用太阳和日光层观测站的太阳紫外线辐射光谱仪和横滨的布拉格晶体光谱仪在耀斑温度下形成的离子的发射线中观测到了阻尼多普勒频移振荡。这封信报告了用Hinode卫星上的EUV成像光谱仪观测到的在低得多的温度下形成的日冕发射线中的低振幅阻尼振荡。振荡的振幅约为2 km/s，周期约为35 min。衰减时间显示了与形成发射线最低温度相关的一些证据（Fe XII 195.12埃），表现出约43分钟的衰变时间，而最高形成温度发射线（Fe XV 284.16埃）在两个以上的振荡周期内没有表现出衰减的迹象。这些数据似乎与慢磁声驻波一致，但可能与传导阻尼不一致。
英文摘要：
Damped Doppler shift oscillations have been observed in emission lines from ions formed at flare temperatures with the Solar Ultraviolet Measurements of Emitted Radiation spectrometer on the Solar and Heliospheric Observatory and with the Bragg Crystal Spectrometer on Yohkoh. This Letter reports the detection of low-amplitude damped oscillations in coronal emission lines formed at much lower temperatures observed with the EUV Imaging Spectrometer on the Hinode satellite. The oscillations have an amplitude of about 2 km/s, and a period of around 35 min. The decay times show some evidence for a temperature dependence with the lowest temperature of formation emission line (Fe XII 195.12 Angstroms) exhibiting a decay time of about 43 min, while the highest temperature of formation emission line (Fe XV 284.16 Angstroms) shows no evidence for decay over more than two periods of the oscillation. The data appear to be consistent with slow magnetoacoustic standing waves, but may be inconsistent with conductive damping.
Flows and Non-thermal Velocities in Solar Active Regions Observed with the Extreme-ultraviolet Imaging Spectrometer on Hinode: A Tracer of Active Region Sources of Heliospheric Magnetic Fields?
Giant Chromospheric Anemone Jet Observed with Hinode and Comparison with Magnetohydrodynamic Simulations: Evidence of Propagating Alfven Waves and Magnetic Reconnection
High Resolution X-Ray Spectra of Capella: Initial Results from the Chandra High Energy Transmission Grating Spectrometer
覆盖能量范围为0.4-8.0 keV（1.5-30埃）的活动二元五车二（G8 III + G1 III）的高分辨率光谱显示出大量的发射线，证明了HETGS的性能。等离子体诊断的初步应用提供了有关日冕温度和密度的信息。由不同元素在不同电离状态下产生的谱线表明，五车二的等离子体具有广泛的温度范围，从log T = 6.3到7.2，这与极紫外探测器（EUVE）和宇宙学和天体物理学高级卫星（ASCA）最近的观测结果基本一致。电子密度由类He O VII谱线确定，在T_e=2*10^6 K时，N_e=10^10 cm^-3;在更高温度下形成的类He谱线只能给出电子密度的上限。O VII线的密度和发射测量一起表明日冕环明显小于恒星半径。
