Indications for the nonexistence of three-neutron resonances near the physical region

Abstract

The pending question of the existence of three-neutron resonances near the physical energy region is reconsidered. Finite rank neutron-neutron forces are used in Faddeev equations, which are analytically continued into the unphysical energy sheet below the positive real energy axis. The trajectories of the three-neutron S-matrix poles in the states of total angular momenta and parity J π = 1 2 ± and J π = 3 2 ± are traced out as a function of artificial enhancement factors of the neutron-neutron forces. The final positions of the S-matrix poles removing the artificial factors are found in all cases to be far away from the positive real energy axis, which provides a strong indication for the nonexistence of nearby three-neutron resonances. The pole trajectories close to the threshold E = 0 are also predicted out of auxiliary generated three-neutron bound state energies using the Padé method and agree very well with the directly calculated ones.

Three-neutron resonance study using transition operators

“…This fact strongly suggests the absence of physically observable 3n resonance in the J Π = 3 2 − state, confirming the conclusions of Refs. [6,7].…”

SHARAQ spectrometer and GRAPE

“…These systems are also interesting from the point of views of the limits of the nuclear system beyond the neutron dripline especially for correlations in multi-body scattering states. Missing mass spectroscopy of the multi-neutron system via exothermic double charge exchange reactions with minimum momentum transfers of 10-20 MeV/c is a unique tool for experimental studies, which can be directly compared to theoretical predictions of the spectra by using realistic N-N interactions [9,10]. This idea can be extended to the study of very neutron-rich ''superheavy" hydrogen systems, 6,7 H, which are also unique multi-body scattering states.…”

Complete set of polarization transfer coefficients for the3He(p,n)reaction at 346 MeV and 0 degrees

“…The final states with J π = 1/2 ± and 3/2 ± were investigated [5]. The one-body density matrix elements for the transitions to these states by 3 He(p, n) were obtained with the shell-model (SM) code oxbash [29].…”

“…Recently three-neutron T = 3/2 resonances have been studied in the framework of configuration-space Faddeev equations [4,5]. Unfortunately, these studies have indicated the absence of three-neutron resonances.…”