Tetraneutron Resonance: Theory

We continue the study of the tetraneutron resonance within the democratic SS-HORSE extension of the ab initio No Core Shell Model using modern NN interactions. With Daejeon16 and SRG-evolved chiral Idaho N3LO NN interactions we obtain the S-matrix pole corresponding to the tetraneutron resonance with energy between 0.7 and 1.0 MeV and width between 1.1 and 1.7 MeV. However we do not obtain a low-lying narrow resonance with the original Idaho N3LO but, instead, we obtain a very low-lying virtual state with the energy of 15 keV.