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IAUC 6450: 4U 0115+634; N Sgr 1996; PERSEID METEORS 1996

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                                                  Circular No. 6450
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)

4U 0115+634
     M. Scott and M. H. Finger, Universities Space Research
Association; R. B. Wilson, Marshall Space Flight Center, NASA; and
T. A. Prince and B. Vaughan, California Institute of Technology,
report for the Compton GRO Observatory BATSE pulsar team: "Pulsed
hard x-ray flux is currently being detected from the transient
Be/x-ray pulsar 4U 0115+634.  The source was detected on Aug. 10,
when the rms pulsed flux (20-50 keV) was approximately 25 mCrab.
This is the first detection by BATSE of this source since a pair of
outbursts that occurred during the interval 1995 Nov. 18-1996 Jan.
9 (IAUC 6266).  On 1996 Aug. 12, the rms pulsed flux (20-50 keV)
was approximately 30 mCrab.  The pulse frequencies observed from
Aug. 10 to 12 are consistent with a neutron-star spin rate of
0.27666712 +/- 0.00000022 Hz and no detectable spin-up, using the
binary orbital ephemeris of Rappaport et al. (1978, Ap.J. 211, L1)
with the epoch of periastron passage updated to 1996 Aug. 5.5 UT."

     L. V. Morrison and R. W. Argyle, Royal Greenwich Observatory,
report an accurate optical position for N Sgr 1996, from nine
observations obtained with the Carlsberg Automatic Meridian Circle
on La Palma and operated by C. Fabricius and L. V. Morrison: R.A. =
18h23m42s.501, +/- 0s.005, Decl. = -18o07'14".80 +/- 0".07 (equinox
J2000.0, FK5 reference frame, epoch 1996.61).  The following V
magnitudes have also been measured (+/-0.08 mag):  Aug. 5.94 UT,
11.01; 6.94, 11.20; 7.94, 11.54; 8.93, 11.65; 9.93, 11.96; 10.93,
12.29; 11.92, 12.07; 12.92, 12.19; 13.92, 12.15.
     E. Martin, Instituto de Astrofisica de Canarias, reports the
following near-infrared magnitudes obtained with the 1.5-m Carlos
Sanchez telescope (+ CVF photometer) at Teide Observatory on  Aug.
9.965 (heliocentric) UT:  J = 8.93 +/- 0.04, H = 8.73 +/- 0.03, K =
8.35 +/- 0.03.

     A. Kereszturi, K. Sarneczky, and I. Tepliczky, Hungarian
Astronomical Association; and P. Jenniskens, NASA Ames Research
Center, report that observations from Europe suggest that the peak
in 1996 Perseid activity occurred around Aug. 12.06 UT, at up to
two or three times the normal rates.  C. M. Gaskell, University of
Nebraska, writes that the mean Perseid magnitude on Aug. 12 was
almost two mag brighter than historic means.

                      (C) Copyright 1996 CBAT
1996 August 14                 (6450)            Daniel W. E. Green

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