Zamanov, R. K.Martí Ribas, JosepParedes i Poy, Josep MariaFabregat, JaimeRibó Gomis, MarcTarasov, A. E.2013-08-282013-08-2819990004-6361https://hdl.handle.net/2445/45407We present the results of analyzing H$\alpha$ spectra of the radio emitting X-ray binary LS I+61303. For the first time, the same 26.5 d radio period is clearly detected in the H$\alpha$ emission line. Moreover, the equivalent width and the peak separation of the H$\alpha$ emission line seem also to vary over a time scale of 1600 days. This points towards the $\sim4$ yr modulation, detected in the radio outburst amplitude, being probably a result of variations in the mass loss rate of the Be star and/or density variability in the circumstellar disk. In addition, the dependence of the peak separation from the equivalent width informs us that the LS I+61303 circumstellar disk is among the densest of Be-stars.8 p.application/pdfeng(c) Springer Verlag, 1999EstelsEstels binaris de raigs XRadioastronomiaAstrofísicaStarsX-ray binariesRadio astronomyAstrophysicsinfo:eu-repo/semantics/article1527702013-08-28info:eu-repo/semantics/openAccess