Extended interacting boson model with configuration mixing description for 98Mo

An extended version of the interacting boson model (IBM), encompassing two-particle-two-hole (2p-2h) excitations originating from below a valence shell and one-particle-one-hole (1p-1h) excitations extending to the upper next-nearest major shell, is developed to investigate cross-shell excitation effects in the transitional nucleus 98Mo. This extended IBM framework is utilized to reproduce experimentally observed properties such as low-lying positive-parity level energies, B(E2) values, and the electric quadrupole moment of the 2+1 state, p2(E0, 0+2 -> 0+g ), as well as the strength functions of the isoscalar giant monopole resonance (ISGMR) and the isoscalar giant quadrupole resonance (ISGQR) in 98Mo. It is shown that the extended consistent-Q IBM, incorporating configuration mixing of both 2p-2h excitations from below the valence shell and 1p-1h excitations to the upper next-nearest major shell, describes the low-lying structural properties and the ISGMR and ISGQR strength distributions of 98Mo quite well, with the ISGMR and the ISGQR strength distributions comparable to the results of the self-consistent quasiparticle random-phase approximation with Skyrme interactions.