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Commission 27 of the Iau Information Bulletin COMMISSION 27 OF THE I.A.U. INFORMATION BULLETIN ON VARIABLE STARS Nos. 3501 - 3600 1990 August - 1991 May EDITORS: L. Szabados and K. Olah KONKOLY OBSERVATORY H-1525 BUDAPEST P.O. Box 67, HUNGARY HU ISSN 0374 - 0676 CONTENTS 3501 HD 90892: A NEW VARIABLE IN HYDRA E.M. Halbedel 8 August 1990 3502 HD 97305: A NEW VARIABLE IN LEO E.M. Halbedel 8 August 1990 3503 SOME NON-VARIABLE STARS E.M. Halbedel 8 August 1990 3504 THE IRAS SOURCE 04430-2356 = NSV 1710 IS A MIRA STAR W. Wenzel 10 August 1990 3505 THE POSITION OF RZ NORMAE L.A. Milone 16 August 1990 3506 HD 196470 - A NEW EQUATORIAL RAPIDLY OSCILLATING Ap STAR P. Martinez, D.W. Kurtz, G. Kauffmann, A.C. Jonson 21 August 1990 3507 THE DISCOVERY OF RAPID OSCILLATIONS IN THE Ap STAR HD 161459 P. Martinez, G. Kauffmann 21 August 1990 3508 THE ULTRAVIOLET SPECTRUM OF CLOSE BINARY STAR V448 CYGNI G.V. Volkova 21 August 1990 3509 TWO NEW SOUTHERN RAPIDLY OSCILLATING Ap STARS - HD 193756 AND HD 218495 P. Martinez, D.W. Kurtz 27 August 1990 3510 HD 190290 - ASTEROSEISMOLOGY IN ONE NIGHT P. Martinez, D.W. Kurtz 27 August 1990 3511 UNEXPLAINED LIGHT VARIATIONS OF THE F0 V STAR 9 AURIGAE K. Krisciunas, E. Guinan 31 August 1990 3512 V759 CENTAURI: NEW TIMES OF MINIMA AND REVISED PERIOD R.F. Sistero, B.A. Candellero, S. Marton, A. Grieco 31 August 1990 3513 THE CATACLYSMIC BINARY MV LYRAE RE-ATTAINED ITS UPPER LEVEL B. Fuhrmann, W. Wenzel 5 September 1990 3514 PHOTOMETRY OF THE NEW ECLIPSING BINARY DHK 16 = SAO 80992 D.B. Williams, M.E. Baldwin, D.H. Kaiser 5 September 1990 3515 SEARCH FOR SLOW LIGHT VARIATIONS OF RED DWARF STARS. II. N.I. Bondar' 10 September 1990 3516 ARE THE ALGOL-TYPE STARS V438 CENTAURI, V1156 CYGNI AND V929 OPHIUCHI SURROUNDED BY ACCRETION DISCS? - A CALL FOR OBSERVATIONS C. Friedemann, M. Lowe 12 September 1990 3517 ON THE AMPLITUDE OF THE RECURRENT NOVA V3890 Sgr W. Wenzel 12 September 1990 3518 THE CHANGING LIGHT CURVE OF THE Ap STAR 41 TAURI L. Mantegazza, E. Poretti, E. Riboni 14 September 1990 3519 UNUSUAL PHOTOMETRIC CHARACTER OF THE S-CEPHEID FF Aql I.A. Usenko 17 September 1990 3520 HD 12932, A NEW RAPIDLY OSCILLATING CP2 STAR H. Schneider, W.W. Weiss 28 September 1990 3521 A PERIOD ANALYSIS OF THE SEMI-REGULAR VARIABLE SW Vir J.E. Armour, G.W. Henry, S.L. Baliunas 1 October 1990 3522 QUIESCENT LIGHT VARIATION OF UV Per T. Kato 1 October 1990 3523 B, V, R, I LIGHT CURVES OF V743 SAGITTARII AND ERRATA FOR EH HYDRAE R.G. Samec, J.R. Dewitt 5 October 1990 3524 PHOTOELECTRIC PHOTOMETRY OF TZ BOOTIS D. Schaub 9 October 1990 3525 VARIABILITY OF TWO SUPERGIANTS: HD 3940 AND HD 10494 E. Zsoldos 10 October 1990 3526 UX ANTLIAE, UW CENTAURI AND RZ NORMAE AT MINIMUM BRIGHTNESS L.A. Milone, E.R. Minniti, S. Paolantonio 15 October 1990 3527 NEW PHOTOELECTRIC MINIMA TIMES OF TZ DRACONIS AND ITS PERIOD STUDY H. Rovithis-Livaniou, P. Rovithis 16 October 1990 3528 PHOTOELECTRIC MINIMA TIMES OF GK