报告题目：Foreshock transients: formation mechanism and particle acceleration

　　报告人：刘子谞 博士（UCAR和阿拉斯加大学费尔班克斯分校）

　　2019/09至今：UCAR和阿拉斯加大学费班克斯分校 博士后研究员

　　2018/06-2019/09：加州大学洛杉矶分校（UCLA）地球、行星与空间科学系 助理研究员

　　2013/09-2018/06：加州大学洛杉矶分校（UCLA）地球、行星与空间科学系 博士

　　2009/09-2013/07：北京大学地球与空间科学学院 学士

　　报告摘要：Foreshock transients are ion kinetic structures in the ion foreshock. Due to their dynamic pressure perturbations, they can disturb the bow shock, magnetosheath, magnetopause, and magnetosphere-ionosphere system. Recent studies found that they can also accelerate particles. Acceleration mechanisms including shock drift acceleration, Fermi acceleration, betatron acceleration, and magnetic reconnection have been identified from observations and simulations. Our results suggest that foreshock transients could play a role in particle acceleration at the parent bow shock. Although they are important, how they form is still unclear. Using particle-in-cell simulations and MMS observations, we propose a physical formation process that the positive feedback of foreshock ions on the varying magnetic field caused by the foreshock ion Hall current enables an “instability” and the growth of the structure.

　　报告时间：2021年1月14日，星期四, 上午10:00

　　报告地点：腾讯会议，会议ID为 821 105 936

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