| Authors : | B. Suresh Babu 1, Sudheer K. Mishra 2, Pradeep Kayshap 1, Sharad C. Tripathi 1
1 VIT Bhopal University, Kothari Kalan, Sehore - 466114, Madhya-Pradesh, India.
2 Indian Institute of Astrophysics, Koramangala, Bangalore-560034, India. |
| Abstract : | We have studied the recurring homologous surges using Interface Region Imaging Spectrograph (IRIS) and Solar Dynamic Observatory (SDO) observations. The spectacular active region (AR) 13006 produced 14 homologous surges on May 3rd, 2022, from 19:10 UT to 22:05 UT. All the surges originated from the boundary of AR 13006. The time-distance analysis shows that these surges cover a very broad range of velocities (i.e., 130 to 237 km/s), heights (i.e., 20 to 30 Mm), and lifetimes (i.e., 3 to 10 minutes). To diagnose in-situ physical conditions in these surges, the Si IV spectral lines (i.e., Si IV 1393.78 and Si IV 1402.77) were used. The very complex profiles (i.e., double or multiple peak profiles) are found near the bases of these surges, which justifies the abrupt energy release at the base.
Further, we checked the photospheric magnetic field using HMI observations, and it was found that the base of these surges lies in the mixed polarities. We find that positive flux enhances before the triggering of each surge and further decreases in strength over the lifetime of that particular surge. It seems that there is an indication of flux-cancellation/annihilation. The base of these surges contains strong negative polarity and relatively weak positive polarity. Hence, we say that the magnetic flux-cancellation/annihilation processes may trigger recurring homologous surges. This aspect is further supported by the existence of complex and wide spectral profiles near the bases of surges as there may be abrupt energy release in the flux-cancellation/annihilation. |
