| 摘要: | 準週期脈動是一種可在不同波段(短至X射線長至無線電波)的時變曲線都觀測到的類波動現象，且各波段所觀測到的週期並不相同，從毫秒量級至數十分鐘都有，另在相同波段常可觀測到多重週期的脈動。而關於準週期脈動的產生機制目前仍未有一致性的結論，可能由於鄰近磁重聯區的日冕磁管結構振盪所觸發，也可能與週期性的能量釋放或磁重聯過程、閃焰磁管束的磁流體波模振盪有關。本計畫將專注於兩種準週期脈動現象的研究，即閃焰爆發前與三型無線電爆的脈動事件，利用地面測站(例如：SBRS、NoRH及NoRP)與衛星(例如：RHESSI、Fermi/GBM、SDO/AIA及IRIS)的多波段觀測資料，定量此兩種類型的脈動週期特性，定位其產生源區與相關結構，並探討譜線特性，試圖釐清準週期脈動與觸發閃焰之間的關聯性，瞭解磁重聯與各種波模在準週期脈動所扮演的角色，期望能提供太陽閃焰起始條件與粒子加速的重要參考資訊。 ;Recently, it has become clear that quasi-periodic pulsation (QPP), which is characterized as the periodic variations in light curves from radio to hard X-ray emissions, is a common and intrinsic feature in solar flares. The observed periods are various in different wavelengths ranging from milliseconds to tens of minutes. Moreover, multiple periods are often observed in the same wavelength. The trigger mechanism of QPP is still unclear, which is likely to be associated with the external oscillatory triggers, the periodicity of magnetic reconnection or energy release, and the MHD oscillations in flaring loops. In this project, we particularly concentrate on two kinds of QPP signatures, namely, pre-flare QPPs and repetitive Type III radio bursts. By means of the multi-wavelength ground-based (e.g., SBRS, NoRH, and NoRP) and spacecraft (e.g., RHESSI, Fermi/GBM, SDO/AIA, and IRIS) observations, we will quantify the temporal behaviors of QPPs, identify the source regions and corresponding structures, and investigate the spectral properties. We attempt to clarify the relationship between pre-flare QPPs and the subsequent flare eruptions, as well as the effects of magnetic reconnection and wave oscillations on the studied QPP events. We hope this research work can provide helpful information for understanding the flare initiation and particle acceleration from the perspective of QPPs. |
