Evidence for magnetoconvection in sunspot umbral dots

被引：33

作者：

Bharti, Lokesh

Jain, Rajmal

Jaaffrey, S. N. A.

机构：

[1] Dept Space, Phys Res Lab, Ahmadabad 380009, Gujarat, India

[2] Mohanlal Sukhadia Univ, Coll Sci, Dept Phys, Udaipur 313001, India

来源：

ASTROPHYSICAL JOURNAL | 2007年 / 665卷 / 01期

关键词：

Sun : granulation; Sun : magnetic fields; Sun : photosphere; sunspots;

D O I：

10.1086/521024

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

An analysis of high-resolution Dopplergrams and continuum images of NOAA AR 8350 is presented. The observations were recorded with the universal birefringent filter attached to the Dunn Solar Telescope at the National Solar Observatory, Sunspot, New Mexico. We find upward velocity of the order of 400 m s within (-1) umbral dots, surrounded by downward velocity of the order of 300 m s. This observation is compatible with (-1) the simulations of three-dimensional radiative magnetoconvection with gray radiative transfer in sunspot umbra by Schussler & Vogler, which support the idea that umbral dots appear as a result of magnetoconvection.

引用

页码：L79 / L82

页数：4

共 31 条

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[3]

Biermann L., 1941, VIERTELJAHRESSCHR AS, V76, P194

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