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تسجيل مستخدم جديدProton-proton correlations observed in two-proton decay of $^{19}$Mg and $^{16}$Ne
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Proton-proton correlations were observed for the two-proton decays of the ground states of $^{19}$Mg and $^{16}$Ne. The trajectories of the respective decay products, $^{17}$Ne+p+p and $^{14}$O+p+p, were measured by using a tracking technique with microstrip 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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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 th
e 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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the low-lying states were obtained in a R-matrix analysis of the excitation function. Using these new results, we show that the lifetime of the $^{19}$Mg radioactivity can be understood assuming a sequential emission of two protons via low energy tails of $^{18}$Na resonances.
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
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