Energy levels of light nuclei

The Trojan Horse Method application on the 10B(p,α0)7Be reaction cross section measurements

“…The 2 H( 10 B,α 0 7 Be)n excitation function has been extracted in an energy range from 3 keV to 2.2 MeV. For the experimental energy resolution, evaluated from FWHMs of the 11 C levels at energies of 8.654 MeV (E cm =-35 keV) and 8.699 MeV (E cm =10 keV) [22], was found to be δ =17±1 keV. This is notable improvement compared to the previous THM experiments on the same reaction, where the experimental resolution was found to be 31±3 keV in [15] and 87±5 keV in [16].…”

Beta decay to continuum states: the case of11Be

“…The two-neutron halo nuclei 6 He and 11 Li appear both to have beta-delayed deuteron emission taking place directly into the continuum [1,6]. For 11 Li this process has a branching ratio of the order of 10 −4 , the low value mainly being due to the small energy window, whereas cancellation effects reduces the branching ratio for 6 He down to the 10 −6 level. The simple-minded model of the decays is that one of the two halo neutrons beta-decay into a proton and combines with the other one to form a deuteron.…”

Measurement of the B10(p,α0)Be7 cross section from 5 keV to 1.5 MeV

“…9.645±50 956 (3/2 − ) 210±40 (γ,p,α) [9] (8) 9.780±50 1091 (5/2 − ) 240±50 (γ,p) [25] (9) 9.970±50 1281 (7/2 − ) 120±20 (γ,p) [25] (10) 10.083±5 1394 7/2 + ∼230 (γ,p,α) [25] The observed peak corresponding to the two unresolved levels (3)+(4) has been fitted by considering the broadening due to the energy resolution. The fitting function is expressed in terms of the incoherent sum of two Breit-Wigner shapes bw(E) (3) , bw(E) (4) , plus an additional term describing the contribution of the tail of the resonant level at 9.2 MeV, bw(E) (5) , and a non resonant term p(E):…”

“…However, the 10 B(p,α 0 ) 7 Be cross section was measured in the energy range 0-100 keV [16], and the lack of a sufficient statistics did not allow us to extend the excitation function in the region 100 -1000 keV. Normalization was then performed by matching the THM Sfactor to a R-matrix calculation performed by introducing into the calculation the resonance parameters from the literature [25], and caused the measured S(E)-factor to be affected by an uncertainty of 20% mainly due to the normalization procedure [16].…”