CEPHEI AND VARIATIONS IN ITS PERIOD H. Rovithis-Livaniou, P.G. Niarchos, P. Rovithis, A. Kalimeris 16 October 1990 3529 PHOTOMETRIC PERIODICITY OF V404 Cyg (= GS 2023+338) T. Kato, R. Hirata 24 October 1990 3530 THE 70th NAME-LIST OF VARIABLE STARS E.V. Kazarovets, N.N. Samus 24 October 1990 3531 A NEW, APPARENTLY UNUSUAL DELTA SCUTI STAR, HD 18878 M.S. Frolov, A.V. Kusakin, A.V. Mironov, V.G. Moshkalev 24 October 1990 3532 ON THE NATURE OF THE CATACLYSMIC VARIABLE V426 OPHIUCHI W. Wenzel, E. Splittgerber 29 October 1990 3533 DIFFERENTIAL PHOTOELECTRIC PHOTOMETRY OF THE DELTA SCUTI STAR AV CETI S.F. Gonzalez-Bedolla, A. Rolland, E. Rodriguez, P. Lopez de Coca 29 October 1990 3534 FIRST SYNTHETIC SOLUTION FOR THE W UMa SYSTEM PP Lac A. Gaspani 31 October 1990 3535 1990 BVR PHOTOMETRY OF XY UMa M. Zeilik, C. de Blasi, S. Gordon, M. Ledlow 31 October 1990 3536 THE X-RAY SOURCE HD 197010 IS AN ECLIPSING BINARY R.M. Robb, F.W. Dean, C.D. Scarfe 1 November 1990 3537 PHOTOELECTRIC OBSERVATIONS OF THE ALGOL-TYPE BINARY STAR RZ Oph S. Zola 1 November 1990 3538 VARIABILITY OF THE DEPTH OF THE MINIMA OF THE DOUBLE SYSTEM HD 135421 A. Dapergolas, E. Kontizas, M. Kontizas 6 November 1990 3539 AN INDEPENDENT CONFIRMATION OF RAPID OSCILLATIONS IN THE COOL Ap STAR HD 12932 T.J. Kreidl 8 November 1990 3540 AW UMa IS IN ACTIVE PHASE OF MASS TRANSFER E. Derman, O. Demircan, Z. Muyesseroglu 12 November 1990 3541 1990 OPTICAL ELLIPTICAL POLARIMETRY AND CENTIMETER FLUX OBSERVATIONS OF THE VERY ACTIVE SOLAR-TYPE STAR HD 129333 N.M. Elias II, J.D. Dorren 13 November 1990 3542 HD 20629: AN X-RAY SELECTED OPTICALLY VARIABLE Ap STAR G. Cutispoto, G. Tagliaferri, F.A. Catalano 16 November 1990 3543 THE DISCOVERIES OF V154 IN M3 W.P. Bidelman 21 November 1990 3544 BV LIGHT CURVES AND THE FIRST EPHEMERIS FOR THE ECLIPSING BINARY STAR NSV 1776 G. Boistel, R. Boninsegna, M. Dumont 21 November 1990 3545 NO "CHROMOSPHERIC ACTIVITY" SEEN IN Eta And K.G. Strassmeier, J. Hron 28 November 1990 3546 "NOVA" PQ And - FURTHER OUTBURSTS G.A. Richter 5 December 1990 3547 THE X-RAY SOURCE 1E1615.0+3114 IS AN ECLIPSING BINARY R.M. Robb, F.W. Dean, C.D. Scarfe 5 December 1990 3548 PHOTOMETRY OF CAPELLA (Dec 1981 TO Apr 1990) K. Krisciunas, E. Guinan 6 December 1990 3549 uvby OBSERVATIONS OF THE ALGOL-TYPE STAR V1156 CYGNI C. Friedemann, H.-G. Reimann 2 January 1991 3550 SIMULTANEOUS TWO-COLOUR OBSERVATION OF THE FLARE STAR EV Lac IN AUGUST 1990 A. Karapetian, V. Zalinian 2 January 1991 3551 1987-1989 UBV PHOTOMETRY OF OO AQUILAE O. Demircan, E. Derman, F. Ekmekci 4 January 1991 3552 TIMES OF MINIMUM LIGHT FOR 17 ECLIPSES OF 7 DETACHED BINARIES D.B. Caton, W.C. Burns, R.L. Hawkins 7 January 1991 3553 DISCOVERY OF RAPID OSCILLATIONS IN HD 19918 P. Martinez, D.W. Kurtz 10 January 1991 3554 FIRST PHOTOELECTRIC LIGHTCURVES IN TWO COLORS AND IMPROVED ELEMENTS FOR V482 Per AND V651 Cas F. Agerer, D. Lichtenknecker 16 January 1991 3555 PHOTOELECTRIC LIGHT CURVE IN TWO COLOURS AND IMPROVED ELEMENTS FOR