학술논문
Proton inelastic scattering reveals deformation in $^8$He
Document Type
Working Paper
Author
Holl, M.; Kanungo, R.; Sun, Z. H.; Hagen, G.; Lay, J. A.; Moro, A. M.; Navrátil, P.; Papenbrock, T.; Alcorta, M.; Connolly, D.; Davids, B.; Varela, A. Diaz; Gennari, M.; Hackman, G.; Henderson, J.; Ishimoto, S.; Kilic, A. I.; Krücken, R.; Lennarz, A.; Liang, J.; Measures, J.; Mittig, W.; Paetkau, O.; Psaltis, A.; Quaglioni, S.; Randhawa, J. S.; Smallcombe, J.; Thompson, I. J.; Vorabbi, M.; Williams, M.
Source
Phys. Lett. B 822, 136710 (2021)
Subject
Language
Abstract
A measurement of proton inelastic scattering of $^8$He at $8.25A$~MeV at TRIUMF shows a resonance at 3.54(6)~MeV with a width of 0.89(11)~MeV. The energy of the state is in good agreement with coupled cluster and no-core shell model with continuum calculations, with the latter successfully describing the measured resonance width as well. Its differential cross section analyzed with phenomenological collective excitation form factor and microscopic coupled reaction channels framework consistently reveals a large deformation parameter $\beta_2$ = 0.40(3), consistent with no-core shell model predictions of a large neutron deformation. This deformed double-closed shell at the neutron drip-line opens a new paradigm.
Comment: 9 pages, 5 figures. Accepted for publication in Physics Letters B
Comment: 9 pages, 5 figures. Accepted for publication in Physics Letters B