中国科大地空学院“瀚海问天”日地空间物理前沿论坛讲座第45期-Robert Wimmer-Schweingruber

报告人简介：

Robert Wimmer-Schweingruber，1994 年于瑞士伯尔尼大学获博士学位。在美国马里兰大学帕克分校完成博士后研究后，他受邀返回伯尔尼，负责该校在NASA Wind与ACE两项任务中的科研工作。此后他承担了一系列的重大任务，牵头了伯尔尼大学为NASA STEREO任务研制相关载荷。2001年，他在伯尔尼大学完成教授资格论文（Habilitation，venia docendi），研究方向为行星科学中的经典难题。2002年，他受聘于德国北部的基尔大学，担任全职教授，并主持地外物理分部。此后，他为多项空间任务研制了载荷，包括NASA好奇号(Curiosity)、中国嫦娥四号、欧空局太阳轨道飞行器（Solar Orbiter）以及德国的Heinrich-Hertz任务。

摘要：

The Energetic Particle Detector (EPD) onboard Solar Orbiter operates at an unprecedented high cadence up to one second, revealing previously unobserved behaviors of energetic particles. Suprathermal particles (up to a few tens of keV) and particles at hundreds of keV sometimes exhibit strong variability on timescales comparable to particle gyro-periods. We present multiple cases of unstable energy or velocity distributions together with their temporal evolution, and discuss candidate physical interpretations, such as time-dependent magnetic connection to distant acceleration sites and convection of magnetic structures passing the spacecraft. One striking event shows strong ion-flux variations in the Sun-pointing and south-pointing telescopes without obvious variations in pitch-angle or interplanetary magnetic field. Counter-intuitive arrival-time sequences are also observed: higher-energy particles arrive prior to lower-energy ones in the south telescope, whereas the Sun-ward telescope records the reversed order. Such findings further demonstrate how high-time-resolution particle measurements can usncover fine-scale physical processes hidden beneath lower-resolution observations.