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Photoelectric Observations of Southern Long Period Variable Stars

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Photoelectric Observations of Southern Long Period Variable Stars w Astron. & Astrophys. 12,143-143 (1971) Photoelectric Observations of Southern Long Period Variable Stars M. WISSE and P. N. J. WISSE Republic Observatory, Johannesburg Beceived November 18,1970 VBV observations of six long period variables of different types are presented. They are: ons> Mira star (S Car), two SRb type stars (RR Car, SW Vir), pno RV Tauri (!) star (IW Car) and two irregular ones (RW Vir, V Hya). The results are in good agreement with earlier observations by Smak (1964). Key words: long period variable stars 1. Introdnction The present paper gives the first results of a season The Long Period variable stars (hereinafter re- devoted entirely to the study of LPVS. The stars are ferred to as LPVS) form a large and rather inhomo- selected from the general catalogue of variable stars geneous subdivision of the family of variable stars. (GCVS) (Kukarkin et al., 1958, 1969), using the They have a wide range of periods and amplitudes, criterion that they must have a minimum brighter and a large number have no period at all. Extensive than m M 10. Thus we must be able to cover the whole work with respect to the spectra of LPVS has been range of the variation. ft- carried out. Reviews of the spectral characteristics have been given by Merrill (1960) and Ledoux and I Walraven (1958). Extensive work as regards the 2. Observations and Seductions light curves is carried out by amateur astronomers all The observations were made with the 50-cm Boiler over the world (see e.g. Campbell, 1955). Photoelectric and Chivens Cassegrain reflector of the Republic observations however are scanty, and most previous Observatory and a VBV photometer consisting of an observations refer to the maximum or near-maximum unrefrigerated EMI 6685 photomultiplier and 2 mm phases only (see e.g. Eggen, 1961; Smak, 1964: Evans, UG 2 (V), 1 mm BG12 + 2 mm GG13 (.B) and 2 mm 1970). A review is given by Smak (1966). For a sum- OG i (V) filters. The natural system has been trans- mary of problems of LPVS see Wing (1967). formed to the VBV system using a method described Table 1. Data an, variables and comparison stars Star B—V U—B SCar 10»08m241 _61=24° CPD—60-1646 10 01 45 —6100 +7"?07 +1"?42 +l"P70 KRCar 9 67 06 —58 40 CPD—58=1781 9 69 18 —58 62 +7.89 +1.55 +1.78 IWCar 9 26 11 —63 30 CPD—63=1122 9 23 45 —63 33 +8.62 +0.62 +0.09 UHya, 10 35 60 —1314 SAO 156170 10 40 40 —13 47 +6.42 +1.51 +1.83 EWVir 12 05 42 —06 36 SAO 138679 12 03 60 —05 41 +6.77 +1.53 +1.84 SWVir 13 12 31 —02 39 SAO 139224 13 11 30 —02 65 +9.44 +1.62 +1.86 SAO = Smithsonian Astrophysical Obs. star catalogue* 144 M. Wiaae and F. N. J. Wisse Astron. & Aitiophyi. Table 2. Individual Obstrvatiwia A indicates (variable — Table 2 (continued) comparison} RRCarinae SCarinae JD A{Y-B) A{U-B) JD AY A(B-V) A(JJ-B) 2440000 2440000 747.213 —07190 +07085 —07845 701240 +17029 +0"?155 —07216 754.206 —0201 +0.122 -O.960 703267 +0.903 +0.147 —0.239 .758208 —0.174 +0.102 —0.981 705.238 +0.772 +0.129 -0.253 760.187 —0.180 +0.081 —0.872 706.259 +0.696 +0.135 —0226 762.195 —0.133 +0.090 —0.912 708.260 +0.549 +0.129 —0239 709.259 +0.498 +0.096 —0.350 713.233 +0207 +0.087 -0.264 IWCsrinae 715.232 +0.076 +0.041 -0.229 JD AY A[B-V) A{U-B) 718.256 -O.120 +0.042 —0.315 2440000 722.243 -0.321 —O.004 —0.403 723.227 -0.374 —0.003 —0.233 725.263 —0.421 669.318 —07154 +0™302 +07824 —0.420 +0.017 —0.109 +0.387 +C.8I4 726218 -0.440 —0.003 —0.440 660.241 727.216 -0.449 —0.021 —0.525 682.314 —0.110 +0.397 +0.833 728.234 —0.497 —0.017 —0.464 683216 —0.130 +0.394 +0.717 729.228 -0.513 —0.029 -0.493 686.359 —0.147 +0.364 +0.746 733214 -0.595 -0.049 —0.595 £90.251 —0.180 735221 -4.640 —0.052 —0.667 695.253 —0279 +0.307 +0.847 737227 —0.712 —0.055 -0.694 698.219 —0.347 +0.242 +0.625 740233 —0.849 —0.061 —0.777 701.214 —0.460 +0.203 +0.691 742202 -0.936 —0.076 —0.767 702.213 —0.466 +0.157 +0.545 744.223 —1.048 —0.063 —0.859 703244 —0.485 +0.170 +0.595 746207 —1.130 —0.063 —0.881 704223 —0.494 +0.152 +0.554 754220 —1.262 0.000 —0.887 705.202 —0.519 +0.131 +0.591 .758.223 —1.318 +0.083 —0.871 706.218 —0.527 +0.132 +0.587 760.203 —1.336 +0.117 —0.796 708.224 —0.544 +0.132 +0.572 763.196 —1.397 +0.152 —0.769 709216 —0.516 +0.137 +0.564 768.198 —1.468 +0.183 —0.694 713.193 —0.526 +0.136 +0.604 770.191 —1.448 +0240 —0.765 714217 —0.514 +0.137 +0.645 772.191 +0.248 —0.688 715201 —0.492 +0.135 +0.654 717248 —0.491 +0.158 +0.606 718.226 —0.479 +0.165 +0.587 722.205 —0.468 +0.191 +0.626 RRCarinae 723.199 —0.410 +0.200 +0.642 JD AY A(B-V) A(U-B) 726.188 —0.368 +0.226 +0.658 2440000 727.188 —0.374 +0.241 +0.664 728206 —0.351 +0.244 +0.676 704240 —07599 +07073 —07715 729.197 —0.334 +0252 +0.682 705221 -0.607 +0.078 —0.828 733.187 —0.256 +0.270 +0.713 708.242 —0.610 +0.096 -0.629 735.193 —0256 +0.296 +0.694 709241 —0.593 +0.084 —0.476 737.198 —0201 +0296 +0.701 713216 -0.693 +0.050 —0.664 740202 —0.193 +0.320 +0.711 715.217 —0.676 +0.100 —0.736 741.193 —0.184 +0.311 +0.696 718.241 —0.529 +0.096 —0.304 743.209 —0.151 +0.291 +0.672 723213 -0.469 +0.077 —0.692 745.189 —0.125 +0.335 +0.761 726202 —0.418 +0.090 —0.723 754.191 —0.146 +0.339 +0.767 727202 —0.440 +0.091 -0.646 758.191 —0.181 +0.339 +0.704 728220 —0.402 +0.098 —0.713 729.214 -0.399 +0.102 -0.738 733.200 —0.349 +0.093 —0.767 RW Virginia 735.208 -0.332 +0.083 —0.818 JD AY A(B-V) A{V-B) 737.213 —0.309 +0.083 —0.834 2440000 740.176 -0.283 +0.085 —0.778 742.188 —0.249 +0.103 -0.587 714293 +07613 -07044 —07784 744208 —0228 +0.091 -0.855 717.307 +0.562 —0.024 —0.767 746.193 -0.247 +0.091 —0.858 718.303 +0.664 —0.026 —0.767 Vol. 1!, No. 1,1871 Long Period Variables 145 Table 2 (continued) Table 2 (continued) RW Virginia TJHydrae JD A (B-V) A(U-B) JD AV A (B-V) A(U-B) 2440000 2440000 +07428 —07030 —0?723 714.245 —17447 +17101 +27831 +0.404 -0.004 —0.730 717562 —1.456 +1.106 +3.149 +0.346 —0,007 —0.667 718.287 —1.455 +1.121 +3.426 +0.234 +0.011 —0.595 728.278 —1.484 +1.108 +3.409 +0.239 +0.011 —0.648 729.273 —1.483 +1.109 +2.954 +0581 +0.016 —0.645 735536 —1.511 +1.106 +3.048 +0529 +0.024 —0.642 737560 —1.505 +1.077 +3.111 +0.231 +0.030 —0.633 741.248 —1.514 +1.075 +3.803 +0503 +0.029 —0.629 743543 —1.524 +1.071 +3.315 +0.295 +0.031 —0.683 744.257 —1.509 +1.061 +3.398 +0569 +0.014 —0.648 745.224 —1.522 +1.068 +3.375 +0561 +0.017 -0.639 746.239 —1.515 +1.074 +3.233 +0.251 +0.020 —0.648 758.254 —1.502 +1.073 +3.100 +0.316 +0.016 —0.648 760530 —1.483 +0.31S +0.OM —0.648 761.198 —1.539 +1.081 +3.231 +0.299 +0.002 —0.664 762525 —1.494 +1.042 +3.111 AV A(B-V) A{U~B) by Hardie (1962). Southern standard stars have been selected from a list given by Cousins and Stoy (1963). 27323 +07046 —17199 Although the atmospheric conditions sometimes U 7061350 —2.349 +0.037 —1.164 changed rapidly, mean extinction coefficients have f; 709.323 —2566 +0.011 —1510 been used in the computation of magnitudes and I 714525 —2348 +0.026 —1.201 U 717.336 —2.345 +0.024 —1.191 colours of the comparison stars. |; 718.334 —2.335 +0.013 —1514 Comparison stars were selected as close to the f. 728.341 —2535 +0.013 —1501 variable as possible and preferably of the same | 729536 —2505 +0.017 —1.044 spectral type.
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