摘要
We present a study on pulsations of the high-amplitudeδScuti star YZ Boo based on photometric observations in Johnson V and R bands with both the Nanshan 1-m telescope of Xinjiang Astronomical Observatory（XAO）and the Xinglong 85-cm telescope of National Astronomical Observatories,Chinese Academy of Sciences（NAOC）.Fourier analysis of the light curves reveals the fundamental radial mode and its five harmonics,with the fourth and fifth being newly detected.Thirtynine new times of maximum light are determined from the light curves,and combined with those in the literature,we construct the O-C diagram,derive a new ephemeris and determine a new value for the updated period of 0.104091579（2）.In addition,the O-C diagram reveals an increasing rate of period change for YZ Boo.Theoretical models are calculated and constrained with the observationally determined parameters of YZ Boo.The mass and age of YZ Boo are hence derived as M=1.61±0.05 M_⊙ and age=（1.44±0.14）×10~9 yr,respectively.With both the frequency of the fundamental radial mode and the rate of period change,YZ Boo is located at the post main sequence stage.
We present a study on pulsations of the high-amplitudeδScuti star YZ Boo based on photometric observations in Johnson V and R bands with both the Nanshan 1-m telescope of Xinjiang Astronomical Observatory（XAO）and the Xinglong 85-cm telescope of National Astronomical Observatories,Chinese Academy of Sciences（NAOC）.Fourier analysis of the light curves reveals the fundamental radial mode and its five harmonics,with the fourth and fifth being newly detected.Thirtynine new times of maximum light are determined from the light curves,and combined with those in the literature,we construct the O-C diagram,derive a new ephemeris and determine a new value for the updated period of 0.104091579（2）.In addition,the O-C diagram reveals an increasing rate of period change for YZ Boo.Theoretical models are calculated and constrained with the observationally determined parameters of YZ Boo.The mass and age of YZ Boo are hence derived as M=1.61±0.05 M_⊙ and age=（1.44±0.14）×10~9 yr,respectively.With both the frequency of the fundamental radial mode and the rate of period change,YZ Boo is located at the post main sequence stage.
基金
support from the National Natural Science Foundation of China(NSFC,Grant No.11273051)
partially supported by the Chinese Academy of Sciences(CAS) “Light of West China” program(2015-XBQN-A-02)
supported by the Strategic Priority Research Program of CAS(Grant No.XDB23040100)
support from the Joint Fund of Astronomy of NSFC and CAS(Grant U1231202 and 11673003)
the National Basic Research Program of China(973 Program 2014CB845700 and 2013CB834900)
the LAMOST FELLOWSHIP supported by Special Funding for Advanced Users,budgeted and administrated by the Center for Astronomical MegaScience,Chinese Academy of Sciences(CAMS)
support from the NSFC(No.11403088)
