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IAUC 3197: HR 1099; VV Pup; 4U 1630-47; N Oph 1977; 4U 1837+04 AND 4U 1538-52; Var GALAXIES

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IAUC number

                                                  Circular No. 3197
Central Bureau for Astronomical Telegrams
Postal Address: Central Bureau for Astronomical Telegrams
Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
Cable Address: SATELLITES, NEWYORK     Telex: 921428
Telephone: (617) 864-5758

HR 1099
     E. F. Milone, Department of Physics, University of Calgary,
writes that the mean of five differential UBV observations of HR
1099 relative to HR 1101 on Feb. 22.1664 (heliocentric) UT gave Delta-V
= +1.58, Delta-(B-V) = +0.328, Delta-(U-B) = +0.42.  The observations were
made with the Rothney Astrophysical Observatory's 40-cm reflector.

     B. W. Bopp and J. C. Talcott, Ritter Observatory, write that
spectrograms obtained during Feb. 21-23 showed that the equivalent
width of the H-alpha emission was ~ 2.0 A, some 2-3 times greater than
during quiescent intervals.  The emission was significantly broader
than the 1-A instrumental resolution on Feb. 21.  On Feb. 22 there
was some suggestion of variations of ~ 30 percent in the H-alpha
equivalent width on a timescale of ~ 20 min.

     R. Hobbs, Y. Kondo and W. Feibelman, Goddard Space Flight Center,
report that observations (dispersion 40 A/mm) on Feb. 24.05,
26.05 and 28.06 UT showed the H and K lines to exhibit strong
emission cores on each occasion.  Preliminary calibration shows that
the emission was about twice as strong on Feb. 24 as on Feb. 26 and
28.  H-alpha was also in emission, but because of unoptimized exposure
at that wavelength no possible variation could be established.

     J. L. Greenstein and B. Zimmerman, Hale Observatories, write
that they found this magnetic variable to be bright (V estimated at
14.8) on Mar. 15.2 and 16.2 UT, using the SIT digital spectrograph
at the 500-cm reflector.  The continuum is now blue with strong,
broad, H, He I and He II emission lines.  The 4686 A, 4650 A blend is
as strong as H-beta, i.e., the spectrum is of high excitation, and the
object could be an x-ray emitter.  In January and February multichannel
spectrophotometry by Greenstein and J. B. Oke had shown it
faint (V = 17.9), without detectable emission lines, with a flat
spectrum and a late-M dwarf dominating longward of 7500 A.  The
brightening, observed independently, confirms the announcement and
the predictions of Stockman and Angel on IAUC 3187.

4U 1630-47
     G. Share, K. Wood, E. Byram, J. Meekins, S. Shulman and their
collaborators, Naval Research Laboratory; and R. Griffiths, Center
for Astrophysics, report the detection by HEAO 1 of the recurrent
transient 4U 1630-47 during Mar. 2-7.  The measured position was
within 0o.2 of the transient, and the 1-10-keV intensity was ~ 5 x
10**-10 erg cm**-2 s**-1.  The transient's intensity was ~ 5 x 10**-11 erg
cm**-2 s**-1 as measured by A1 in early Sept. 1977 but had flared to
10**-8 erg cm**-2 s**-1 in Nov. 1977 (cf. IAUC 3144).

     L. J. Kaluzienski, E. A. Boldt, S. S. Holt, R. F. Mushotzky,
P. J. Serlemitsos and R. E. Rothschild, Goddard Space Flight Center,
independently report the detection by HEAO A2 of a bright x-ray
source centered on the position of 4U 1630-47.  The flux measured
on Mar. 3d13h was ~ 2 x 10**-9 erg cm**-2 s**-1 (2-10 keV), which is more
than an order of magnitude greater than the upper limit obtained
for 4U 1630-47 during the previous A2 scan of this region conducted
during 1977 Sept. 3-9.  Since the apparent outburst in Nov. 1977
the average e-folding decay time, measured by the Ariel 5 all-sky
monitor, has been ~ 45 days, and this is consistent with the present
A2 intensity.  Preliminary wide-band spectral colors are indicative
of a steep spectrum peaked at E ~ 3 keV.

     The HEAO A1 experimenters also report that the x-ray intensity
of Nova Oph 1977 = H 1705-25 (cf. IAUC 3104, 3110) was ~ 10**-10 erg
cm**-2 s**-1 (1-10 keV) on Mar. 9.

4U 1837+04 AND 4U 1538-52
     J. van Paradijs, University of Amsterdam and Massachusetts
Institute of Technology, reports that observations (dispersion 170
A/mm) with the European Southern Observatory's 360-cm reflector
reveal that Davidsen's (IAUC 2824) candidate for 4U 1837+04 = Ser X-1
shows a continuum without evidence for absorption or emission; of
two principal candidates for 4U 1538-52 (Cowley et al. 1977, Astrophys.
J. 218, L3) star 12 has an early type spectrum and star 10 a
strong G band and 4226 A Ca I, suggesting star 12 as more probable.

     E. P. Aksenov, Sternberg Astronomical Institute, reports that
N. E. Kurochkin has observed variability in the optical counterpart
(Matthews et al. 1964, Astrophys. J. 140, 35) of 3C 382 = B2 1833+32;
on 1962 Feb. 26 and 1968 June 6 its photographic magnitude was
~ 17, on 1973 July 6 near 15, while 14 plates between Sept. 1976
and May 1977 show brightening from mpg 16 to 15.  The nucleus of
the Seyfert galaxy MCG 8-11-11 = 2A 0551+466 (Ward et al. 1977,
Astron. Astrophys. 59, L19) also seems to be variable; in Nov. 1952
and Feb. 1953 its photographic magnitude was 14.6, while six plates
between Jan. 1976 and Apr. 1977 show brightening from 15.3 to 14.8.

1978 March 21                  (3197)              Brian G. Marsden

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