High-frequency Waves in Chromospheric Spicules
High-frequency Waves in Chromospheric Spicules
复制标题
DOI：
10.3847/1538-4357/ac5c53
复制
发表时间：
2022-03
期刊：
影响因子：
--
通讯作者：
W. Bate;D. Jess;V. Nakariakov;S. Grant;S. Jafarzadeh;M. Stangalini;P. Keys;D. Christian;
中科院分区：
文献类型：
--
作者：
W. Bate;D. Jess;V. Nakariakov;S. Grant;S. Jafarzadeh;M. Stangalini;P. Keys;D. Christian;
利用邓恩太阳望远镜氢-α快速动力学相机成像系统的高节奏观测，我们提出了一个调查的统计特性的横向振荡在太阳翼上方捕获的针状。在五个相隔相等的大气高度，跨度约4900-7500 km，我们总共探测到15，959个单独的波事件，平均位移振幅为151 ± 124 km，平均周期为54 ± 45 s，平均投影速度振幅为21 ± 13 km s−1。我们发现，位移和速度振幅都随着太阳边缘以上的高度而增加，在4900 km处分别为132 ± 111 km和17.7 ± 10.6 km s−1，在7500 km处分别为168 ± 125 km和26.3 ± 14.1 km s−1。在检查了相邻的振荡在时间和空间上的情况后，我们发现45%的波是向上传播的，49%是向下传播的，6%是驻波，传播波的平均绝对相速度在75-150 km s−1的数量级。虽然向下传播的波的能量通量似乎不依赖于高度，但我们发现向上传播的波的能量通量以− 13，200 ± 6500 W m−2/Mm的速率随着大气高度而减少。
Using high-cadence observations from the Hydrogen-alpha Rapid Dynamics camera imaging system on the Dunn Solar Telescope, we present an investigation of the statistical properties of transverse oscillations in spicules captured above the solar limb. At five equally separated atmospheric heights, spanning approximately 4900–7500 km, we have detected a total of 15,959 individual wave events, with a mean displacement amplitude of 151 ± 124 km, a mean period of 54 ± 45 s, and a mean projected velocity amplitude of 21 ± 13 km s−1. We find that both the displacement and velocity amplitudes increase with height above the solar limb, ranging from 132 ± 111 km and 17.7 ± 10.6 km s−1 at ≈4900 km, and 168 ± 125 km and 26.3 ± 14.1 km s−1 at ≈7500 km, respectively. Following the examination of neighboring oscillations in time and space, we find 45% of the waves to be upwardly propagating, 49% to be downwardly propagating, and 6% to be standing, with mean absolute phase velocities for the propagating waves on the order of 75–150 km s−1. While the energy flux of the waves propagating downwards does not appear to depend on height, we find the energy flux of the upwardly propagating waves decreases with atmospheric height at a rate of −13,200 ± 6500 W m−2/Mm. As a result, this decrease in energy flux as the waves propagate upwards may provide significant thermal input into the local plasma.