Electric resistivity of partially ionized plasma in the lower solar atmosphere  

作　　者：Jongchul Chae Yuri ELitvinenko 

机构地区：[1]Astronomy Program,Department of Physics and Astronomy,Seoul National University,Seoul 08826,Korea [2]Department of Mathematics,University of Waikato,P.B.3105,Hamilton 3240,New Zealand

出　　处：《Research in Astronomy and Astrophysics》2021年第9期193-201,共9页天文和天体物理学研究（英文版）

基　　金：supported by the National Research Foundation of Korea(NRF-2020R1A2C2004616);the support by the Deutsche Forschungsgemeinschaft project(434200803)。

摘　　要：The lower solar atmosphere is a gravitationally stratified layer of partially ionized plasma.We calculate the electric resistivity in the solar photosphere and chromosphere,which is the key parameter that controls the rate of magnetic reconnection in a Sweet-Parker current sheet.The calculation takes into account the collisions between ions and hydrogen atoms as well as the electron-ion collisions and the electron-hydrogen atom collisions.We find that under the typical conditions of the quiet Sun,electric resistivity is determined mostly by the electron-hydrogen atom collisions in the photosphere,and mostly by the ion-hydrogen collisions,i.e.ambipolar diffusion,in the chromosphere.In magnetic reconnection events with strong magnetic fields,the ambipolar diffusion,however,may be insignificant because the heating by the reconnection itself may lead to the full ionization of hydrogen atoms.We conclude that ambipolar diffusion may be the most important source of electric resistivity responsible for the magnetic flux cancelation and energy release in chromospheric current sheets that can keep a significant fraction of neutral hydrogen atoms.

关 键 词：PLASMAS atomic processes magnetohydrodynamics(MHD) Sun:atmosphere Sun:chromosphere 

分 类 号：P182.2[天文地球—天文学]