Special Notice #367: Outburst of the UGWZ star UZ Bootis

July 26, 2013

Carey Chiselbrook (CCY; Georgia, United States) reports via the AAVSO Forums that the WZ Sge-type variable UZ Bootis is in outburst.  It was observed visually at magnitude 12.8 on 2013 Jul 26 02:00 UT (JD 2456499.58194).  The outburst was confirmed by Walter MacDonald (MDW; Ontario, Canada) imaged the field and found UZ Boo at V=12.69 03:25 UT (JD 2456499.6394).  Observations of UZ Bootis -- both visual estimates and CCD time series -- are encouraged throughout the outburst.

As was noted by Gary Poyner on the BAAVSS-alert mailing list, the last outburst of UZ Boo was in 2003.  That outburst showed multiple rebrightenings, and observers should continue monitoring the star even after it appears to decline for the first time because it may reappear several times.  CCD observers may use a V filter or perform unfiltered photometry when the source becomes faint.  The star should exhibit superhumps, and observers should keep integration times as short as possible to achieve good S/N (preferably > 20-30).

UZ Boo is located at the following (J2000) coordinates:

RA: 14:44:01.21 , Dec: +22:00:54.7

Please promptly report all observations to the AAVSO using the name "UZ BOO".

This AAVSO Special Notice was prepared by M. Templeton.