COMMISSIONS 27 AND 42 OF THE IAU INFORMATION BULLETIN ON VARIABLE STARS Number 3711 Konkoly Observatory Budapest 17 April 1992 HU ISSN 0374 - 0676 UBVR OBSERVATIONS AND NEW ELEMENTS FOR THE DOUBLE-MODE CEPHEID AS Cas Photoelectric observations of the double-mode Cepheid AS Cas were carried out in summer-autumn 1991. The 60-cm reflector of the Mt. Maidanak observatory of the Tashkent Astronomical Institute was used and 54 UBVR measurements (Table 1) were obtained. [FIGURE 1] Figure 1 The light curves of double-mode Cepheid AS Cas with period P(1) in different phase intervals of period P(0): 0-0.1 (a), 0.1-0.2 (b), 0.2-0.3 (c), 0.3-0.4 (d), 0.4-0.5 (e), 0.5-0.6 (f), 0.6-0.7 (g), 0.7-0.8 (h), 0.8-0.9 (i) and 0.9-1.0 (k) [FIGURE 2] Figure 2 The light curves of double-mode Cepheid AS Cas with period P(0) in different phase intervals of period P(1): 0-0.1 (a), 0.1-0.2 (b), 0.2-0.3 (c), 0.3-0.4 (d), 0.4-0.5 (e), 0.5-0.6 (f), 0.6-0.7 (g), 0.7-0.8 (h), 0.8-0.9 (i) and 0.9-1.0 (k) These observations supplemented with those published earlier (Berdnikov, 1992, Henden, 1980) allow to improve the periods using the method described by Antonello et al. (1986). The new elements are: Max (0) = JD hel 2448510.14 + 3.024675d E, and Max (1) = JD hel 2448510.5 + 2.155557d E. Table 1 JD hel 2448000+ V U-B B-V V-R 444.4515 12.292 - 1.390 1.232 445.4516 12.653 - 1.507 - 448.4434 12.324 - 1.415 - 455.4485 12.303 - 1.315 - 456.4464 12.160 - 1.291 1.159 461.4445 12.006 - 1.236 - 462.4542 12.290 - 1.344 - 463.4464 12.312 - 1.393 1.247 464.4536 12.339 - 1.367 1.241 465.4575 11.973 1.283 - - 466.4647 12.492 - 1.486 1.330 477.4503 12.222 - 1.340 1.209 479.4672 12.297 - 1.442 1.242 482.4514 12.147 - 1.295 1.183 485.4161 12.186 - 1.312 1.202 487.4259 12.309 0.800 1.401 1.250 490.4165 12.471 0.966 1.448 1.310 491.3749 12.190 0.923 1.303 1.221 494.3835 12.392 - 1.422 1.254 498.3969 12.111 - 1.287 1.202 499.3389 12.349 0.935 1.416 1.270 503.3517 12.551 - 1.454 1.297 504.3758 11.867 - 1.217 1.128 505.4105 12.469 - 1.443 1.296 506.4245 12.267 - 1.324 - 507.4144 12.189 - 1.327 - 508.3909 12.254 - 1.288 1.236 509.4098 12.460 1.021 1.387 1.306 510.3942 11.722 - 1.165 1.050 511.4153 12.291 - 1.408 1.253 512.4166 12.473 - 1.424 - 513.4157 12.040 - 1.276 - 514.4138 12.358 - 1.417 - 515.4136 12.342 - 1.343 1.243 516.3918 12.072 - 1.278 1.126 517.3929 12.177 - 1.347 1.186 520.3843 12.371 - 1.451 1.233 521.3643 12.414 - 1.374 1.250 522.2997 12.146 - 1.279 1.195 523.3380 12.228 - 1.337 1.225 533.3595 12.491 - 1.483 1.304 537.3231 12.112 0.887 1.279 1.165 541.3980 12.266 - 1.376 1.242 542.2482 12.467 1.133 1.464 1.260 543.2920 11.864 0.977 1.173 1.094 551.2763 12.454 - 1.478 1.267 552.2750 12.139 - 1.265 1.196 553.2429 12.200 - 1.300 1.200 556.2820 12.090 - 1.325 1.163 557.2307 12.573 - 1.443 1.342 559.2501 12.256 - 1.383 1.211 580.2376 12.324 - 1.387 1.202 561.2585 12.327 0.940 1.346 1.235 562.2889 12.029 0.897 1.256 1.174 The observed magnitudes converted into intensities were then expressed as a sum of two oscillations, and light curves of each oscillation were constructed for different phase intervals of the other oscillation. These curves in V band are presented in Figures 1 and 2. A detailed investigation of the light curves of AS Cas in UBVR bands will be published elsewhere. L. BERDNIKOV and S. SKORNYAKOVA University of Saratov, Saratov, Russia M. IBRAGIMOV, V. KONDRATIEV and S. YAKUBOV Astronomical Institute, Tashkent, Republic of Uzbekistan References: Antonello, E., Mantegazza, L. and Poretti, E.: 1986, Astron. Astrophys., 159, 269. [BIBCODE 1986A&A...159..269A ] Berdnikov, L.N.: 1992, submitted for publication. Henden, A.A.: 1980, Mon. Not. Roy. Astron. Soc., 192, 621. [BIBCODE 1980MNRAS.192..621H ]