A Magnetic Pressure Difference Rule on Moving Bipolar Pores

Abstract Solar pores are transient dark spots in the continuum images of the Sun. Their dynamics are closely associated with solar magnetic fields and plasma motion. Their motions have been found to be correlated with their magnetic pressure differences. This work is aimed to investigate possible reasons for this correlation. Our examination of 19 pairs of bipolar pores reveals a magnetic pressure difference rule between the pores of a same pair: their signs of the differences between the magnetic pressures at the front and back sides are always opposite, and their directions of the maximum positive difference between the magnetic pressures at the opposite ends are always both pointing toward the left or right and are always slightly toward the higher latitudes. The rule indicates that the properties of the bipolar pores are influenced by the solar global magnetic fields and rotation.