Estimating the chromospheric magnetic field from a revised NLTE modeling: the case of HR 7428

被引:0
作者
Busa, Innocenza [1 ]
机构
[1] INAF Catania Astrophys Observ, Via S Sofia 78, I-95123 Catania, Italy
来源
LIVING AROUND ACTIVE STARS | 2017年 / 12卷 / S328期
关键词
magnetic field; stars: chromospheres; stars: modeling atmosphere; stars: activity; TRANSITION REGION; FLARE STARS; II PEGASI; EMISSION; ALPHA; PROFILES;
D O I
10.1017/S1743921317003684
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
Semi-empirical atmospheric modeling is here used to obtain the chromospheric magnetic field distribution versus height in the K2 primary component of the RS CVn binary system HR 7428. The chromospheric magnetic field estimation versus height comes from considering the possibility of not imposing hydrostatic equilibrium in the atmospheric modeling. The stability of the best Non-hydrostatic equilibrium model, implies the presence of and additive (toward the center of the star) pressure, that decrease in strength from the base of the chromosphere toward the outer layers. Interpreting the additive pressure as magnetic pressure and I derive a magnetic field intensity of about 500 Gauss at the base of the chromosphere.
引用
收藏
页码:38 / 45
页数:8
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