Central Bureau for Astronomical Telegrams
IAUC 4635: GX 1+4; 1988P; SU UMa; 3C 279
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Read IAUC 4636
Circular No. 4635
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
Postal Address: Central Bureau for Astronomical Telegrams
Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
TWX 710-320-6842 ASTROGRAM CAM Telephone 617-495-7244/7440/7444
MARSDEN or GREEN@CFA.BITNET MARSDEN or GREEN@CFAPS2.SPAN
GX 1+4
E. Gotthelf, J. Halpern, and A. Szentgyorgyi, Columbia
University, write: "An optical spectrum of the x-ray pulsar GX 1+4
obtained using a grism/CCD spectrograph on the Shane 3-m telescope
at Lick Observatory on July 8 UT by R. Becker and D. Helfand
suggests a change in activity of this system. Comparison with
published spectra (Davidsen et al. 1977, Ap.J. 211, 866) reveals
an absence of previously observed high-excitation forbidden lines.
In particular, the [Fe VII] 608.7-nm line is at least 6 times weaker
than previously reported and the [Fe VII] 572.1-nm, [Fe X] 637.4-nm,
and [O III] 495.9- and 500.7-nm lines are undetected, while the strong
H-alpha and the He I 587.6-, 667.8-, and 706.5-nm lines remain at their
previously reported flux levels to within 15 percent. We speculate
that the absence of the high-excitation lines is correlated with
the low x-ray state as reported by Makishima et al. (1988, Nature
333, 746)."
SUPERNOVA 1988P IN ANONYMOUS GALAXY
C. Pollas, Observatoire de la Cote d'Azur, writes concerning
the report by Filippenko and Schachter (IAUC 4630): "Palomar Sky
Survey prints show a faint, diffuse, probable H II region at
approximately the same position as the probable supernova 1988P,
at mag ~ 20-21 on the blue print (~ 20 on the red print). Our
June 9 (IIIa-J) and 14 (IIa-O) plates show the SN candidate to be
significantly (> 2 mag) brighter than this. On June 18.96 UT, C.
Buil and E. Thouvenot found SN 1988P at mag 19-19.2 (0.6-m telescope
+ unfiltered CCD, Pic du Midi Observatory)."
SU URSAE MAJORIS
P. Schmeer, Bischmisheim, West Germany, telexes that this object
is undergoing an outburst typical of a supermaximum, as indicated
by the following visual magnitude estimates: July 25.96 UT, [12.7;
30.98, 11.9; 31.96, 11.5; Aug. 1.09, 11.6; 4.10, 11.5.
3C 279
A. C. Sadun, Agnes Scott College, reports the following
magnitudes: May 24 UT, V = 13.58 (0.6-m telescope, Capilla Peak
Observatory, University of New Mexico); May 25.169, V = 11.51 (Capilla
Peak); June 16, V = 13.6, B-V = +0.5 (Table Mountain Observatory
0.6-m telescope).
1988 August 6 (4635) Daniel W. E. Green
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