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IAUC 4405: 1987A; U Sco; NOTICE RE Tlgms

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                                                  Circular No. 4405
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


SUPERNOVA 1987A IN THE LARGE MAGELLANIC CLOUD
     R. K. Sood, J. Thomas, L. Waldron and B. Denehy, Australian
Defence Force Academy, Canberra; G. Rochester and T. Sumner, Imperial
College, London; G. Frye, R. Koga and P. Albats, Case Western
Reserve University, Cleveland; R. Staubert, Astronomisches Institut,
Tubingen; and P. Ubertini and A. Bazzano, Istituto de Astrofisica
Spaziale, Frascati, telex: "SN 1987A was observed during Apr.
19.040-19.299 UT with a combined x-ray detector flown on a stratospheric
balloon from Alice Springs.  The gamma-ray detector consisted
of a multiple optical spark chamber with a sensitive area of 400
cm**2, field of view 60 deg FWHM, energy range 50-500 MeV and time resolution
10 microseconds.  The counting rate profile at 2.0 mb float altitude
yields a 3 sigma upper limit to the steady gamma-ray flux from SN 1987A in
the above energy range of 7 x 10**-4 photons cm-2 s-1.  Complete data
analysis will improve sensitivity by a factor of about 20."
     N. Suntzeff and M. Hamuy, Cerro Tololo Interamerican
Observatory, telex: "Nightly photometric observations in the Cousins'
UBVRI system on the CTIO 0.4-m telescope show that SN 1987A is
fading rapidly.  During June 7-11 it declined in all colors, with
U, B and V fading more rapidly than R and I.  During this time
period V and I dimmed linearly by 0.050 and 0.036 mag/day,
respectively. On June 10.97 UT there were measured V = 3.52, B-V =
+1.72, U-B = +2.50, V-R = +0.85, R-I = +0.35."
     Visual magnitudes: June 8.35, 3.4 (D. Seargent, The Entrance,
N.S.W.); 9.35, 3.4 (Seargent); 10.63, 3.3 (Seargent); 11.46, 3.3
(A. Beresford, Adelaide, South Australia); 12.37, 3.3 (Beresford).


U SCORPII
     Visual magnitudes by R. H. McNaught, Coonabarabran, N.S.W.:
May 29.61 UT, 14.3; 30.68, 14.2:; 31.53, 14.7; June 3.76, 14.7.


NOTICE CONCERNING TELEGRAMS
     It is once again an 'open season' for making changes in the
list of subscribers to the Central Bureau's telegram service.
Subscribers who wish to make address changes, category changes,
etc., are requested to inform us of said changes by July 31.  We
regret that a charge of $50.00 must be made for address changes
and deletions (but not additions) outside these biannual seasons.


1987 June 12                   (4405)              Brian G. Marsden

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