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IAUC 4489: N Vul 1987; RV And; V818 Sco

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IAUC number 

                                                  Circular No. 4489
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
Postal Address: Central Bureau for Astronomical Telegrams
Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
TWX 710-320-6842 ASTROGRAM CAM    Telephone 617-495-7244/7440/7444


NOVA VULPECULAE 1987
     E. Horine, M. Garcia, and R. Schild, Smithsonian Astrophysical
Observatory, report:  "Photometric and spectroscopic observations
made at Whipple Observatory confirm that the object discovered by
Beckmann and Collins (IAUC 4488) is a nova.  We estimate a position
from telescope encoders of R.A. = 19h04m09s, Decl. = +21 44'24" (equinox
1987.8).  A spectrogram (range 450-700 nm, 1.0-nm resolution) taken
on Nov. 16.13 UT suggests a K1 absorption spectrum with strong H-alpha
emission (FWZI about 2.0 nm in width) in a P-Cyg profile.  The H-beta and
higher lines are seen in absorption.  No other emission lines are
evident in the spectrum.  From preliminary reduction of CCD BVRI
data we infer magnitude V = 7.1 at Nov. 16.156."
     Photoelectric photometry by R. Zissell, Mount Holyoke College:
Nov. 16.99 UT, V = 7.78, B-V = +1.18 (+/- 0.03); comparison stars
1 Vul (V = 4.77, B-V = -0.04) and 13 Her (V = 4.59, B-V = +0.78).
     R. H. McNaught, Siding Spring Observatory, reports that a
photograph taken Oct. 26.44 UT shows no object brighter than mag 11.5
at the location of the nova.


RV ANDROMEDAE
     R. Cadmus, Department of Physics, Grinnell College, writes:
"The character of the lightcurve of the semiregular variable RV And
has changed dramatically.  Photoelectric photometry with the 0.61-m
telescope at Grinnell College suggests that the amplitude in V is
now increasing after dropping to a few tenths of a magnitude (the
'normal' amplitude is about 2 mag) and the period is now about 57 days
(the 'normal' period is about 172 days)."


V818 SCORPII
     G. Hasinger, Max Planck Institute for Extraterrestrial Physics,
Garching, and M. van der Klis, EXOSAT Observatory, European
Space Agency, write:  "An analysis of 5- to 35-keV data on V818 Sco
(Sco X-1) obtained with EXOSAT on 1986 Mar. 11-14 (time resolution
0.98 ms) does not confirm the presence of pulsations near 341 Hz
(IAUC 4485).  Averaging 16 900 fast Fourier transforms of 8-s
exposures each, we obtain a 99-percent confidence upper limit on the
fractional amplitude of pulsations of 0.004 (range 338-344 Hz)."


1987 November 17               (4489)            Daniel W. E. Green

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