Magnetic vector field above a sunspot


Gömöry P.1,2, Balthasar H.1

1 Astrophysikalishes Institut Potsdam, An der Sternwarte 16, 14482 Potsdam, Germany
2 Astronomical Institute of the Slovak Academy of Sciences, SK-05960 Tatranská Lomnica, Slovakia


Abstract: 
We present an analysis of the spectro-polarimetric measurements of the active region NOAA 10886 taken with the Tenerife Infrared Polarimeter in the Fe I 10783 A spectral line. The magnetic field strength and the magnetic inclination and azimuth were inferred from the data using the inversion code SIR. The vertical current densities and the vertical derivative of the vertical component of the magnetic field were then calculated for the leading spot of the AR 10886. We revealed that typical values of the vertical current densities vary in the range +-40 mA/m^(2) inside the spot. Moreover, we found an extended area of enhanced vertical current densities in the umbra (values up to -80 mA/m^(2)). Our analysis also showed that the vertical component of the magnetic field strength decreases by 0.6 - 1.6 G/km^(1) and 0.5 - 0.8 G/km^(1) in the umbra and inner penumbra, respectively. On the other hand, we found an increase of the vertical component of the magnetic field in the outer penumbra (typical values vary between 0.1 - 0.5 G/km^(1)).