2015BAVSR..64...69R

Primary minimum and the first detection of secondary minimum of the large amplitude Algol sytem PX Cep are presented here. All 512 data have been observed in mountain Ossiacher Tauern, Koestenberg, Austria, using CCD-technique. The data were acquired in a time span over 168 days between 17.06.2013 and 01.12.2013 using an Apogee U16M CCD-camera and an Apo 130 f/9.2 refracting telescope. The simulation of the system was carried out by manual calculation and use of BinaryMaker3, developed by D. Bradstreet. In table 1 can be see the heliocentric corrected Julian date HJD of primary minium, table 2 shows the magnitudes and amplitudes of minimums in the three photometric bassbands of Johnson/Cousins B, V and Rc. Table 3 shows the parameters of the system including radius, (B-V)colour index of both stars and inclination of the binary system. First column of table 3 shows the solution of manual calculations and the second column shows the solution of BinaryMaker3. Irregularities in lightcurves led to the adoption of mass transfer and hot-spots on the primary star.