An SPH simulation for cooling and self-gravitating protoplanetary disks

作     者：Kazem Faghei 

作者机构：School of PhysicsDamghan University 

出 版 物：《Research in Astronomy and Astrophysics》 (天文和天体物理学研究（英文版）)

年 卷 期：2013年第13卷第2期

页      面：170-178页

核心收录：

学科分类：07[理学] 070401[理学-天体物理] 0704[理学-天文学] 

基　　金：Acknowledgements I thank the anonymous referee for very useful comments that helped me to improve the initial version of the manuscript. I would also like to thank Markus Wetzstein for his very useful comments that helped me to perform my SPH simulation using the VINE code. The surface densities have been plotted by a code written by the author. The discussions with Soheil Khoshbinfar were very effective in converting my code to a GPU version. I also thank him for his help 

主　　题：accretion, accretion disks -- planetary systems protoplanetary disks -- planetary systems formation 

摘      要：We investigate the effects of the cooling function in the formation of clumps of protoplanetary disks using two-dimensional smoothed particle hydrody- namic simulations. We use a simple prescription for the cooling rate of the flow, du/dt = -u/τcool, where u and %ool are the internal energy and cooling timeseale, respectively. We assume the ratio of local＇cooling to dynamical timescale, Ωτcool =β, to be a constant and also a function of the local temperature. We found that for the constantβ and γ = 5/3, fragmentation occurs only forβ ≤ 7. However, in the case ofβ having temperature dependence and γ = 5/3, fragmentation can also occur for larger values ofβ. By increasing the temperature dependence of the cooling timescale, the mass accretion rate decreases, the population of clumps/fragments increases, and the clumps/fragments can also form in the smaller radii. Moreover, we found that the clumps can form even in a low mass accretion rate, ≤10-7M⊙yr-1, in the case of temperature-dependentβ. However, clumps form with a larger mass accretion rate, 〉 10-7M⊙ yr-1, in the case of constantβ.