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IAUC 4492: N Vul 1987; PSR 1951+32; 1986k; 1987p

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IAUC number 

                                                  Circular No. 4492
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
     H. Kosai, Tokyo Astronomical Observatory, reports that Yukio
Sakurai, Mito, Ibaraki prefecture, independently discovered the
nova on Fujicolor HR1600 film exposed Nov. 16.416 UT, mag = 8.0.
     Visual magnitude estimates:  Nov. 17.122 UT, 7.8 (P. Collins,
Scottsdale, AZ); 17.151, 7.8 (Collins); 18.08, 7.2 (A. Hale, Las
Cruces, NM); 18.78, 7.3 (A. Pereira, Linda-A-Velha, Portugal);
19.056, 7.2 (Collins); 19.160, 7.4 (Collins).


PSR 1951+32
     J. D. Li, T. P. Li, Y. Q. Ma, and M. Wu, High-Energy Astrophysics
Laboratory, Academia Sinica, Beijing, write:  "The radio pulsar
PSR 1951+32 is placed within the field-of-view of COS-B observation
No. 26 taken in 1977 Nov.  We performed a folding-algorithm
search for periodicity of 50- to 5000-MeV gamma-rays coming from the
pulsar's direction in the COS-B data.  The search region for the
period (P) and period derivative (P-dot) is  0.0395277-0.0395280 s  and
5.6-6.3 x 10E-15 s/s, respectively, selected on the basis of the
pulsar parameters measured at radio wavelengths in 1987 July (IAUC
4426).  Statistically significant evidence of pulsation structure
in phase distribution of 378 gamma-ray photons was obtained at P =
0.03952789558 +/- 0.00000000012 s, P-dot = 6.0 (+/- 0.1) x 10E-15 s/s (epoch
1977 Nov. 1.38 UT) with maximum chi-square = 82.4 (19 degrees of freedom).
Similar positive indications of a 39-ms period have also been
obtained from the other COS-B data in which the pulsar was within the
field-of-view (e.g., observations No. 4 of 1975 Nov.-Dec. and No.
55 of 1980 Oct.)."


PERIODIC COMET KOHOUTEK (1986k)
     Total visual magnitude estimates:  Oct. 29.21 UT, 12.9 (J. D.
Shanklin, Cambridge Observatories, 0.33-m reflector); Nov. 17.42,
13.6 (A. Hale, Las Cruces, NM, 0.41-m reflector).


PERIODIC COMET BORRELLY (1987p)
     Total visual magnitude estimates:  Oct. 27.53 UT, 8.7 (D. A.
J. Seargent, The Entrance, N.S.W., 15x80 binoculars); Nov. 10.25,
9.0 (Hale); 15.96, 8.0 (A. Boattini, Piazzano, Italy, 0.40-m refl.;
8' tail); 19.22, 7.7 (J. Scotti, Kitt Peak, AZ, 10x50 binoculars).


1987 November 19               (4492)            Daniel W. E. Green

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