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IAUC 6368: 1987A; GRO J1744-28; 65P

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                                                  Circular No. 6368
Central Bureau for Astronomical Telegrams
Postal Address: Central Bureau for Astronomical Telegrams
Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions)
Phone 617-495-7244/7440/7444 (for emergency use only)

     P. Garnavich and R. Kirshner report, on behalf of the
Supernova INtensive Study (SINS) collaboration:  "Hubble Space
Telescope images of SN 1987A show that the [N II] 658.4-nm flux
from a segment of the inner circumstellar ring increased by 15
percent between 1994 Oct. and 1996 Feb.  The ring segment is
centered at p.a. 206o and subtends about 35o.  The remainder of the
ring has faded by 5 to 10 percent in [N II].  No unusual activity
is seen the [O III] 500.7-nm emission, and the entire ring faded by
an average of 10 percent.  The flux increase could be the first
indication of the predicted interaction between the supernova
ejecta and the circumstellar gas.  Observations at radio and x-ray
wavelengths may show considerable changes if the interaction has
begun.  However, since the optical activity is detected only in [N
II] and is on the south side (thought to be the far side) of the
ring, it is unlikely to be the onset of the collision.  Models by
Lundqvist and Fransson (1996, Ap.J., in press) imply that [N II]
emission would continue to increase beyond day 2000 if the ring
segment consisted of very-low-density gas."

GRO J1744-28
     T. Dotani, Y. Ueda, F. Nagase, and H. Inoue, Institute of
Space and Astronautical Science; and C. Kouveliotou, Universities
Space Research Association and Marshall Space Flight Center, NASA,
communicate:  "Further analysis of ASCA data of GRO J1744-28
obtained between Feb. 26.42 and 27.09 UT yields the source position
at R.A. = 17h44m31s.5, Decl. = -28o44'26" (equinox 2000.0), with a
90-percent-confidence error radius of 1'.  The source position was
also cross-checked with reference to the Einstein source 2E
1743.1-2842, which was detected in the same field of view.  The
result is fully consistent with the above coordinates, taking into
account the IPC error radius of 51" for 2E 1743.1-2842.  The ASCA
error circle overlaps the XTE error region (IAUC 6309), but the VLA
radio source (IAUC 6323) lies slightly outside the ASCA error

     Visual m1 estimates:  Feb. 19.51 UT, 13.6 (A. Hale,
Cloudcroft, NM, 0.41-m reflector); 25.10, 13.6 (K. Sarneczky,
Raktanya, Hungary, 0.44-m reflector); Mar. 17.48, 13.3 (Hale);
26.45, 13.4 (Hale); 28.07, 13.4 (K. Hornoch, Lelekovice, Czech
Republic, 0.35-m reflector).

                      (C) Copyright 1996 CBAT
1996 April 1                   (6368)            Daniel W. E. Green

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