We have calculated the potential energy surfaces for 240Pu up to the scission point using the density functional theory with different pairing strengths to investigate the effect of pairing correlations on its fission properties. An enhancement in the pairing correlations lowers the barrier heights, isomeric state, and ridge between the symmetric and asymmetric fission valleys significantly. Moreover, it weakens the microscopic shell structure around the Fermi surface, shrinks the scission frontiers, especially for the symmetric and very asymmetric fission regions, and lifts the total kinetic energies (TKEs) for the symmetric fission region. It is also emphasized that the microscopic calculation qualitatively reproduces the trend of the distribution of the measured TKEs, especially for the positions of the peaks at and .

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Magnetic reconnection (MR) is a universal physical process in plasma, in which the stored magnetic energy is converted into high-velocity flows and energetic particles. It is believed that MR plays an important role in many plasma phenomena such as solar fare, gamma-ray burst, fusion plasma instabilities, etc.. The process of MR has been studied in detail by dedicated magnetic-driven experiments. Here, we report the measurements of magnetic reconnection driven by Shenguang II lasers and Gekko XVII lasers. A collimated plasma jet is observed along the direction perpendicular to the reconnection plane with the optical probing. The present jet is very different from traditional magnetic reconnection outflows as known in the two-dimensional reconnection plane. In our experiment, by changing the delay of optical probing beam, we measure the temporal evolution of jet from 0.5 ns to 2.5 ns and its velocity around 400 km/s is deduced. Highcollimated jet is also confirmed by its strong X-ray radiation recorded by an X-ray pinhole camera. With the help of optical interferograms we calculate the jet configuration and its density distribution by using Abel inverting technique. A magnetic spectrometer with an energy range from hundred eV up to one MeV is installed in front of the jet, in the direction perpendicular to the reconnection plane, to measure the accelerated electrons. Two cases are considered for checking the acceleration of electrons. The results show that more accelerated electrons can be found in the reconnection case than in the case without reconnection. We propose that the formation and collimation of the plasma jet, and the electron energy spectrum may be possible directly influenced by the reconnection electric field, which is very important for understanding the energy conversion in the process of MR and establishment of the theoretical model. Finally the electron energy spectra of three different materials Al, Ta and Au are also shown in our work. The results indicate that the higher atomic number material can obtain a better signal-noise ratio, which provides some helpful references for our future work.