COMMISSION 27 OF THE I. A. U. INFORMATION BULLETIN ON VARIABLE STARS NUMBER 180 Konkoly Observatory Budapest 25 January 1967 MINIMA OF ECLIPSING VARIABLES This report continues the one in IBVS No. 154, and contains 151 observed minima of 41 eclipsing variable stars. All are visual timings reduced by the tracing-paper method, except where noted. Linear elements in the 1958 General Catalogue of Variable Stars were used to compute the O-C's, unless otherwise specified. The number of estimates used for each minimum is given under n. J. D. hel E O-C n Observer (2430000) RT Andromedae 9323.664 +24,175 -0.015 17 Carl Anderson 9340.643 +24,202 -0.017 19 D. Lucas 9350.712 +24,218 -0.011 12 F. Sanner 9355.740 +24,226 -0.014 13 F. Sanner XZ Andromedae 9349.696 + 4,764 +0.053 17 M. Baldwin 9353.766 + 4,767 +0.051 15 R. Swanberg 9421.634 + 4,817 +0.056 24 D. Livingston 9421.635 + 4,817 +0.057 13 D. Williams 9421.637 + 4,817 +0.059 30 F. Chapman 9425.707 + 4,820 +0.057 19 M. Baldwin AB Andromedae 9316.819 +12,779.5 +0.056 14 M. Baldwin 9348.682 +12,875.5 +0.058 10 M. Baldwin 9349.676 +12,878.5 +0.056 13 M. Baldwin 9352.662 +12,887,5 +0.055 10 M. Baldwin 9426.675 +13,110.5 +0.057 12 M. Baldwin 9432.650 +13,128,5 +0.058 8 M. Baldwin 9433.646 +13,131,5 +0.059 9 M. Baldwin 9435.637 +13,137,5 +0.058 12 M. Baldwin 9435.804 +13,138 +0.059 12 M. Baldwin 9436.632 +13,140.5 +0.058 10 M. Baldwin CX Aquarii 9358.592 +23,431 +0.034 12 R. Monske 9378.594 +23,467 +0.021 16 R. Monske J. D. hel E O-C n Observer (2430000) BV 623 Aquarii 8990.0584 \1/ + 8,143 +0.0095 27pe L. Kalish 8990.8241 \1/ + 8,143.5 +0.0126 17pe L. Kalish OO Aquilae 9293.841 + 9,999 -0.023 10 M. Baldwin 9315.642 +10,042 -0.014 7 M. Baldwin 9316.649 +10,044 -0.021 11 M. Baldwin 9317.660 +10,046 -0.024 11 M. Baldwin 9319.689 +10,050 -0.022 14 M. Baldwin 9320.701 +10,052 -0.023 13 M. Baldwin 9337.677: +10,085.5 -0.025 13 R. Monske 9342.747 +10,095.5 -0.023 14 R. Monske 9350.602 +10,111 -0.023 13 R. Monske 9352.626 +10,115 -0.027 10 M. Baldwin 9355.664 +10,121 -0.029 12 R. Monske 9355.665 +10,121 -0.028 16 M. Baldwin V342 Aquilae \1/ 9318.584 + 1,087 +0.010 33 M. Baldwin V346 Aquilae 9341.659 + 7,242 -0.023 21 R. Monske 9342.769 + 7,243 -0.019 20 R. Monske WW Aurigae 9169.712 + 2,339 +0.001 18 M. Baldwin AR Aurigae 9435.856 + 3,070 +0.014 14 M. Baldwin Y Camelopardalis 9173.706 + 4,459 -0.014 25 M. Baldwin 9183.617 + 4,462 -0.020 16 L. Hazel SV Camelopardalis 9348.739 +11,906 -0.021 10 F. Sanner 9361.790 +11,928 -0.018 11 F. Sanner R Canis Majoris 9169.678 + 3,217 +0.005 14 M. Baldwin J. D. hel E O-C n Observer (2430000) RZ Cassiopeiae 9315.748 +18,373 -0.038 18 M. Baldwin 9321.726 +18,378 -0.037 10 T. Cragg 9327.697 +18,383 -0.042 45pe A. Stokes 9364.756: +18,414 -0.036 14 R. Thompson 9364.757 +18,414 -0.035 18 F. Sanner 9375.505 \3/ +18,423 -0.044 12 