Surface Localization of the Dineutron in ^{11}Li

Area of Science:

• Nuclear Physics
• Quantum Chromodynamics
• Nuclear Astrophysics

Background:

• The ^{11}Li nucleus is a key subject for studying exotic nuclear structures.
• Understanding dineutron formation provides insights into nuclear forces and matter.

Purpose of the Study:

• To investigate the spatial localization of dineutron formation within the ^{11}Li nucleus.
• To measure the correlation angle between neutrons as a function of momentum.
• To compare experimental data with theoretical models.

Main Methods:

• Utilized the (p,pn) knockout reaction at 246 MeV/nucleon.
• Measured the intrinsic momentum of the struck neutron.
• Analyzed the correlation angle between the two outgoing neutrons.

Main Results:

• Dineutron formation was localized to the surface of the ^{11}Li nucleus at approximately r∼3.6 fm.
• The correlation angle between neutrons was measured for the first time as a function of momentum.
• Experimental results align with theoretical predictions.

Conclusions:

• The dineutron in ^{11}Li is a surface phenomenon.
• Findings support the density dependence of dineutron formation in nuclear matter.
• Experimental data validates Hartree-Fock-Bogoliubov calculations.