Structure of8B from elastic and inelastic7Be+pscattering

Abstract

Background: Detailed experimental knowledge of the level structure of light weakly bound nuclei is necessary to guide the development of new theoretical approaches that combine nuclear structure with reaction dynamics.Purpose: The resonant structure of 8 B is studied in this work.Method: Excitation functions for elastic and inelastic 7 Be+p scattering were measured using a 7 Be rare isotope beam. Excitation energies ranging between 1.6 and 3.4 MeV were investigated.An R-matrix analysis of the excitation functions was performed. Conclusions: Identification of the 0 + , 2 + , 1 + states that were predicted by some models at relatively low energy but never observed experimentally is an important step toward understanding the structure of 8 B. Their identification was aided by having both elastic and inelastic scattering data. Direct comparison of the cross sections and phase shifts predicted by the TDCSM and ab initio No Core Shell Model coupled with the resonating group method is of particular interest and provides a good test for these theoretical approaches.

Proton-decaying states in light nuclei and the first observation of Na17

“…By fitting both peaks in the excitation-energy spectrum and extracting the areas (with uncertainties dominated by background contributions), and correcting for the detector efficiency (20.5 % and 24.9 % respectively), the branching ratio was found to be 1.1 ± 0.3 % to the 1/2 + excited state and 98.9 ± 1.8 % to the 3/2 + ground state of 7 Be. The partial proton width for decay to the ground state was measured in proton scattering on 7 Be [26], with a value of Γ p = 0.026 (6) MeV. Comparing this to the total width, Γ tot = 0.027 (6) MeV, yields a branching ratio to the ground state of 96 ± 30 % in agreement with the present result but with much larger uncertainty.…”

s -wave scattering lengths for the Be7+p system from an R -matrix analysis

“…The 0 + level at an excitation energy of 1.9 MeV in 8 B was previously suggested in Ref. [17]. The 1 − level is introduced as a background level in our fits.…”

“…The sensitivity of the fit to the excitation energy of the 2 + level was studied and we differ in the extracted excitation energy for such a level from Ref. [17].…”

Microscopic Description of 8Li and 8B Nuclei within a Three-Cluster Model

“…Properties of mirror nuclei 8 Li and 8 B have been intensively investigated in microscopic [5][6][7][8][9][10][11][12][13][14] and semimicroscopic models [15][16][17][18][19]. In addition, different experimental methods [20][21][22][23][24][25][26][27][28][29][30] were used to determine the structures of 8 Li and 8 and nuclear reactions in these nuclei. In particular, new resonance states of 8 B have been recently discovered in [24,28] in the elastic 7 Be + p scattering.…”

“…In addition, different experimental methods [20][21][22][23][24][25][26][27][28][29][30] were used to determine the structures of 8 Li and 8 and nuclear reactions in these nuclei. In particular, new resonance states of 8 B have been recently discovered in [24,28] in the elastic 7 Be + p scattering.…”