Spectropolarimetery of umbral fine structures from Hinode: evidence for magnetoconvection

被引:11
作者
Bharti, Lokesh [1 ]
Joshi, Chandan [1 ]
Jaaffrey, S. N. A. [1 ]
Jain, Rajmal [2 ]
机构
[1] Mohanlal Sukhadia Univ, Univ Coll Sci, Dept Phys, Udaipur 313001, India
[2] Dept Space, Phys Res Lab, Ahmadabad 380009, Gujarat, India
关键词
Sun: granulation; Sun: magnetic fields; Sun: photosphere; sunspots; BAND CIRCULAR-POLARIZATION; PENUMBRAL FILAMENTS; SUNSPOT PENUMBRAE; MAGNETIC-FIELD; LIGHT BRIDGE; FLUX TUBES; DOTS; INVERSION; ORIGIN; PROFILES;
D O I
10.1111/j.1365-2966.2008.14203.x
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We present spectropolarimetric analysis of umbral dots and a light bridge fragment that show dark lanes in G-band images. Umbral dots show upflow as well as associated positive Stokes V area asymmetry in their central parts. Larger umbral dots show downflow patches in their surrounding parts that are associated with negative Stokes V area asymmetry. Umbral dots show weaker magnetic field in central part and higher magnetic field in peripheral area. Umbral fine structures are much better visible in total circularly polarized light than in continuum intensity. Umbral dots show a temperature deficit above dark lanes. The magnetic field inclination shows a cusp structure above umbral dots and a light bridge fragment. We compare our observational findings with 3D magnetohydrodynamic simulations.
引用
收藏
页码:65 / 70
页数:6
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