Chromospheric magnetic reconnection caused by photospheric flux emergence: implications for jet-like events formation
Chromospheric magnetic reconnection caused by photospheric flux emergence: implications for jet-like events formation
复制标题
DOI：
10.1051/0004-6361/200913101
复制
发表时间：
2009-12
影响因子：
6.5
通讯作者：
J. Ding;M. Madjarska;J. Doyle;Q. Lu
中科院分区：
文献类型：
--
作者：
J. Ding;M. Madjarska;J. Doyle;Q. Lu
在不同的物理环境中，研究了低层大气中的磁重联，例如色球。讨论了它对爆炸性事件(小规模喷流)的起源的影响。采用笛卡尔坐标下的2.5维阻磁流体力学模型。结果表明，由于磁重联而产生的外流射流的温度和速度强烈地依赖于物理环境，例如磁场强度和等离子体密度的大小。当磁场强度较弱、密度较高时，射流的温度很低(~104K)，速度很低(~40公里S-1)。然而，如果考虑磁场强度较强(40G)和密度较小(电子密度Ne=2×1010 cm-3)的环境，外流急流的温度高达6×105K，视线速度高达130kM S-1，与类喷流事件的观测值相当。
Magnetic reconnection in the low atmosphere, e.g. chromosphere, is investigated in various physical environments. Its implications for the origination of explosive events (small-scale jets) are discussed. A 2.5-dimensional resistive magnetohydrodynamic (MHD) model in Cartesian coordinates is used. It is found that the temperature and velocity of the outflow jets as a result of magnetic reconnection are strongly dependent on the physical environments, e.g. the magnitude of the magnetic field strength and the plasma density. If the magnetic field strength is weak and the density is high, the temperature of the jets is very low (~10 4 K) as well as its velocity (~40 km s -1 ). However, if environments with stronger magnetic field strength (40 G) and smaller density (electron density N e = 2 × 10 10 cm -3 ) are considered, the outflow jets reach higher temperatures of up to 6 × 10 5 K and a line-of-sight velocity of up to 130 km s -1 which is comparable with the observational values of jet-like events.