Circular No. 3201 Central Bureau for Astronomical Telegrams INTERNATIONAL ASTRONOMICAL UNION Postal Address: Central Bureau for Astronomical Telegrams Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A. Cable Address: SATELLITES, NEWYORK Telex: 921428 Telephone: (617) 864-5758 NOVA SERPENTIS 1978 M. K. V. Bappu, Indian Institute of Astrophysics, reports that image-tube spectrograms obtained by T. P. Prabhu with the Kavalur 100-cm telescope during Mar. 10.92-11.01 UT (dispersion 165 A/mm, range 4200-8700 A) and during Mar. 11.95-11.97 UT (86 A/mm, 7200-8700 A) exhibit a principal spectrum. Emission lines of H, Na D, Ca II (multiplet 2), Fe II (multiplets 42 and 49), O I 7772 and 8446 A are very strong. [O I] 6300 and 6363 A, N II 5755 A, Fe II (multiplets 27, 37, 38, 40, 73 and 74), O I 8228 A, Si II 6347 and 6371 A and Mg II 4481 A are moderate. Typical velocity widths are 1600 km/s. H-alpha has a total width of 2650 km/s at zero intensity; the mean absorption velocity is -1240 +/- 60 (p.e.) km/s. On Mar. 19.96 UT the H-alpha profile (dispersion 25 A/mm) shows a sharp edge at -510 km/s. 4U 1538-52 A. Cowley, D. Crampton and J. B. Hutchings, Dominion Astrophysical Observatory, report that spectrograms of candidate star 12 (IAUC 3184, 3197) obtained at Cerro Tololo Interamerican Observatory show radial-velocity variations (K ~ 25 km/s) in the 3.73-day x-ray period in antiphase with the x-ray pulsations (IAUC 3078). This confirms the star as the optical candidate for the source. X PERSEI P. Bernacca and A. Bianchini, Asiago Astrophysical Observatory communicate: "Photoelectric observations were perfomed on X Per from January to March using a two-channel photon-counting photometer with 1-second integration time in the U band. On Mar. 9 and 10 four attenuation features of duration 10 to 30 seconds and depth 0.06 to 0.2 magnitude (6 to 18 percent) were observed. Analysis of the comparison star, which is much fainter than X Per, indicates that the probability of reduced sky transparency being responsible for these features is not larger than 0.3 percent for three of them and not larger than 0.01 percent for the deepest one. These dips are similar to those observed by Campisi et al. (1976, Monthly Notices Roy. Astron. Soc. 176, 225) in U light and by Canizares et al. (preprint) in 4686 A light using a one-channel photometer." 1978 March 24 (3201) Brian G. Marsden
Our Web policy. Index to the CBAT/MPC/ICQ pages.