Odessa Astronomical Publications (Dec 2010)
POSITIVE AND NEGATIVE SUPERHUMPS OF THE DWARF NOVA MN DRA
Abstract
We present the result of O–C analysis of the dwarf nova MN Dra. It is based on the multi-site photometric observations that were made over 77 nights in August – November, 2009. The total exposure was 433 hours. During this time binary underwent two superoutbursts and five normal outbursts. In superoutbursts the positive superhumps decreased with extremely large P = -(3 - 8) x 10-4 for SU UMa-like dwarf novae, confirming the known behavior of MN Dra in 2003. MN Dra displayed large-amplitude (up to 1.4m in quiescence and 0.1m–0.2m in normal outbursts) negative superhumps. The improved value of negative superhump period is 0.095952(4) d.