Study of n-n correlations in d + 2H --> p + p + n + n reaction

TL;DR

This study experimentally investigates neutron-neutron correlations in a four-body breakup reaction, revealing an enhanced nn-interaction with a low singlet dineutron energy, using kinematically complete measurements at 15 MeV.

Contribution

It provides the first precise measurement of nn-correlation in the d + 2H reaction, indicating an effective nn-interaction enhancement.

Findings

Determined the singlet dineutron energy as 0.076 +/- 0.006 keV.

Observed an effective enhancement of nn-interaction.

Performed a kinematically complete measurement at 15 MeV.

Abstract

A kinematically complete measurement of the four-body breakup reaction d+2H-->2ps+2ns --> p +p +n +n has been performed at 15 MeV deuteron beam of the SINP MSU. The two protons and neutron were detected at angles close to those of emission of 2ps and 2ns systems. The energy of singlet dineutron state was determined by comparing experimental TOF spectrum of breakup neutrons with simulated spectra depending on this energy. A low value Enn = 0.076 +/- 0.006 keV obtained by fitting procedure apparently indicates an effective enhancement of nn-interaction in the intermediate state of studied reaction.