Parkes observations for project P1018 semester 2019APRS_08

Stellar flares and coronal mass ejections (CMEs) may significantly impact the habitability of their planetary companions. M-dwarfs are particularly interesting in this regard, as they are known to flare more frequently and powerfully than the Sun, and a large fraction of them are likely to host planets within their habitable zones. To fully characterise the impact of stellar activity and space weather events on companion planets, a sustained, multi-wavelength campaign is required to trace particle acceleration and energisation occurring in distinct regions of the stellar magnetosphere. The discovery of an Earth-like exoplanet orbiting within the ‘habitable zone’ of the active M-dwarf Proxima Centauri has spurred renewed interest of this system in the literature. At just 1.3 pc away, this system is ideal for developing our understanding of the impact of space weather events on Earth-like planets around active stars. As part of a large, multi-wavelength international campaign we are proposing 60 hours of Parkes Radio Telescope observations targeting Proxima Centauri, using the new UWL receiver. The large instantaneous bandwidth and high time-resolution capability of the Parkes UWL receiver will allow us to comprehensively characterise radio bursts at gigahertz frequencies. This will provide important diagnostics of the magnetospheric environment of this star, and may enable direct observation of space weather events such as CMEs. If successful, these observations will be a key part of an extensive campaign that will significantly improve our understanding of our nearest stellar neighbour.

恒星耀斑与日冕物质抛射（coronal mass ejections, CMEs）可能会对其行星伴星的宜居性产生显著影响。M型矮星（M-dwarfs）在该研究领域中尤为值得关注：已知其耀斑爆发的频率与强度均远超太阳，且其中很大一部分极有可能在宜居带（habitable zones）内拥有行星。为全面表征恒星活动与空间天气事件对行星伴星的影响，需要开展持续的多波段观测计划（multi-wavelength campaign），以追踪发生在恒星磁层（stellar magnetosphere）不同区域的粒子加速与能量激发过程。围绕活动M型矮星比邻星（Proxima Centauri）宜居带内运行的类地系外行星（exoplanet）的发现，重新激发了学界对该系统的研究热情。该系统仅距地球1.3秒差距（pc），是我们理解活动恒星周围类地行星所受空间天气事件影响的理想研究对象。作为一项大型国际多波段观测计划的组成部分，我们拟利用新型UWL接收机（UWL receiver），申请60小时的帕克斯射电望远镜（Parkes Radio Telescope）观测时间，以对准比邻星开展观测。帕克斯射电望远镜搭载的UWL接收机具备超大瞬时带宽与高时间分辨率能力，可让我们全面表征吉赫兹（gigahertz）频段的射电爆发事件。这将为该恒星的磁层环境提供关键诊断信息，还有望直接观测到日冕物质抛射等空间天气事件。若观测顺利，这些观测数据将成为一项大型综合观测计划的核心组成部分，大幅提升我们对这颗距离地球最近的恒星邻居的认知水平。