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IAUC 6632: GRB 970402 AND BL Cir; 1997bs; X2127+119

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                                                 Circular No. 6632
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
Mailstop 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions)
BMARSDEN@CFA.HARVARD.EDU or DGREEN@CFA.HARVARD.EDU (science)
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Phone 617-495-7244/7440/7444 (for emergency use only)


GRB 970402 AND BL CIRCINI
     T. E. Harrison, B. J. McNamara, and P. A. Mason, New Mexico
State University (NMSU), for the BATSE/COMPTEL/NMSU Rapid Response
Network (McNamara et al. 1996, Ap.J. Supp. 103, 173), report:  "We
have examined a U.K. Schmidt Telescope (UKST) plate obtained on Apr.
3.73 UT by F. G. Wilson (Anglo-Australian Observatory) at the
position of the reported BeppoSAX x-ray counterpart for GRB 970402
(IAUC 6617).  No sources within the error circle appear to have
exhibited significant changes in brightness when compared to the
ESO Survey plates.  We confirm the observations (IAUC 6628) that BL
Cir is very faint.  On the new UKST plate, with a bandpass centered
at 590 nm, BL Cir is at V about 20.  On the ESO blue and red plates,
BL Cir is within its 'normal' brightness range of m_pg about 15-16.
BL Cir has been classified as a long-period variable (Hoffmeister
1965, A.N. 289, 1).  The dramatic fading, along with the G-K
spectral type suggest that BL Cir may be a previously unknown R CrB
star.  Follow-up infrared observations would be useful in
confirming this hypothesis."


SUPERNOVA 1997bs IN NGC 3627
     M. Cavagna reports the following precise position for SN
1997bs, obtained at Sormano with the 0.5-m reflector + CCD by F.
Manca and himself on Apr. 17.850 UT:  R.A. = 11h20m14s.25, Decl. =
+12o58'19".6 (equinox 2000.0).


X2127+119
     R. Corbet, Goddard Space Flight Center (GSFC) and Universities
Space Research Association; A. Peele, GSFC and National Research
Council; and D. A. Smith, Massachusetts Institute of Technology
(MIT), report on behalf of the RXTE ASM team at GSFC/MIT:
"Observations of this low-mass x-ray binary in M15, obtained
between 1996 Jan. 1 and 1997 Apr. 10 with the ASM on RXTE, show (in
addition to considerable non-periodic variability) the presence of
a modulation with a period of 37 days about the average 2-12-keV
flux of 15 mCrab.  This modulation is most prominent in the lowest
energy band (1.3-3.0 keV) at an average level of about 35 percent
and a FWHM in the Fourier transform of about 3.5 days, but is
undetectable in the highest energy band (4.8-12 keV).  Maximum
brightness occurs at an epoch of about 1996 May 25.  Modulation at
the 17.1123-hr orbital period is also seen.  We encourage continued
observations at x-ray and optical wavebands to search for other
manifestations of the 37-day period and to determine whether this
is a persistent property of X2127+119."

                      (C) Copyright 1997 CBAT
1997 April 19                  (6632)            Daniel W. E. Green

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