Zeinab Ahmed Mabrouk <br/><br/>
The evolution of binary neutron star orbits due to the emission of gravitational waves /  
 تطور مدارات النجوم النيوترونية المزدوجة نتيجة إنبعاث موجات التثاقل 
Zeinab Ahmed Mabrouk ; Supervised Mustafa Kamal Mahmoud Ahmed , Shahinaz Mostafa Ali Yousef , Walied Ali Ahmed Hassan Rahoma 
 - Cairo :   Zeinab Ahmed Mabrouk ,   2017 
 - 74 P. :   charts , photographs ;   25cm 
<br/><br/>Thesis (M.Sc.) - Cairo University - Faculty of Science - Department of Astronomy and Meteorology 
<br/><br/> We have applied the method derived by (imshennik and popov) of  determination the elliptical orbits evolution due to gravitational wave emission  on two different systems. The first is the Pre-supernova SN1987A, it was the same system that Imshennik and popov used. With the aid of mathematica programme, we got the same curves and conclusions; however we added some curves in order to ensure the gotten results. The second system was PSR1913+16 system. Our results for this system are highly comparable with the latest analysis for that system based on published timing observations from 1974 through 2006 (weisberg, nice and taylor, 2010). The most important results from our study are: Both our studied elliptical orbits shrink in size and become near circular at their late stages of evolution while the circular orbits dont change its shape; and most of the energy is lost at high eccentricities near the periastron position 
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<br/><br/><label>Subjects--Index Terms: </label>Evolution of neutron star orbits Gravitational waves PSR 1913+16