Collaborative EAGER Proposal: The Dead Zones of Protoplanetary Disks are Not Dead - How Turbulence Transports Angular Momentum and Forms Planetesimals

EAGER奖资助了一项合作研究，以研究将在恒星周围形成行星的物质中气体和尘埃的湍流。 要研究的机制可能对形成未来行星核心的小岩石体很重要，而其形成过程却知之甚少。 这项研究对理解我们自己的太阳系和其他恒星周围行星的形成有潜在的影响。该研究将创建一个由本科生和研究生以及博士后学者组成的团队。我们的研究的协作性质将协同提供机会，为学生在旧金山弗朗西斯科州立大学，少数民族服务的非博士机构，与学生和教师在加州大学伯克利分校。研究人员还将培训和指导一名博士后研究人员。为了实现他们的科学目标，该团队将计算充满大幅湍流的原行星盘（PPD）死区中的角动量输运，计算湍流PPD中灰尘和岩石积聚和凝聚的速率，并计算PPD中的混合。特别是，他们将确定陨石球粒形成的成分是否充分混合，使其组成与观测结果一致。 他们还将通过扩展他们目前的谱代码（适用于滞弹性流），开发有效地进行上述动量传输计算的能力，使其适用于马赫数小于3的完全可压缩流（如死区）。该团队将开发有效执行上述星子和球粒形成计算的能力，方法是将他们的“粒子跟踪”代码替换为将岩石和尘埃模拟为流体流动的不同阶段的代码。

This EAGER award funds a collaborative study to study the turbulence of gas and dust in the material that will form planets around stars. The mechanism to be studied could be important in forming the small rocky bodies that are the cores of future planets, and whose process of formation is poorly understood. This study has potential impact in understanding the formation of our own Solar System and of the planets around other stars. The research will create a team consisting of undergraduate and graduate students, and postdoctoral scholars. The collaborative nature of our research will synergistically provide opportunities for students at San Francisco State University, a minority-serving non-PHD institution, to work with students and faculty at University of California at Berkeley. The investigators will also train and mentor a postdoctoral researcher.To accomplish their science goals, the team will compute angular momentum transport in a protoplanetary disk (PPD) dead zone filled with large-amplitude turbulence, compute the rate at which dust and rocks accumulate and agglomerate in a turbulent PPD, and compute mixing in a PPD. In particular, they will determine if the ingredients from which chondrules form become sufficiently mixed that their composition agrees with observations. They will also develop the capability to carry out the above-listed calculation of momentum transport efficiently by extending their current spectral code, which works with anelastic flows, to one that works with fully-compressible flows with Mach numbers less than 3 (as in dead zones). The team will develop the capability to carry out the above-listed calculations of planetesimal and chondrule formation efficiently by replacing their "particle-tracking" code with one that models the rocks and dust as different phases of the fluid flow.