COMMISSIONS 27 AND 42 OF THE IAU INFORMATION BULLETIN ON VARIABLE STARS Number 3797 Konkoly Observatory Budapest 28 October 1992 HU ISSN 0374 - 0676 First photoelectric BV lightcurves, improved position and ephemerides for the totally eclipsing EW type system V432 Per [BAV Mitteilungen Nr. 61] V432 Per = S 10154 Per was announced as a short period variable by Hoffmeister (Hoffmeister 1968a) with a range between 10.5 mag and 11 mag. He classified the star as a possibly eclipsing variable and gave two photographic plate minima (Hoffmeister 1968b). Pinto and Romano investigated the star in their photographic research. They confirmed the type of variability and found the range between 11.4 mag and 12.0 mag. They communicated six photographic plate minima, derived from them first elements as Min I = HJD 2438670.55 + 0.5271396 x E and published a first photographic light curve (Pinto and Romano 1976). Busch and Haussler (1979) investigated this star on plates of the Sonneberg sky survey and reported 32 minima. From these they derived new elements as Min I = HJD 2435874.376 + 0.321517 x E with a range between 11.0 mag and 11.7 mag. The type was given as EW. With these data V432 Per was included in the GCVS (Kholopov et al., 1987). Since that, eleven times of minimum light were published by the BBSAG (Diethelm 1990a, 1990b and 1991). The unusually large scatter in the O-C-Diagram, derived from the BAV Database of D. Lichtenknecker and the contradictory elements made V432 Per a candidate for the program of the author. The observations were made at the private observatory of the author with a 0.35 m automatic photoelectric telescope (Agerer 1988). The photometer was equipped with an uncooled EMI 9781A tube and Schott filters for B and V. Minimum timings are calculated using the Kwee-van Woerden method (Kwee, van Woerden 1956). V432 Per was observed on six nights between Dec. 1991 and Oct. 1992, mostly in two colors. SAO 038613 served as comparison star and SAO 038621 to check its constancy. Six primary and two secondary minima were observed (Table 1). The primary minima showed a constant phase of d = 25 min in V and somewhat less in B. The light in secondary minima was constant for 40 min in V and for 35 min in B. The amplitudes for the primary minimum were 0.62 mag in V and 0.74 mag in B. For the secondary minima the amplitudes were 0.36 mag (V) and 0.38 mag (B). [FIGURE 1] Figure 1: Differential B and V light and B-V colour curves for V432 Per. [FIGURE 2] Figure 2: (O-C) Diagram for V432 Per computed with respect to the ephemeris (1). [dot] represents photoelectric, o photographic, = visual observations and [square] photographic plate minima. Table 1: Observed times of minima for V432 Per, epochs and residuals computed with respect to the ephemeris derived in this paper. No. JD hel. Weight Type* Filter Epoch (O-C)1 (O-C)2 Observer Source 2400000+ 1 35874.370 0 P:: -33203. -0.001 0.115 [2] VSS 9.143 2 36460.505 1 P -31674. 0.055 0.166 [2] " 3 36852.601 1 P -30651. 0.026 0.133 [2] " 4 37946.555 1 P -27797. 0.017 0.114 [2] " 5 37959.581 1 P -27763. 0.010 0.107 [2] " 6 38240.553 1 P -27030. 0.017 0.111 [2] " 7 38289.609 1 P -26902. 0.009 0.103 [2] " 8 38317.592 1 P -26829. 0.011 0.104 [2] " 9 38322.569 10 F -26816. 0.005 0.098 [2] " 10 38325.637 10 F -26808. 0.006 0.100 [2] " 11 38331.587 10 F -26792.5 0.015 0.108 [2] " 12 38356.491 10 F -26727.5 0.004 0.097 [2] " 13 38370.465 10 F -26691. -0.013 0.080 [2] " 14 38371.278 10 F -26689. 0.034 0.127 [2] " 15 38373.353 10 F -26683.5 0.000 0.093 [2] " 16 38373.531 10 F -26683. -0.013 0.080 [2] " 17 38385.426 10 F -26652. -0.001 0.092 [2] " 18 38399.236 10 F -26616. 0.010 0.103 [2] " 19 38399.418 10 F -26615.5 0.000 0.093 [2] " 20 38406.495 10 F -26597. -0.014 0.079 [2] " 21 38410.346 10 F -26587. 0.004 0.097 [2] " 22 38439.290 10 F -26511.5 0.008 0.101 [2] " 23 38440.404 10 F -26508.5 -0.028 0.065 [2] " 24 38670.60 1 P -25908. -0.01 0.082 [1] AN 290.068277 25 39038.566 1 P -24948. -0.019 0.068 [2] VSS 9.143 26 39058.540 1 P -24896. 