Xiong Darun

AWARDEE OF ASTRONOMY SCIENCES PRIZE

XIONG DARUN

Xiong Darun, an astrophysicist, was born in September 1938 in Jiangxi Province. He graduated from Department of Geophysics of Peking University in 1962. Since 1962 he worked on Purple Mountain Observatory, Chinese Academy of Sciences. He is now a research professor of Purple Mountain Observatory. He was elected the academician of Chinese Academy of Sciences in 1991.The main fields of his research are the stellar convection theory and the relevant problems of stellar structure and evolution. He developed a statistical theory of non-local and time-dependent convection of stars. Using his own theory, he and his collaborators carried out the theoretical calculations of stellar structure, evolution and oscillations. The familiar so-called semi-convection contradiction brought by the local treatment of convection was removed and the mass contradiction of Cepheids may be also resolved. Their model of the non-local convection can interpret the main observed characteristics of the Sun. They studied the coupling between convection and oscillations of stars in detail. The complex behaviours of variable stars in H-R Diagram would be explicated. For example, the theoretical red edge of pulsating stability strip of RR Lyrae and δ Scuti stars can be determined and the pulsating stability strip of Mira outside the Cepheid instability strip was also explained. They found that all the luminous red variable stars are pulsating at fundamental and low-order modes. On the contrary, the intermediate- and low-luminosity red stars are stable in the fundamental and first modes, but they are pulsating at high (n>2) overtones.