BELGIAN ASTRONOMICAL SOCIETY V.V.S. -  Working Group Variable Stars
Cataclysmic Variables Circular No.133                1997, April 09
Ed.: T. Vanmunster, Walhostraat 1A, 3401 Landen, BELGIUM
     Internet: tvanmuns@innet.be                  TEL. 32-11-831504
     CBA Belgium Web Page : http://www.astro.columbia.edu/~cba/be
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SX LMi [UGSU, 16B]
==================

Additional time-series photometry at CBA Belgium Observatory,
using a 0.25-m SCT and ST-7 CCD, on April 8/9 1997 during 3.9 
hours shows prominent and full-grown superhumps. A first analysis 
of the superhump period using the PDM method yields a best value
of 0.0704 +- 0.0015 d and a mean semi-amplitude of 0.04 mag.


DV UMa [UGSU, 15.4v - 20.6v]
============================

T. Kato, Kyoto University, Japan notes an error in our previous
circular [CVC 132], which announced the present outburst detection.
The reported period of 0.08585 +- 0.00001 day refers to the 
ORBITAL period of the system and not the superhump period.

The suggested classification of DV UMa as a member of the SU UMa
type dwarf novae thus still needs to be confirmed.

An extensive multi-longitude photometry observation campaign on DV UMa
meanwhile has been initiated by the Centers for Backyard Astrophysics.

Kato further published an eclipse ephemeris of DV UMa, based on
eclipse timings measured by Howell, Nogami and Kato :

The best fit ephemeris is

  Min.HJD = 2446854.7487 + 0.085852614 E   

The second best (viable) solution is

  Min.HJD = 2446854.7483 + 0.085877839 E   


Tonny Vanmunster