Naslov
Globalna optimizacija genetickim algoritmom i model masivne dvojne zvijezde V356 Sagitarii
(Global optimization with Genetic Algorithm and model of the massive binary system V356 Sagitarii)

Autori
Dominis, Dijana

Vrsta, podvrsta i kategorija rada
Ocjenski radovi, magistarski rad

Fakultet
Prirodoslovno-matematicki fakultet

Mjesto
Zagreb

Datum
14.05

Godina
2001

Stranica
76

Mentor
Pavlovski, Kresimir

Ključne riječi
dvojne zvijezde; svjetlosne krivulje; geneticki algoritam; V356 Sgr
(binary stars; light curves; genetic alghoritm; V356 Sgr)

Sažetak
The eclipsing, interacting binary system, V356 Sgr is of considerable interest since it is probably at the very end of its mass transfer phase, i.e. between Beta Lyrae on the one side, and Algol, on the other. Hence, reliable astrophysical parameters describing the binary and its components are needed. We have examined two models: (i) model with an accretion disk surrounding a hotter and more massive component, and (ii) model with a fast rotating hotter component. The calculations were performed with a light-curve synthesizing code which includes the presence of an accretion disk and an arbitrary rotating stellar component. A novel optimizing method using a Genetic Algorithm has been implemented into the light-curve synthesizing code.Such a method was necessary due to a complex multi-dimensional parameter space with many local minima. The new method has been tested using synthesized light-curves and proved to be successful in search for the global minimum. It has been applied on the photometric observations of a bright eclipsing binary V356 Sgr published by Popper (1955, 1957) and found that the model with a disk better matches the observations. The set of optimized parameters for the disk model could be used in forthcoming calculations with more sophisticated models.

Izvorni jezik
Hrvatski

Znanstvena područja
Fizika

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