The Slope of the Magnetic Field in Sunspots of Leading and Tail Polarity

In the paper, we examine the α inclination of the magnetic field of sunspots relative to the vertical. To determine the deviation angle α, a method to search for differences in the maximum of the longitudinal component of the magnetic field at various distances of spots from the central meridian in the eastern and western hemispheres of the Sun was used. Particular attention has been paid to the difference in the angles α for spots of leading and tail polarity of the magnetic field. Deviation angles α were shown to depend on the logarithm of the area while the dependences have opposite signs: α_L = 0.45°(±0.5) + 2.085°(±0.5) log S, (r = 0.95) for nuclei of leading polarity spots (L) and α_T = 5.43°(±1.0) – 3.95°(±0.7) log S, (r = 0.93) for nuclei of tail polarity (T). Here, the deviation of magnetic fields to the western limb is taken as a positive value. The found dependencies indicate the ascent of U-shaped force tubes.