0.023 0.110 [2] " 27 39151.292 1 P -24654. 0.014 0.100 [2] " 28 39436.44 1 P -23910. -0.02 0.064 [1] AN 290.277 29 39527.281 1 P -23673. -0.023 0.060 [2] VSS 9.143 30 40624.295 1 P -20811. -0.039 0.034 [2] " 31 40863.492 1 P -20187. -0.027 0.044 [3] MSAI 47.236 32 40863.503 1 P -20187. -0.016 0.055 [3] " 33 41008.385 1 P -19809. -0.024 0.045 [3] " 34 41008.395 1 P -19809. -0.014 0.055 [3] " 35 41272.470 1 P -19120. -0.039 0.027 [3] " 36 41335.320 1 P -18956. -0.052 0.014 [2] VSS 9.143 37 41363.306 1 P -18883. -0.047 0.018 [2] " 38 41417.327 1 P -18742. -0.073 -0.008 [2] " 39 41657.316 1 P -18116. -0.035 0.028 [3] MSAI 47.234 40 41717.304 1 P -17959.5 -0.035 0.028 [2] VSS 9.143 41 47924.393 0 V:: -1766. -0.058 -0.052 [4] BBS 94 42 47929.376 0 V:: -1753. -0.058 -0.052 [4] " 43 47946.407 0 V:: -1708.5 -0.084 -0.078 [4] " 44 47956.355 0 V:: -1683. -0.089 0.095 [4] " 45 48128.548 5 V -1233.5 -0.015 -0.011 [5] BBS 96 46 48163.451 5 V -1142.5 0.007 0.011 [5] " 47 48176.474 5 V -1108.5 -0.002 0.001 [5] " 48 48189.435 0 V:: -1074.5 -0.074 -0.070 [4] " 49 48481.598 5 V -312.5 0.008 0.009 [5] BBS 98 50 48484.636 5 V -304.5 -0.021 -0.020 [5] " 51 48487.525 5 V -297. -0.007 -0.006 [5] " 52 48601.3739 20 E B 0. -0.0004 -0.0006 this paper 53 48601.3741 20 E V 0. -0.0002 -0.0004 " 54 48602.3331 20 E B 2.5 0.0005 0.0003 " 55 48602.3338 20 E V 2.5 0.0012 0.0010 " 56 48602.5246 20 E V 3. 0.0004 0.0002 " 57 48602.5247 20 E B 3. 0.0005 0.0003 " 58 48624.3711 20 E B 60. -0.0017 -0.0021 " 59 48624.3713 20 E V 60. -0.0015 -0.0019 " 60 48624.5662 20 E V 60.5 0.0017 0.0013 " 61 48624.5675 20 E B 60.5 0.0030 0.0026 " 62 48645.4552 20 E V 115. 0.0004 -0.0002 " 63 48832.5116 20 E B 603. 0.0021 -0.0002 " 64 48832.5118 20 E V 603. 0.0023 0.0000 " 65 48893.4584 20 E B 762. 0.0028 -0.0001 " 66 48893.4590 20 E V 762. 0.0034 0.0005 " [1]: C. Hoffmeister, [2]: H. Busch & K. Haussler, [3]: G. Pinto & G. Romano, [4]: H. Peter, [5]: J. Vandenbroere. (*) P denotes pg plate min., E photoel. min., F photographic series and V visual estimates. Those marked "::" were discarded. In compiling the light curve (Figure 1) it became evident, that the period given by Pinto and Romano, as well as the period given in the GCVS are spurious ones with the relations 1/P - 1/P_P&R = 5/7 and 1/P_GCVS - 1/P + 1/2 respectively. Using all available times of minima, a (weighted) least squares fit provided the following improved linear ephemeries: Min I = HJD 2448601.3743 + 0.38330885 x E (1) +/-6 +/-4 Instantaneous elements, computed from photoelectric minima only, are: Min I = HJD 2448601.3745 + 0.38331234 x E (2) +/-1 +/-22 Together with all previous minima, found in the BAV Database, this ephemeris indicates, there has been a distinct increase of the period since 1968 (Figure 2). In the course of this investigation the declination given by Hoffmeister and in the GCVS was found to be somewhat erroneous. From a copy of a Palomar Sky Survey print the position was redetermined through differential measurements against five SAO stars, distributed in a field of 1d x 1d around V432 Per as: alpha_2000 = 3^h 10^m 10.8^s delta_2000 = +42d 52' 12" +/-0.1^s +/-1" F. AGERER Berliner Arbeitsgemeinschaft fur Veranderliche Sterne e. V. (BAV) Munsterdamm 90 D-8000 Berlin 41 Germany References: Agerer F.: 1988, BAV Rundbrief 37(2), 60. Busch H., Haussler K.: 1979, Veroffentlichungen der Sternwarte in Sonneberg 9, 143. Diethelm R.: 1990a, BBSAG Bull. 94. Diethelm R.: 1990b, BBSAG Bull. 96. Diethelm R.: 1991, BBSAG Bull. 98. Hoffmeister C.: 1968a, Mitteilungen uber Veranderliche Sterne 4, 187. Hoffmeister C.: 1968b, Astronomische Nachrichten 290, 277. [BIBCODE 1968AN....290..277H ] Kholopov P. N. et al.: 1987, General Catalogue of Variable Stars, 4th Ed., Vol. III, Nauka, Moscow. [BIBCODE 1987gcvs.book.....K ] Kwee K. K., van Woerden H.: 1956, Bull. Astr. Inst. Netherlands, 12, 327. [BIBCODE 1956BAN....12..327K ] Pinto G., Romano G.: 1976, Memorie della Societa Astronomica Italiana 47, 229. [BIBCODE 1976MmSAI..47..229P ]