Physical Parameters of the Eclipsing Binary System EPIC 202060577

EPIC 202060577 is an eclipsing binary system containing a B-type primary star. From the K2 photometry, 45 secondary minimal times were obtained. The orbital period is determined to be 1.019648 days and the epoch formula is derived. Based on LAMOST (Large Sky Area Multi-Object Fiber Spectroscopic Telescope) spectra,the ROTFIT program is used to obtain spectral class, effective temperature, metal abundance and surface gravity of the primary star, and calculate the radial velocities.Through the PHOEBE (Physics Of Eclipsing Binaries) modeling program and emcee(Affine Invariant Markov chain Monte Carlo Ensemble Sampler) fitting program, a solution of the orbital parameters is obtained and the influence of Rossiter-McLaughlin effect on the radial velocity curve is analyzed. The final solution shows that EPIC 202060577 is a detached eclipsing binary system with mass ratio q=0.11, the spectral class of the primary star is B2/3. The mass, radius and effective temperature of the primary and secondary stars are M 1 =12.56M ⊙ and M 2 = 1.39M ⊙ , R 1 =4.58R sun and R 2 =1.85R sun , T 1 =18979 K and T 2 =8710 K, respectively, here M ⊙ and R sun are the solar mass and solar radius. According to the physical parameters, the evolutionary phase of EPIC 202060577 is discussed.