Proton and Two-proton Emissions from Proton-rich Nuclei with 10 ≤ Z ≤ 20

Proton(p) and two-proton(2p) emissions from the proton-rich nuclei with 10≤Z≤20 have been explored by the in-fight decay and implantation decay methods, respectively, in a series of experiments at the HIRFL-RIBLL facility. The in-flight 2p emissions from the excited states of ^(28,29)S/^(26,27)P and ^(17,18)Ne were studied by complete-kinematics measurements. Mechanisms of 2p decay and related p-p correlations have been explored. Obvious 2p correlated emissions have been observed in the cases of ^(28,29)S but not in ^(27,28)P, indicating the 2p halo plays an important role in the diproton emission. In the ^(17,18)Ne cases, a small 2p opening angles were deduced by the HBT analyses, implying the BCS-BEC crossover may occur in the dilute nuclear matter. Moreover,^(27)S/^(26)P/^(25)Si,^(22)Si/^(20)Mg,^(23)Si/^(22)Al/^(21)Mg,^(24)Si/^(23)Al, and ^(36,37)Ca were implanted in a thin double-sided-silicon-strip detector and their β-delayed p and 2p decays have been measured by a surrounding silicon detector array under the continuous-beam mode. Important information on the nuclear spectroscopy, such as energy, lifetime, branching-ratio, and so on, has been extracted, which helps us to understand the nuclear structures of proton-rich exotic nuclei close to the drip-line.

Proton （p） and two-proton （2p） emissions from the proton-rich nuclei with 10≤ Z ≤ 20 have been explored by the in-fight decay and implantation decay methods, respectively, in a series of experi- ments at the HIRFL-RIBLL facility. The in-flight 2p emissions from the excited states of 2s＇29S/26＇27P and 17＇ZSNe were studied by complete-kinematics measurements. Mechanisms of 2p decay and related p-p correlations have been explored. Obvious 2p correlated emissions have been observed in the cases of 2s＇29S but not in 27,28p, indicating the 2p halo plays an important role in the diproton emission. In the 17＇lSNe cases, a small 2p opening angles were deduced by the HBT analyses, implying the BCS-BEC crossover may occur in the dilute nuclear matter. Moreover, 27S/26p/25Si, 228i/20Mg, 238i/22Al/21Mg, 24Si/23A1, and 36,37Ca were implanted in a thin double-sided-silicon-strip detector and their β-delayed p and 2p decays have been measured by a surrounding silicon detector array under the continuous-beam mode. Important information on the nuclear spectroscopy, such as energy, lifetime, branching-ratio, and so on, has been extracted, which helps us to understand the nuclear structures of proton-rich exotic nuclei close to the drip-line.