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تسجيل مستخدم جديدStudy of multi-neutron emission in the $beta$-decay of $^{11}$Li
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The kinematics of two-neutron emission following the $beta$-decay of $^{11}$Li was investigated for the first time by detecting the two neutrons in coincidence and by measuring their angle and energy. An array of liquid-scintillator neutron detectors was used to reject cosmic-ray and $gamma$-ray backgrounds by pulse-shape discrimination. Cross-talk events in which two detectors are fired by a single neutron were rejected using a filter tested on the $beta$-1n emitter $^9$Li. A large cross-talk rejection rate is obtained ($> 95 %$) over most of the energy range of interest. Application to $^{11}$Li data leads to a significant number of events interpreted as $beta$-2n decay. A discrete neutron line at $approx$ 2 MeV indicates sequential two-neutron emission, possibly from the unbound state at 10.6 MeV excitation energy in $^{11}$Be.
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Coincidences between charged particles emitted in the $beta$-decay of $^{11}$Li were observed using highly segmented detectors. The breakup channels involving three particles were studied in full kinematics allowing for the reconstruction of the exci
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The neutron-rich $^{11}$Li halo nucleus is unique among nuclei with known separation energies by its ability to emit a proton and a neutron in a $beta$ decay process. The branching ratio towards this rare decay mode is evaluated within a three-body m
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The formation of a dineutron in the nucleus $^{11}$Li is found to be localized to the surface region. The experiment measured the intrinsic momentum of the struck neutron in $^{11}$Li via the $(p,pn)$ knockout reaction at 246 MeV/nucleon. The correla
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