[vsnet-alert 822] CVC 131 (SX LMi, AQ CMi)

[Tonny Vanmunster <tvanmuns@innet.be>]

BELGIAN ASTRONOMICAL SOCIETY V.V.S. -  Working Group Variable Stars
Cataclysmic Variables Circular No.131                1997, April 06
Ed.: T. Vanmunster, Walhostraat 1A, 3401 Landen, BELGIUM
     Internet: tvanmuns@innet.be                  TEL. 32-11-831504
     CBA Belgium Web Page : http://vsnet.astro.columbia.edu/~cba/be
===================================================================

SX LMi [UGSU, 16B]
==================

Timo Kinnunen, Finland reports an outburst detection of this CVAP 
object. A confirmative observation was reported by Jochen Pietz,
Germany, while both Tonny Vanmunster and Eric Broens, Belgium
made independent outburst detections. All observations are listed
below.

1997 Apr 2.89  UT, <15.6    (T. Kinnunen, 0.44-m refl., visual);
     Apr 6.82  UT, >mag 14  (T. Kinnunen, visual);
     Apr 6.82  UT,  13.6    (J. Pietz, visual);
     Apr 6.898 UT,  13.4    (T. Vanmunster, 0.35-m refl., visual);
     Apr 6.913 UT,  13.9    (E. Broens, 0.35-m refl., visual);

Given the brightness of the present outburst, it most likely is a
superoutburst. Unfiltered CCD photometry is currently ongoing at
CBA Belgium.

In a reaction on the current outburst detection, Gary Poyner, UK
notes that the two positive SX LMi sightings, that he reported
at the end of March, very likely relate to a precurser outburst.
His observations were :

1997 Mar 26.933 UT,  15.2:  (G. Poyner, 0.40-m refl., visual);
     Mar 27.021 UT,  15.4:  (G. Poyner); 
     Mar 28.967 UT, <15.5   (G. Poyner);

SX LMi was last seen in outburst on June 3, 1996 by T. Vanmunster
[CVC 97] at mag. 13.2. It remained visible for 5 nights [CVC 98].
Based on the available observations, it was impossible to determine
the type of that outburst.

SX LMi was for the first time identified as an SU UMa type dwarf nova
by the Ouda Team at Kyoto University, Japan, in December 1994. Their
observations revealed superhumps with an amplitude of approx. 0.3 mag. 
Preliminary reductions gave as a best estimate for the superhump 
period a value of 100 min.


AQ CMi [UGSU, 14.5p - <16.5p]
=============================

The AQ CMi outburst reported in our previous CVC issue is over,
as one can derive from the observations below. 

1997 Mar 26.879 UT, <15.3  (G. Poyner, 0.40-m refl., visual);
     Mar 28.88  UT,  14.5  (J. Pietz, visual);
     Mar 29.839 UT,  14.3  (G. Poyner, visual);
     Mar 29.869 UT,  14.4  (G. Poyner, visual);
     Mar 30.44  UT,  14.5V (T. Kato, 0.60-m refl., CCD+V);
     Mar 31.844 UT,  15.0  (G. Poyner, visual);
     Apr 02.86  UT, <14.6  (T. Kinnunen, visual);

It was a superoutburst, according to CCD photometry done at Ouda 
Station, Kyoto University, Japan by the team of Taichi Kato, as
reported in a VSNET message : "V-band photometry ... revealed fully 
grown superhumps with an amplitude of ~0.22 mag in the present 
outburst of AQ CMi, confirming the suggestion of the current outburst 
being a superoutburst (vsnet-alert 812) ..."


CORRECTION
==========

Our previous CVC issue erroneously was labeled "CVC 129" instead of
"CVC 130".


Tonny Vanmunster

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