J. Ashbrook 9385.677 \4/ +18,431.5 -0.032 30pe J. Ruiz 9393.436 \3/ +18,438 -0.039 6 J. Ashbrook 9400.609 +18,444 -0.040 14 R. Thompson 9406.584 +18,449 -0.042 15 R. Thompson 9419.733 +18,460 -0.040 15 Sterling Anderson 9425.713 +18,465 -0.039 9 M. Baldwin 9431.688 +18,470 -0.038 15 T. Cragg 9443.646 +18,480 -0,032 9 J. Ashbrook 9456.779 +18,491 -0.047 33 D. Friedman TV Cassiopeiae \5/ 4261.516: + 7,803 -0.023 5 J. Ashbrook 5662.683: + 8,576 -0.003 10 J. Ashbrook 6108.584 + 8,822 -0.004 5 J. Ashbrook 7132.711 + 9,387 -0.002 14 J. Ashbrook 8274.659 +10,017 +0.002 16 J. Ashbrook 9338.655 +10,604 -0.004 11 J. Ashbrook 9358.596 +10,615 -0.001 7 J. Ashbrook AB Cassiopeiae 9432.593 +10,203 +0.064 19 M. Baldwin 9436.694 +10,206 +0.065 21 M. Baldwin U Cephei 8909.773 +12,443 +0.742 12 D. Williams 9435.805 +12,654 +0.779 34 M. Baldwin XX Cephei 9433.569 + 6,134 -0.091 14 M. Baldwin EG Cephei \4/ 9358.785 +22,822 +0.005 14 R. Monske J. D. hel E O-C n Observer (2430000) BV 382 Cephei \6/ 8606.7068 + ,407 -0.0006 37pe J. Ruiz 8622.636 + 427 +0.014 18pe A. Stokes 8634.795 + 437 +0.002 27pe A. Stokes 8642.759 + 445.5 +0.009 33pe A. Stokes 8644.635 + 447.5 +0.013 --pe A. Stokes 8649.757 + 453 -0.014 --pe A. Stokes 8652.585 + 456 +0.005 19pe A. Stokes 8652.588 + 456 +0.008 89pe J. Ruiz 8694.7047 + 501 -0.0028 40pe J. Ruiz 8700.7885 + 507.5 -0.0041 27pe J. Ruiz 8703.6015 + 510.5 +0.0004 30pe J. Ruiz 8708.7487 + 516 -0.0013 26pe J. Ruiz 8711.5587 + 519 +0.0002 17pe J. Ruiz 8997.0911 \7/ + 824 +0.0004 --pe J. Ruiz 8997.5592 \7/ + 824.5 +0.0004 --pe J. Ruiz 9405.7367 + 1,260.5 +0.0074 --pe A. Stokes Y Cygni \8/ 9293.768 + 9,932 +0.007 16 M. Baldwin 9341.702 + 9,948 0.000 18 R. Monske 9350.690 + 9,951 +0.001 18 R. Monske 9134.588 + 9,979 -0.001 14 R. Monske V477 Cygni 9356.826 + 2,774 -0.041 13 F. Sanner 9429.592 + 2,805 -0.032 14 F. Sanner W Delphini 9358.695 + 4,434 +0.101 30 R. Monske YY Delphini 9355.702 +17,098 +0.036 13 R. Monske AI Draconis 9342.729: +12,266 +0.012 20 R. Monske TW Draconis 9350.621 + 1,946 0.000 20 R. Monske RX Herculis 8966.763 + 3,259 -0.006 13 D. Williams 8998.795 + 3,277 +0.011 19 D. Loring J. D. hel E O-C n Observer (2430000) SZ Herculis \9/ 9293.839 + 2,649 +0.009 17 M. Baldwin 9312.660 + 2,672 +0.014 11 M. Baldwin 9316.746 + 2,677 +0.009 20 M. Baldwin 9347.841: + 2,715 +0.017 19 Curtis Anderson 9348.654 + 2,716 +0.012 11 M. Baldwin 9352.744 + 2,721 +0.011 23 R. Swanberg 9366.654 + 2,738 +0.013 20 W. Lowder 9375.653 + 2,749 +0.013 15 W. Lowder CT Herculis 8894.754 + 4,473 +0.038 22 R. Monske 8953.728 + 4,506 +0.062 19 R. Monske 9321.739 + 4,712 +0.088 11 T. Cragg 9355.666 + 4,731 +0.075 17 R. Monske SW Lacertae 9335.773 +49,773 +0.036 19 R. Swanberg 9344.910 +49,801.5 +0.033 18 D. Loring 9348.766 +49,813.5 +0.040 14 R. Swanberg 9349.729 +49,816.5 +0.041 20 M. Baldwin 9352.772 +49,826 +0.037 15 R. Swanberg 9426.705 +50,056.5 +0.046 13 M. Baldwin 9429.591 +50,065.5 +0.045 11 M. Baldwin 9429.592 +50,065.5 +0.046 12 R. Monske 9432.638 +50,075. +0.045 10 M. Baldwin 9433.598 +50,078 +0.043 10 M. Baldwin 9434.552 +50,081 +0.035 11 R. Monske 9435.686 +50,084.5 +0.047 12 M. Baldwin 9436.643 +50,087.5 +0.042 12 R. Monske 9436.646 +50,087.5 +0.045 12 M. Baldwin 9445.623: +50,115.5 +0.042 21 F. Chapman 9449.630 +50,128 +0.040 20 F. Chapman VX Lacertae 9363.794 + 4,783 -0.024 13 D. Williams Delta Librae 9320.701 + 2,090 -0.009 12 M. Baldwin RT Persei 9435.683 + 7,355 -0.015 13 M. Baldwin J. D. hel E O-C n Observer (2430000) IK Persei \10/ 9125.411 \11/ +17,348 +0.009 -- M. Baldwin 9125.744 \11/ +17,348.5 +0.004 -- M. Baldwin Beta Persei \12/ 9436.635 +513 -0.003 21 R. Monske 9479.642 +528 -0.008 12 J. Olivarez U Sagittae 9337.698: +6,569 +0.001 30 R. Monske V 505 Sagittarii 9319.664 +4,907 -0.016 11 M. Baldwin BV 312 Tauri \13/ 9169.664 +6,579 +0.001 19 M. Baldwin X Trianguli 7220.509 +2,599 +0.016 9 J. Ashbrook 7552.769 +2,941 +0.013 21 J. Ashbrook 9431.721 +4,875 +0.030 14 T. Cragg 9432.691 +4,876 +0.028 10 M. Baldwin 9433.662 +4,877 +0.028 15 M. Baldwin 9434.632 +4,878 +0.026 18 R. Monske 9435.606 +4,879 +0.029 15 M. Baldwin 9436.576 +4,880 +0.027 16 M. Baldwin 9436.578 +4,880 +0.029 15 R. Monske AW Vulpeculae 9376.600 +15,954 -0.010 13 R. Monske BU Vulpeculae 9384.643 +10,170 +0.052 20 R. Monske 1). Normal times of minima from observations between JD 38967 and 39024. O-C's were computed from elements given in IBVS No. 89. 2). O-C computed from elements given in IBVS No. 92. 3). Reduced with a mean light curve. 4). Observations in yellow light: 1P21 + GG 7. Depth of minimum about 0.11 magnitude. Reduced by Kwee-van Woerden method, giving a probable error of + 0.001d. 5). Reduced with a mean light curve. 6). O-C's computed from elements given in IBVS No. 85. Minima by Ruiz reduced by Kwee-van Woerden methods; those of Stokes by the tracing-paper method. 7). Normal times of minima from 119 observations between JD 38931 and 39063. 8). Elements for apsidal motion were used in computing O-C's. 9). O-C's were computed from the elements in Sky and Tele., May, 1963, page 277. 10). O-C's computed from elements given in MVS, 407-8. 11). Normal times of minima from 320 observations between JD 39045 and 39204. 12). O-C's computed from elements given in Sky and Tele., 27, 5, 316. 13). O-C computed from elements in Sky and Tele., 26, 5, 264. 14). O-C computed from 1960 supplement to GCVS. This work is sponsored by the American Association of Variable Star Observers, with David B. Williams as program coordinator. The reductions were made by the writer with Joseph Ashbrook, except in some cases which were checked. L. J. ROBINSON " Sky and Telescope " 49 Bay State Rd. Cambridge, Mass. USA