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IAUC 7087: Var IN THE LMC; RX J0052.1-7319; N Mus 1998

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                                                  Circular No. 7087
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)
URL http://cfa-www.harvard.edu/iau/cbat.html  ISSN 0081-0304
Phone 617-495-7244/7440/7444 (for emergency use only)


VARIABLE IN THE LARGE MAGELLANIC CLOUD
     A. Becker, University of Washington, on behalf of the MACHO
collaboration (cf. IAUC 6312, plus F. Winkler and D. Paul,
Middlebury College), reports the discovery of a possible nova in
the LMC, located within 0".35 of a previously visible stellar
object at R.A. = 5h35m32s.27, Decl. = -69o29'52".1 (equinox
2000.0), which normally appears at R = 20.5, V = 21.0.  This object
was constant in brightness in over 900 frames taken between 1993
and 1998 at the Mt. Stromlo 1.27-m telescope.  Images taken on 1998
Dec. 28.691 UT indicated a slight brightening of 0.1 mag.  Sparse
observations over the next 2 weeks trace a rapid increase in
brightness, and the most recent observation taken on 1999 Jan.
11.742 indicates that the object is still brightening, with R =
16.9, V = 17.1.  Spectra taken on Jan. 14.059 at the Cerro Tololo
1.5-m telescope by F. Winkler display narrow H emission features,
plus [O III] 495.9, 500.7 nm; [N II] 654.8, 658.4 nm; and [S II]
671.7, 673.1 nm, from surrounding nebulosity evident in the images.
The [S II]/[N II] ratio is anomalously high (about 1.5).  The only
spectral features that can be attributed to the brightening source
are two broad absorption troughs centered at 441.8 and 513.7 nm.
Finding charts can be found by anonymous ftp to
darkstar.astro.washington.edu:macho/LMC_Nova.


RX J0052.1-7319
     P. Kahabka, University of Amsterdam, confirms the detection of
15.3-s pulsations for the x-ray pulsar RX J0052.1-7319 in the Small
Magellanic Cloud (cf. IAUC 7081, 7082) during a 1550-s ROSAT HRI
observation performed on 1996 Oct. 19.464-19.486 UT at an 8-sigma
confidence level.  The source has been detected at a large off-axis
angle of 21' with a countrate of about 0.27 sE-1 (applying a
vignetting correction factor of 1.2).  The observation was
performed about 1 month before the beginning of the 1996 Nov. 10-
Dec. 9 outburst (IAUC 7081) and with a countrate that is about a
factor of 2 lower.


NOVA MUSCAE 1998
     Visual magnitude estimates by A. Pearce, Nedlands, W.
Australia:  Jan. 5.642 UT, 11.1; 6.624, 11.3; 7.62, 11.3; 8.63,
11.5; 9.60, 11.6; 10.66, 11.7; 11.79, 11.7; 12.80, 11.7; 14.79,
11.9; 16.81, 12.0.

                      (C) Copyright 1999 CBAT
1999 January 16                (7087)            Daniel W. E. Green

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