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IAUC 5312: 1991am; 1991al; AM Her; 1991t

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                                                  Circular No. 5312
Central Bureau for Astronomical Telegrams
Postal Address: Central Bureau for Astronomical Telegrams
Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
Telephone 617-495-7244/7440/7444 (for emergency use only)
TWX 710-320-6842 ASTROGRAM CAM     EASYLINK 62794505

SUPERNOVA 1991am IN MCG +06-37-006
     C. Pollas, Observatoire de la Cote d'Azur, reports his discovery,
on a technical pan film (limiting mag 21.5) taken on July 14.92
UT by D. Albanese, of an apparent supernova of mag 19.0 located in
MCG +06-37-006 at R.A. = 16h40m05s.67, Decl. = +37 49'49".6 (equinox
1950.0).  A July 24.90 red exposure (limiting mag 20) by Pollas
shows the object at R about 19.  The host galaxy is a face-on spiral
galaxy (mag 16) with center at R.A. = 16h40m05s.36, Decl. =
+37 49'43".5; a nearby star of mag 15 is at R.A. = 16h40m01s.10,
Decl. = +37 50'25".7.  Nothing is present on the POSS prints to B =
21 and R = 20.

     P. Bouchet, M. Della Valle, and J. Melnick, European Southern
Observatory, report: "Preliminary inspection of a low-resolution CCD
spectrum (360-870 nm) of SN 1991al (cf. IAUC 5310), obtained on July
21.38 UT with the ESO New Technology Telescope at La Silla, yields
P-Cyg profiles for Balmer lines and Na I (587 nm) and indicates that
this is a type-II supernova.  The expansion velocity, corresponding
to the difference between the rest wavelength in the galaxy's frame
and the minimum of the absorption, is about 8000-9000 km/s.  The
redshift of the host galaxy, determined from the H-alpha emission,
is z = 0.01."

     W. Goetz and K. Heiland, Sonneberg Observatory, report that
observations in B on July 16, 19, and 20 show this variable in its low
state again.  Visual magnitude estimates (cf. IAUC 5254):  Apr.
21.44 UT, 13.1 (P. Sventek, Houston, TX); May 5.02, 13.1 (S. Korth,
Dusseldorf, Germany); 20.08, 13.3 (M. Verdenet, Bourbon-Lancy,
France); 22.07, 14.0 (Verdenet); June 4.91, 14.0 (Korth);
9.84, 13.3 (A. Boattini, Florence, Italy); 30.84, 14.0 (Boattini);
July 4.94, 14.2 (Korth).

     Total visual magnitude estimates:  July 15.43 UT, 9.4 (C. S.
Morris, Pine Mountain Club, CA, 20x80 binoculars); 16.42, 10.2 (A.
Hale, Las Cruces, NM, 0.41-m reflector); 21.99, 10.8 (J. Jahn,
Bodenteich, Germany, 0.20-m reflector); 24.08, 10.4 (H. Mikuz, Cres,
Yugoslavia, 0.20-m reflector).

1991 July 25                   (5312)             Daniel W. E. Green

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