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IAUC 4331: 1987A; N Her 1987

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                                                  Circular No. 4331
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
     S. Ryan, Mount Stromlo Observatory, telexes: "High signal-to-
noise spectra (range 320-740 nm, resolution 40 km/s) were obtained
on Mar. 3.  The spectrum is still continuum with P-Cyg profiles of
Balmer lines, but seven other broad absorption features have
appeared or strengthened since the Feb. 27 observations of Rodgers
and Harding (IAUC 4328).  The wavelengths in nm of these features
(and tentatively suggested identifications in three cases) are
575.0 (He I 587.6), 504.5, 489.0 (He I 501.6), 479.5 (He I 492.2),
444.0, 363.5 and 347.0.  Since Feb. 27 the absorption coefficients
of the Balmer P-Cyg profiles have deepened and shifted redward by
4 to 8 nm.  On Mar. 3 the H alpha absorption component had FWHM 17 nm,
residual central intensity 25 percent of continuum and central
wavelength 628 nm; the centers of other H absorption features are H beta
469 nm, H gamma 421 nm and H delta 398 nm.  These wavelengths correspond
to velocities 13 400, 10 600, 9400 and 8800 km/s, respectively."
     D. Carter and M. L. Winsall, Mount Stromlo and Siding Spring
Observatories, report: "Spectra taken on Mar. 4.42 UT with the AAT
show the supernova to be of type II.  Hydrogen emission can only
be seen at H-alpha, where the total velocity range of the P-Cyg profile
is -22 000 to +16 800 km/s.  The blueshift (in km/s) of the absorption minima
is 12 600 at H alpha, 9860 at H beta, 8840 at H gamma, 8110 at H delta, 7400
at P delta and 6600 at P epsilon.  The broad P-Cyg feature identified by
Danziger and Fosbury (IAUC 4326) as Ca II covers the range 816-891
nm, the absorption minimum being at 829 nm.  There are broad
absorption features centered at 446, 491, 507, 575 and possibly at
521 and 764 nm.  There is little flux shortward of 380 nm."
     Visual magnitude estimates: Mar. 4.46, 4.4 (G. Garradd,
Tamworth, N.S.W.); 4.53, 4.4 (T. Beresford, Adelaide, S. Australia).


NOVA HERCULIS 1987
     Photometry by R. Monella, Covo, Italy:  Feb. 3.179 UT, V =
7.86, B-V = +0.32, U-B = -0.54; Feb. 6.181, 7.98, +0.46, -0.39;
Feb. 8.180, 8.24, +0.57, -0.76; Feb. 21.178, 9.12, +0.93, +0.32;
Feb. 23.182, 9.29, +1.38, +0.68; Feb. 24.173, 9.36, +1.17, +0.51.
     Visual magnitude estimates by A. Pereira, Linda-A-Velha,
Portugal): Feb. 19.25 UT, 8.8; 22.23, 9.0; Mar. 1.20, 9.3; 2.24, 9.6.


1987 March 5                   (4331)              Brian G. Marsden

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