抚仙湖太阳观测和研究基地知识库

We analyze six cases of magnetic reconnection with large separatrix angles and separatrix jets observed on the solar disk. The separatrix angle is defined as the angle between the two separatrices on the two sides of the outflow region. The plasma jets are observed immediately downstream of the separatrices. The morphological characteristics and magnetic field configurations of all magnetic reconnections are displayed. At the same time, we calculate several physical parameters of each case, which include the inflow velocity (from 2.3 to 24 km s(-1)), the outflow velocity (from 1.9 to 43 km s(-1)), the separatrix jet velocity (from 13 to 82 km s(-1)), the width (from 0.42 x 10(3) to 1.2 x 10(3) km) and length (from 1.4 x 10(3) to 4.3 x 10(3) km) of the current sheet, and the separatrix angle theta (sep) (from 72 degrees to 128 degrees). We find that the outflow velocity, the separatrix jet velocity, and the width and length of the current sheet are positively related to the inflow velocity, but the separatrix angle does not depend on the inflow velocity and it is related to the initial magnetic field configuration before magnetic reconnection. Meanwhile, the velocities of the outflow and the separatrix jet decrease with increasing vertical bar theta(sep)-90 degrees vertical bar, indicating that when the separatrix angle is close to 90 degrees, the jet and the outflow reach their maximum velocities. These observations are compared with the results of the theoretical model and the numerical simulation.