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تسجيل مستخدم جديدMarginally low mass ratio close binary system V1191 Cyg
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In this study, we present photometric and spectroscopic variations of the extremely small mass ratio ($qsimeq 0.1$) late-type contact binary system astrobj{V1191 Cyg}. The parameters for the hot and cooler companions have been determined as $M_textrm{h}$ = 0.13 (1) $M_{odot}$, $M_textrm{c}$ = 1.29 (8) $M_{odot}$, $R_textrm{h}$ = 0.52 (15) $R_{odot}$, $R_textrm{c}$ = 1.31 (18) $R_{odot}$, $L_textrm{h}$ = 0.46 (25) $L_{odot}$, $L_textrm{c}$ = 2.71 (80) $L_{odot}$, the separation of the components is $a$= 2.20(8) $R_{odot}$ and the distance of the system is estimated as 278(31) pc. Analyses of the times of minima indicates a period increase of $frac{dP}{dt}=1.3(1)times 10^{-6}$ days/yr that reveals a very high mass transfer rate of $frac{dM}{dt}=2.0(4)times 10^{-7}$$M_{odot}$/yr from the less massive component to the more massive one. New observations show that the depths of the minima of the light curve have been interchanged.
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