标题： 在Hinode/EIS观测的日冕环中传播的慢磁声波 显示英文标题

标题： Propagating slow magnetoacoustic waves in coronal loops observed by Hinode/EIS

摘要： 我们展示了首次Hinode/EIS在日冕环足点处对过渡区谱线（He II）和五条日冕谱线（Fe X，Fe XII，Fe XIII，Fe XIV和Fe XV）中检测到的5分钟准周期振荡的观测结果。 这些振荡在整个观测期间存在，表现为一系列具有几乎恒定期限的波包，通常持续4-6个周期，寿命为20-30分钟。 多普勒位移和强度振荡之间存在近似同相关系。 这为从过渡区向日冕传播的慢磁声波提供了证据。 我们发现五条日冕谱线中检测到的振荡高度相关，并且振幅随着温度的增加而减小。 多普勒位移振幅减少了约3倍，而相对强度振幅从Fe X到Fe XV减少了约4倍。 这些振荡可能是光球p模通过色球层和过渡区泄漏到日冕引起的，这已被认为是之前由TRACE观测到的强度振荡的来源。 振荡振幅的温度依赖性可以通过沿着具有多股结构的环传播的波的阻尼来解释。 因此，这一特性可能在日冕地震学中具有诊断日冕环温度结构的潜在价值。 显示英文摘要

摘要： We present the first Hinode/EIS observations of 5 min quasi-periodic oscillations detected in a transition-region line (He II) and five coronal lines (Fe X, Fe XII, Fe XIII, Fe XIV, and Fe XV) at the footpoint of a coronal loop. The oscillations exist throughout the whole observation, characterized by a series of wave packets with nearly constant period, typically persisting for 4-6 cycles with a lifetime of 20-30 min. There is an approximate in-phase relation between Doppler shift and intensity oscillations. This provides evidence for slow magnetoacoustic waves propagating upwards from the transition region into the corona. We find that the oscillations detected in the five coronal lines are highly correlated, and the amplitude decreases with increasing temperature. The amplitude of Doppler shift oscillations decrease by a factor of about 3, while that of relative intensity decreases by a factor of about 4 from Fe X to Fe XV. These oscillations may be caused by the leakage of the photospheric p-modes through the chromosphere and transition region into the corona, which has been suggested as the source for intensity oscillations previously observed by TRACE. The temperature dependence of the oscillation amplitudes can be explained by damping of the waves traveling along the loop with multithread structure near the footpoint. Thus, this property may have potential value for coronal seismology in diagnostic of temperature structure in a coronal loop.