Photoneutron cross sections for neodymium isotopes: Toward a unified understanding of(γ,n)and(n,γ)reactions in the rare earth region

Abstract

Photoneutron cross sections were measured for five stable Nd isotopes, 143,144,145,146,148 Nd, near neutron threshold with highly monochromatic laser-Compton scattering γ rays. The photoneutron data were compared with the calculations performed with the TALYS reaction code with inputs of the Skyrme Hartree-Fock-Bogoliubov (HFB) plus quasi-particle random phase approximation (QRPA) model and the axially symmetric deformed Gogny HFB plus QRPA model of E1 γ -ray strength. Using the γ -ray strength function constrained by the present photoneutron data, a thorough analysis of the reverse (n,γ ) cross sections is made. Radiative neutron capture cross sections for an s-process branching-point nucleus in the rare earth region, 147 Nd with the half-life 10.98 d, are deduced with the γ -ray strength function method. The impact of the newly evaluated 147 Nd(n,γ ) 148 Nd cross section on s-process nucleosynthesis is discussed.

Photodisintegration ofBe9through the1/2+state and cluster dipole resonance

“…The efficiencies were calibrated with a 252 Cf source at the National Metrology Institute of Japan (NMIJ). The detector has long been used for (γ , n) cross section measurements for heavy nuclei (see [24,25] for the latest measurements and references therein). The detection efficiencies were recalibrated in advance to the present experiment using a 252 Cf source at a neutron emission rate 2.27 × 10 4 s −1 with 2.2% uncertainty at the NMIJ.…”

Production cross sections of products in the proton induced reactions on natNd in the energy region up to 45 MeV

“…There are some experiments, which were carried out for measuring the cross sections of reactions on Nd with various particles [6][7][8][9][10][11][12][13]. However, the production cross sections of the nat Nd(p,x) reaction were measured only by Lebeda et al [7,8] and Petzoldt [9].…”

Dipole strength inSe80forsprocess and nuclear transmutation ofSe79

“…In the past half century, the giant dipole resonance (GDR) has been investigated both experimentally and theoretically via photonuclear reactions by many researchers [1,2]. Nowadays, more precise measurements of photoneutron reactions near the neutron threshold (S n ) are performed by using quasimonochromatic γ rays [3][4][5][6]. The low-energy tail of the GDR below S n is of particular interest because of an extra enhancement of observed E1 strength.…”