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تسجيل مستخدم جديدProton-proton correlations in distinguishing the two-proton emission mechanism of $^{23}$Al and $^{22}$Mg
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The proton-proton momentum correlation functions ($C_{pp}(q)$) for kinematically complete decay channels of $^{23}$Al $rightarrow$ p + p + $^{21}$Na and $^{22}$Mg $rightarrow$ p + p + $^{20}$Ne have been measured at the RIKEN RI Beam Factory. From the very different correlation strength of $C_{pp}(q)$ for $^{23}$Al and $^{22}$Mg, the source size and emission time information were extracted from the $C_{pp}(q)$ data by assuming a Gaussian source profile in the correlation function calculation code (CRAB). The results indicated that the mechanism of two-proton emission from $^{23}$Al was mainly sequential emission, while that of $^{22}$Mg was mainly three-body simultaneous emission. By combining our earlier results of the two-proton relative momentum and the opening angle, it is pointed out that the mechanism of two-proton emission could be distinguished clearly.
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Two-proton relative momentum ($q_{pp}$) and opening angle ($theta_{pp}$) distributions from the three-body decay of two excited proton-rich nuclei, namely $^{23}$Al $rightarrow$ p + p + $^{21}$Na and $^{22}$Mg $rightarrow$ p + p + $^{20}$Ne, have bee
n measured with the projectile fragment separator (RIPS) at the RIKEN RI Beam Factory. An evident peak at $q_{pp}sim20$ MeV/c as well as a peak in $theta_{pp}$ around 30$^circ$ are seen in the two-proton break-up channel from a highly-excited $^{22}$Mg. In contrast, such peaks are absent for the $^{23}$Al case. It is concluded that the two-proton emission mechanism of excited $^{22}$Mg is quite different from the $^{23}$Al case, with the former having a favorable diproton emission component at a highly excited state and the latter dominated by the sequential decay process.
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crostrip detectors. These data were used to reconstruct the angular correlations of fragments projected on planes transverse to the precursor momenta. The measured three-particle correlations reflect a genuine three-body decay mechanism and allowed us to obtain spectroscopic information on the precursors with valence protons in the $sd$ shell.
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