A Spectroscopic Study of the SU UMa-type Dwarf Nova YZ Cnc during its 2002 Superoutburst

作     者：Ying-He Zhao Zong-Yun Li Xiao-An Wu Qiu-He Peng 

作者机构：Department of Astronomy Nanjing University Nanjing 210093 

出 版 物：《Chinese Journal of Astronomy and Astrophysics》 (中国天文和天体物理学报（英文版）)

年 卷 期：2005年第5卷第6期

页      面：601-609页

核心收录：

学科分类：0709[理学-地质学] 07[理学] 0708[理学-地球物理学] 070401[理学-天体物理] 0704[理学-天文学] 0825[工学-航空宇航科学与技术] 

基　　金：Supported by the National Natural Science Foundation of China 

主　　题：accretion, accretion disks -binaries close - novae, cataclysmic variables - stars dwarf novae - stars individual (YZ Cancri) 

摘      要：We report on time-resolved spectroscopic observations of the SU Ursae Majoris dwarf nova, YZ Cnc for over llh on two nights during its 2002 January superoutburst. The spectra on the first day only showed absorption-line profiles, while on the second day the lines showed “W profiles with blue and red troughs. The radial velocity curve of the absorption troughs and emission peaks of H/3 has an amplitude of 49±10 km s^-1 and a phase offset of -0.07±0.04, which are very similar to those measured in quiescence. However, the γ velocity deviates strongly from the systemic velocity measured in quiescence, by some ±60 km s^-1. Large shifts of -70 km s^-1 in the orbital-averaged velocity and -0.09 in the phase are also found in our observations. All these features can be well explained by a precessing, eccentric disk.