Mass dependence of the surface δ-interaction strength for two-particle (two-hole) multiplets

Abstract

Abstract. By using the surface δ-interaction, the lowest states in nuclei of atomic mass number 6 ≤ A ≤ 210 with a doubly magic core and two valence nucleons are investigated. A single parameter describes the strength of the multiplet splitting of the lowest configuration which includes the ground state. The dependence of the strength on the atomic mass number of the doubly magic core is determined as a power law function A −f with an exponent f =

Structure of negative parity states at $${\mathbf {6}\,\lesssim \, \mathbf {E}_\mathbf {x} <{\mathbf {7.0}} }$$ MeV in $$\mathbf {^{208}}{} \mathbf{Pb}$$

“…∼ E x < 7.0 MeV SM calculations using the SDI [15] predict the multiplet splitting of 1p1h configurations. It also explains the ground state of even-even nuclei to have spin 0 + because of the large down shift in the multiplet splitting with two nucleons in the same orbit [15,16].…”

“…Figures 22, 23 show some spectra. In contrast to the simple triangle method [40] the advanced features of GASPAN were used to fit the contamination peaks from 12 C(p, p ), 16 O(p, p ), 208 Pb(p, d), and 208 Pb(p, t) with different peak widths. By this manner more levels of 208 Pb could be resolved in the neighborhood of the contaminations than found by Glöckner [39].…”

“…The surface delta interaction (SDI) was introduced by Green and Moszkowski [14] and extensively discussed by Talmi [15]. It provides a simple method to understand the interaction among two particles in a complex nucleus [2,[15][16][17][18].…”

“…References s 1/2 16.965 [28] 319 [28] 16.496 [28] 303 [28] g 7/2 17.400 b 288 [28] g 9/2 14.918 [28] 253 [28] i 11/2 15.716 [28] 224 [28] j 15/2 16.375 [45] 210 [28] (3 − ⊗ g 9/2 ) 16.600 [50] (300) [50] a Change from 17.476 [28], see Sect. 3.3.5 b Change from 17.430 [28], see Sect.…”

Pairing and (9/2)n configuration in nuclei in the 208Pb region

“…Since the values of V 0 and F 0 (nl) do not depend on J, the structure of the GSM can be determined from the ratio of the energies of levels with different values of J, to the known experimental value of the excitation energy, for example, E(2 + ) [9] or E(J max ), where J max = 2 j − 1 [10]. However, the GSM structure can be calculated using the ground state energy shift ∆E 0 , defined by the even-odd staggering effect: ∆E 0 = ∆ nn(pp) = 2∆ n(p) [11].…”