Light curves analysis of four W Uma-type stars
Other Title(s)
تحليل المنحنيات الضوئية لأربع نجوم من كوكبة الدب الأكبر
Dissertant
Thesis advisor
Comitee Members
Salih, Salah A.
al-Abbudi, Bushra Qasim
Ahmad, Muhammad S.
University
University of Baghdad
Faculty
College of Science
Department
Astronomy and Space Department
University Country
Iraq
Degree
Master
Degree Date
2011
English Abstract
W Ursae Majoris stars are easily recognized by their light curves with near equal minima and by their continuous light variation.
In general, the periods of these systems are typically short and range between (0.2 day to around 0.7 day) and mass ratio (0.072-1).
Each of the components in the binary system is of nearly the same spectral type, from around middle A to early K, with the huge part concentrated in middle F through early G.
The stars are assumed to be in a similar evolutionary state, located near or just above the zero age main sequence .
In this work, the systems (W UMa, V839 Oph, V566 Oph in both blue and yellow filters and VW Cep in yellow filter only) have been chosen.
The light curve for each system analysed separately using Kopal’s method which is based on Fourier transforms in frequency domain.
The observations which represent the primary and the secondary minima for each system are used to calculate the moment areas and Fourier coefficients, from these moment areas, the light curve elements which are the fractional radii, the fractional luminosities and the inclination angle are determined.
The results have been compared with previous studies, and our results indicated that the selected systems are contact systems
Main Subjects
No. of Pages
80
Table of Contents
Table of contents.
Abstract.
Abstract in Arabic.
Chapter One : General introduction.
Chapter Two : Fourier analysis of the light curves in frequency domain.
Chapter Three : Results and analysis.
Chapter Four : Conclusions and future works.
References.
American Psychological Association (APA)
Nahi, Nimah Abd Allah. (2011). Light curves analysis of four W Uma-type stars. (Master's theses Theses and Dissertations Master). University of Baghdad, Iraq
https://search.emarefa.net/detail/BIM-603884
Modern Language Association (MLA)
Nahi, Nimah Abd Allah. Light curves analysis of four W Uma-type stars. (Master's theses Theses and Dissertations Master). University of Baghdad. (2011).
https://search.emarefa.net/detail/BIM-603884
American Medical Association (AMA)
Nahi, Nimah Abd Allah. (2011). Light curves analysis of four W Uma-type stars. (Master's theses Theses and Dissertations Master). University of Baghdad, Iraq
https://search.emarefa.net/detail/BIM-603884
Language
English
Data Type
Arab Theses
Record ID
BIM-603884
