Skip to main content

Special Notice #14: BZ UMa Outburst

June 22, 2006: Based on the following observations, BZ UMa appears to be in outburst:

JUN 22.1986 V 11.36 +/- 0.02 GKA

JUN 22.8854 Unf. 11.5 (rough) VMT

Thanks to Keith Graham (GKA) for discovering the outburst, Tonny Vanmunster (VMT) for confirming it and Eddy Muyllaert (MUY) for bringing it to our attention.

We need time series coverage for as long as possible. Nice, long observing runs are very important. We are looking for the possible emergence of quasi-periodic oscillations during the decline and they may not last very long, so large gaps in coverage may miss them. Outbursts are short and usually last only 3-4 days. However, a superoutburst is not out of the question for BZ UMa.

This is a very enigmatic CV that has thus far defied classification, despite good coverage photometrically and spectroscopically from both ground and space. Aim for 0.01 precision and go unfiltered if needed to obtain that level of accuracy. Time resolution is not as important as precision and the length of the total observing run.

The AAVSO International Database has terrific coverage of the past 3 outbursts of BZ UMa. For a summary of those outbursts and current knowledge of BZ UMa consult the following poster paper by Price & Howell (2005): http://www.aavso.org/news/price-aas.pdf (6MB)

Charts are available at: http://www.aavso.org/cgi-bin/searchcharts3.pl?name=bz%20uma [2014 chart link http://www.aavso.org/vsp]

Anyone who contributes significant data to the light curve will be a coauthor on any paper published by AAVSO staff.

This Special Notice was compiled by: Aaron Price

 

AAVSO 49 Bay State Rd. Cambridge, MA 02138 aavso@aavso.org 617-354-0484