V724 AQUILAE F. Agerer, D. Lichtenknecker 16 January 1991 3556 CG CYGNI REDUX: MORE 1989 BVR DATA D. Beckert, S. Gordon, E. Jaderlund, E. Mann, M. Zeilik 17 January 1991 3557 MISCLASSIFIED RV TAURI STARS E. Zsoldos 18 January 1991 3558 SPORADIC PHOTOMETRY OF PLEIONE J.D. Fernie 28 January 1991 3559 A NEW FORECAST FOR HS HERCULIS I. Todoran 4 February 1991 3560 BINARY SYSTEM 44i BOOTIS G. Oprescu, M.D. Suran, N. Popescu 4 February 1991 3561 SPECTROSCOPIC OBSERVATIONS OF FIVE F SUPERGIANT STARS S. Tamura, M. Takeuti 11 February 1991 3562 ON THE DELTA SCUTI PERIOD-LUMINOSITY RELATION J.R. King 11 February 1991 3563 THE LONG-TERM BEHAVIOUR OF MWC 560 R. Luthardt 14 February 1991 3564 LIGHT CURVES FOR AB DORADUS T. Banks 15 February 1991 3565 ON SOME MISTAKES IN THE 4th EDITION OF THE GCVS E.V. Kazarovets 20 February 1991 3566 ON TWO POSSIBLE GROUPS OF PULSATING BLUE STRAGGLERS WITH DIFFERENT MASSES IN GLOBULAR CLUSTERS M.S. Frolov 20 February 1991 3567 FLICKERING IN CATACLYSMIC VARIABLES WITH BRIGHT ACCRETION DISKS A. Bruch 25 February 1991 3568 NATURE OF VARIABILITY OF VV Scl P. Renson 1 March 1991 3569 RECENT MINIMA AND IMPROVED EPHEMERIDES FOR THE ECLIPSING HOT SUBDWARFS LB 3459 (= AA Dor) AND BD -7d3477 (= HW Vir) D. Kilkenny, M. Harrop-Allin, F. Marang 7 March 1991 3570 1988 AND 1989 PHOTOMETRY OF UZ LIBRAE P.A. Heckert, M.A. Hickman 8 March 1991 3571 WR 22 IS AN ECLIPSING BINARY STAR E. Gosset, M. Remy, J. Manfroid, J.-M. Vreux, C. Sterken, L.A. Balona, G.A.P. Franco 8 March 1991 3572 ANALYSIS OF X-RAY ECLIPSES IN SS 433 E.A. Antokhina, A.M. Cherepashchuk, E.V. Seyfina 8 March 1991 3573 NEW VARIABLE STARS IN THE FIELD OF IC 1805 V. Gasperoni, P. Maffei, G. Tosti 11 March 1991 3574 V1963 Sgr - A NEW W UMa TYPE STAR P. Maffei, G. Tosti 11 March 1991 3575 PHOTOELECTRIC OBSERVATION OF VW CEPHEI IN R AND IR K. Arai 12 March 1991 3576 A VERY INTERESTING VARIABLE V627 Cas (AS 501): BRIGHTENING FORECAST FOR MID-1991 E.A. Kolotilov, A.S. Miroshnichenko, B.F. Yudin 12 March 1991 3577 SIMULTANEOUS PHOTOELECTRIC OBSERVATIONS OF AD LEONIS A.P. Antov, V.V. Genkov, R. Konstantinova-Antova, N.K. Kirov 14 March 1991 3578 CCD PHOTOMETRY OF BX PEGASI IN 1990 J.A. DeYoung, R.E. Schmidt, L.I. Gritz 15 March 1991 3579 A NEW ECLIPSING VARIABLE IN THE BX PEGASI FIELD J.A. DeYoung 15 March 1991 3580 THE PHOTOELECTRIC PHOTOMETRY OF THE SUSPECTED VARIABLE PG 0900+401 N.A. Lipunova, S.Yu. Shugarov 20 March 1991 3581 OBSERVATIONS OF SUPERNOVA 1989 B I.M. Volkov 20 March 1991 3582 IS BN Ori STARTING AGAIN? G.U. Kovalchuck 22 March 1991 3583 UBV PHOTOMETRY OF THE SYMBIOTIC STAR V1329 Cyg IN 1989-1990 A. Dapergolas, E. Kontizas, M. Kontizas 22 March 1991 3584 LIGHT-CHANGES OF THE CENTRAL STAR OF PLANETARY NEBULA NGC 2346 IN JANUARY 1991 L. Kohoutek 22 March 1991 3585 HD 50138: PHOTOMETRIC BEHAVIOUR CONNECTED WITH ITS RECENT SHELL EPISODE E.M. Halbedel 4 April 1991 3586 PHOTOMETRY OF TWO CANDIDATES FOR M67 CONTACT BINARIES J.
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