The 106Cd(α, α)106Cd elastic scattering in a wide energy range for γ process studies

Analysis of uncertainties inα-particle optical-potential assessment below the Coulomb barrier

“…An additional support for using these parameters comes from a very recent study of RSFs in the 114 Cd(γ, γ ′ ) and 113 Cd(n, γ) reactions [49] which found similar experimental RSF values for 114 Cd and 112 Cd [31] above 7 MeV. However, it has been found a difference at lower energies which was attributed also to the spin distribution of the states excited through the ( 3 He, 3 He ′ ) and (γ, γ ′ ) processes. Therefore, the RSF data and parameters obtained by the Oslo group [31,32] are particularly suitable for the analysis of (α, γ) reactions.…”

“…Recent high-precision measurements [1][2][3][4][5][6] of α-particle induced reaction data below the Coulomb barrier (B) provide an useful opportunity to investigate the results of a previous optical-model potential (OMP) for α-particles on nuclei within the mass number range 45≤A≤209 [7]. Actually, this potential was established by (1) analysis of α-particle elastic-scattering angular distributions above B [7,8], and (2) Hauser-Feshbach statistical model (SM) assessment of the available (α, γ), (α, n) and (α, p) reaction cross sections for incident energies below B and target nuclei either with A≤120 [9] or heavier [7,10].…”

“…So, it was possible to reproduce simultaneously the data for 107 Ag only by rescaling the ratio of γ to neutron widths [2]. A study of both elastic-scattering and α-induced reaction cross sections for 106 Cd at low energies concluded as well that these data allow to constrain the other SM ingredients except the α-particle OMP [3]. Total and for the first-time measured partial cross sections of the (α, γ) reaction, for 112 Sn target nucleus, pointed out a disagreement between experiment and theory which was considered to be most probably a deficiency of the nuclear-physics input [4].…”

“…Moreover, it has been considered an yet open question [2,3,5,6] whether this modification is due to a required OMP change, which affects the total-reaction cross section, or due to the ne-glection of the Coulomb excitation (CE) in the entrance channel [17]. All these new measured data and related α-particle OMP studies within so different mass ranges motivated the present work, with the aim to both check the applicability of the previous OMP [7] and to look for uncertainties and possible systematic errors of α-particle optical-potential assessment at low energies.…”

“…The results corresponding to the OMP of Ref. [7] are then compared with the recently measured cross sections [1][2][3][4][5][6] in Sec. III, followed by conclusions in Sec.…”