激变变星Ⅴ1159 Ori 和BZ UMa 的测光研究

Ⅴ1159 Ori 是SU UMa 型中 ER UMa 亚型激变变星,BZ UMa 介于 U Gem 型和 WZ Sge 型之间,但又具有 SU UMa 的周期特征,存在争议.在2008年2月24日和 25日,用云南天文台 1 米 RCC(Ritchey-Chretien-Coude)望远镜对两者的测光观测显示: Ⅴ1159 Ori 在正常爆发的下降阶段存在 superhump,这为 superhump 现象普遍存在于 ER UMa 型星中提供了观测证据;BZ UMa 观测时处于爆发极大,并未观测到确凿的 superhump 周期,而 AAVSO(American Association of Variable Star Observers)近年的 BZ UMa 观测亦从未发现明确的 superhump;两者均表明 BZ UMa 可能并非 SU UMa 型星.基于星等变化幅度考虑,BZ UMa 较 WZ Sge 更为接近.

The Photometry of Cataclysmic Variable Ⅴ1159 Ori and BZ Uma

Photometry of the cataclyrsmic variables Ⅴ1159 Ori and BZ UMa are con-ducted with the 1m RCC optical telescope in Yunnan Astronomical Observatory from Feb.24th to 25th,2008.The light curves of Ⅴ1159 Ori denote superhumps during the fading period of a normal outburst.Previous observations revealed superhumps in ER UMa during normal outbursts,convincing that it is universal in ER UMa class.This photometry helps to assure superhumps'presence in ordinary outbursts of ER UMa class.As to the controversial BZ UMa,whose orbital period is below the period gap of SU Uma,no apparent observable superhumps are detected in either previous observations or that of this time.Therefore,it is more likely to side with U Gem class or WZ Sge class,with the latter of more likelihood.