Modeling Stellar Exotica in Dense Star Clusters

瓦萨尔学院将开展一个由瓦萨学院和西北大学合作的项目，该项目将探索恒星之间近距离相互作用过程中磁场的影响，这种情况很可能在密集恒星环境(例如球状星团的核心)中经常发生。这种相互作用不仅决定了这些星系团的命运，也被认为是蓝色散布星、双星脉冲星和X射线源等奇异天体的起源。Vassar的研究人员和学生将使用之前NSF资助下开发的3D平滑粒子流体动力学代码，并完成其修改以包括磁场(3D平滑粒子流体动力学代码)。这个新的工具将被用来模拟不同类型的恒星(主序星、亚巨星、红巨星和恒星残留物)之间的恒星碰撞/合并。具体的主题包括球状星团中的恒星碰撞(以及蓝散星的起源，即碰撞和合并)、双星合并和共同的包络演化。这个项目包括学生的大量参与，目标是建立自我维持的学生研究项目(在这些项目中，新学生由高年级学生培训)。任何一所学校的学生都有机会与另一所学校的学生/博士后研究员/教职员工进行合作。同样，还将培养学员在编程、建模、流体力学/流体力学等方面的有用技能。

AST-0507561James LombardiVassar CollegeModeling Stellar Exotica in Dense Star ClustersABSTRACTA collaborative project between Vassar College and Northwestern University will be undertakenwhich will explore the effects of magnetic fields during close interactions between stars as are likelyto take place frequently in dense stellar environments (e.g., the cores of globular clusters). Suchinteractions not only determine the fate of these clusters but are also believed to be the origin ofexotic objects such as blue stragglers, binary pulsars, and x-ray sources. The investigators andstudents at Vassar will use a 3D smoothed particle hydrodynamics code developed under previousNSF funding and complete its adaptation to include magnetic fields (a 3D smoothed particlemagnetohydrodynamic code). This new tool will then be used to simulate stellar collisions/mergersamong a variety of types of stars (main-sequence, subgiant, red giant, and stellar remnants).Specific topics that will be addressed include stellar collisions in globular clusters (and the originsof blue stragglers, i.e., collisions versus mergers), binary mergers, and common envelope evolution.Included in this project is significant involvement by students with the goal of setting up self -sustaining student research programs (in which new students are trained by seniors). There is alsothe opportunity for students at either school to become involved in collaborations withstudents/postdoctoral fellows/faculty at the other. Likewise, useful skills in programming,modeling, hydrodynamics/fluid mechanics, etc., will be developed among the participants.