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IAUC 5993: N Sgr 1994 No. 2; Mkn 421; 1993a

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                                                  Circular No. 5993
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

     Yukio Sakurai (Mito, Ibaragi, Japan) reports his discovery of
a nova on SG400 patrol films taken with a 300-mm camera lens and
provides the following position:  R.A. = 18h27m28s, Decl. = -17o14'.2
(equinox 1950.0).  Magnitude estimates:  May 16.733 UT, [11.5
(Sakurai); 20.710, 10.8 (Sakurai); 22.603, 11.4 (S. Takahashi, Shiga,
Japan; visual); 22.620, 11.6 (M. Watanabe, Toyama, Japan; visual).
     S. J. Austin, G. Schwarz, and S. Starrfield, Arizona State
University; and R. M. Wagner, Ohio State University, report: "Optical
spectrograms of Nova Sgr 1994 No. 2 were obtained with the Perkins
1.8-m telescope (+ CCD spectrograph) on May 23.3 UT.  The spectra
(range 473-695 nm, resolution 1.2 nm) exhibit permitted emission
lines due to the Balmer series of hydrogen and Fe II (multiplets 37,
38, 42, 48, 49, 55, and 74) superposed on a red continuum.  Many of
the Fe II lines appear to exhibit weak P-Cyg profiles, but these
are much less certain at our resolution.  The profile of H-alpha
exhibits an asymmetry to the red.  The FWHM of H-alpha and H-beta
emission, corrected for instrumental resolution, was about 450 km/s.
The spectra confirm the identification as a nova with an early
post-maximum 'Fe II class' spectrum.  The widths of the emission
lines suggest that the development of this nova will be moderately

     T. Takahashi, M. Tashiro, T. Kamae, and K. Makishima, University
of Tokyo; T. Kii and F. Makino, ISAS; T. Ohashi, F. Takahara, and
N. Y. Yamasaki, Tokyo Metropolitan University; R. Hartman and G.
Madejski, Goddard Space Flight Center, NASA; R. C. Lamb, Iowa State
University; and T. C. Weekes, Whipple Observatory, report:  "The BL-
Lac object Mkn 421 was observed from the x-ray astronomy satellite
ASCA during May 16.4-17.3 UT.  The preliminary energy flux obtained
from the GIS aboard ASCA was very bright, 1.8 x 10E-10 erg cmE-2
sE-1 (2-10 keV), which is about 2 times higher than that observed
by EXOSAT in December 1984 (George et al. 1988, M.N.R.A.S. 232, 793).
The photon index was about 2.5.  Observations at optical, infrared,
radio, and other wavelengths are encouraged."

     Total visual magnitude estimate by A. Hale (near Orogrande, NM,
0.41-m reflector):  May 17.43 UT, 11.3.

1994 May 23                    (5993)            Daniel W. E. Green

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