A unified model calculation of states in odd-mass technetium isotopes

Abstract

States in 93'95'97'99'1~ are studied in a unified model calculation without any adjustable parameters except the excitation energy of the first 1/2-state. The positive parity states are described as a mixture of (pl/2)Z(g9/2) 3 and (pl/2)~ 5 proton configurations coupled to a core undergoing quadrupole oscillations. For the negative parity states a proton quasi-particle in the Pl/2, P3/2 and f5/2 orbits is coupled to the vibrations.Calculated energies and electromagnetic moments agree quite well with available data.

Absolute transition probabilities from the 53.2 keV level in105Ag

“…This resembles what has been found in odd mass Tc isotopes where protons rather than neutrons occupies the lg9/z orbit [1]. Furthermore, the E2 transition probabilities between the low lying positive parity states have experimentally been found to be more enhanced than expected from shell model calculations [2].…”

High-spin states in97Tc

“…--.17/2 + 1,349.1 (1) 36 (1) --, 13/2 + 1,363.0(2) ~ 7/2 + 1,393.5 (1) 94 (3) 13/2 + ~ 9/2 + 0.26(2) -0.05(3) 0.70 (7) b Doublet: intensities, and coefficients are given for the sum of both lines ~ Doublet with unidentified line d Intensity derived from the coincidence measurement…”

“…It should be possible to study multiparticle configurations j" and get valuable information about residual interactions by means of these isotopes. In the Alaga-Paar model [1] the odd-A Tc-isotopes are described by coupling a three particle valence-shell cluster to quadrupole vibrations of the core. Bhatt and Ball [2] and Vervier [3] calculated the levelstructure of Tc-isotopes with mass number A>95 utilizing effective interaction matrix elements obtained from experiments.…”

Core vibration of99Tc

“…(5) Detailed theoretical investigations of the microscopic structure of 99Tc have been performed in the past [13,14]. These calculations succeeded to reproduce fairly well the excitation energies of the multiplet and the measured B (E2 ll) values.…”

“…Bargholtz and Beshai [ 14] extended therefore for the odd A technetium isotopes these model calculations by clustering up to five valence )2 3 nucleons, (protons) i.e., (Pl/2 (g9/2) and (pl/2) ~ (g9/2) 5 and by coupling these clusters to the vibrations of the even-even core by quadrupole-quadrupole coupling. Bargholtz and Beshai [ 14] extended therefore for the odd A technetium isotopes these model calculations by clustering up to five valence )2 3 nucleons, (protons) i.e., (Pl/2 (g9/2) and (pl/2) ~ (g9/2) 5 and by coupling these clusters to the vibrations of the even-even core by quadrupole-quadrupole coupling.…”