope equipped with CCD camera or spectrograph, we can contribute significantly to the science of stellar evolution, in particular close binaries, by observing and analyzing light curve and radial velocity curves of eclipsing binaries with these characteristics. Proper modeling could lead to answer unsolved questions related to evolutionary scenario of close binary stars.