COMMISSION 27 OF THE I. A. U. INFORMATION BULLETIN ON VARIABLE STARS NUMBER 488 Konkoly Observatory Budapest 1970 November 11 PHOTOELECTRIC OBSERVATIONS OF EV Lac Photoelectric monitoring of EV Lac was carried out at the Byurakan Observatory with the 50 cm reflector in the time interval 23 August - 9 September 1970, proposed by the "working group" (IBVS 416). The observations were made with a standard B filter. From the experience achieved during a statistical investigation of flare data, we thought it more opportune to present our observational data in a form which seems to be more convenient from the point of view of further statistical and other investigations. Denoting by UT_max - the UT of the maximum, t_b - the duration of the light increase in minutes, t_a - the duration of the light decrease in minutes, X_S - the deflection - for a fixed sampling time interval - due to the normal radiation of the star, X_s - the mean value of X_s (in the case of a flare this value is calculated from the X_s immediately preceding the flare), sigma - the standard deviation of X_s, X_f - the deflection due to the radiation of the flare itself, X_fM - the maximum deflection of the flare, P - the value of summa_t1^t2(X_f/X_s)dt in minutes (t_1 and t_2 being the moments of the beginning and the end of the flare), F(z) - the air mass at the moment of the flare, we can present the observational data in the following form: Table I Data Coverage UT_max t_b t_a X_fM/X_s sigma/X_s P F(z) Remarks UT UT 1970 Aug. 23 1731-2045 1 2100-2220 24 1800-2200 1 2209-2309 2 25 1700-2200 1 2208-2400 26 0000-0008 1 27 1745-1855 0.026 1912-2130 20h37m3 0.63 3.33 0.56 0.026 0.74 1.03 2 2145-2200 0.026 4 28 1811-2133 0.021 2 2135-2310 0.021 31 1849-1915 0.019 2 1920-2120 0.019 2125-2207 0.019 Sept. 1 1647-2110 19 43.1 0.21 0.29 0.15 0.028 0.03 1.04 3 2119-2400 21 24.9 1.04 2.50 0.51 0.018 0.63 1.01 2 0000-0033 0.018 3 1826-1904 0.011 2 1915-2019 0.011 2155-2230 0.011 4 1630-1713 0.019 2 1718-1728 0.019 1918-1954 0.019 2210-2310 0.019 5 1633-2100 0.016 2105-2309 0.019 6 0000-0120 0.019 2 1748-2050 0.019 2055-2308 0.019 8 1923-2040 16 55.0 0.66 0.94 0.79 0.029 0.39 1.32 2055-2400 0.029 9 0000-0100 0.020 1624-1820 0.020 1824-2040 18 28.4 1.12 2.23 0.99 0.020 0.97 1.09 2049-2400 0.020 10 0000-0100 0.020 [FIGURE 1] [FIGURE 2] [FIGURE 3] [FIGURE 4] [FIGURE 5] Remarks 1. - The instability of the measuring device did not allow the detection of flares with X_fM/X_s < 0.45 2. - Cloudy. 3. - Possible flare. 4. - The connection between Delta m and X_f/X_s is given by Delta m = 2.5 log (X_f/X_s+1) Total coverage 4296 minutes. The light curves of observed flares are presented in the figures. The ordinate is given in the units of X_f/X_s V. S. OSKANIAN Byurakan Observatory USSR Correction to IBVS No. 176: Star name Printed Correctly RW CMa 28201.83+5.72941 E 27021.68+5.72906 E RW Cas 37168.23 37158.23 UX Per 4.97247 E 4.56581 E