Nuclear Structure Features of Gamow-Teller Excitations

Abstract

It is widely accepted that nuclear Gamow-Teller transitions are quenched; shell-model calculations also showed a clear anticorrelation between the Gamow-Teller strength and the transition rate of the collective quadrupole excitation from the ground state. We discuss the physics beyond this observation. It is based on the existence of spin-orbit coupling that is responsible for the non-zero probabilities of Gamow-Teller transitions in self-conjugate nuclei (N = Z). The shell-model calculations in the f p-space demonstrate the effects of the gradual artificial removal of the spin-orbit coupling that influences Gamow-Teller and quadrupole modes in opposite way. The realistic spin-orbit splitting moves the cumulative Gamow-Teller strength up and leads to stronger fragmentation; both trends are discussed in terms of simple symmetry arguments. Along with this process, the Gamow-Teller operator excites, in addition to the main line of L = 0 states, states with L = 2 which should be added, with the interference terms, to account for the total strength.

arXiv comment16 pages, 8 figures

References in corpus (5)

• Determination of the Gamow-Teller Quenching Factor from Charge Exchange Reactions on 90Zr
• Variation with mass of $\boldmath{B(E3; 0_1^+ \to 3_1^-)}$ transition rates in $A=124-134$ even-mass xenon nuclei
• Enhancement of nuclear Schiff moments and time reversal violation in atoms due to soft nuclear octupole vibrations
• Correlation between the quenching of total GT+ strength and the increase of E2 strength
• Nuclear Schiff moment and soft vibrational modes

Cited by in corpus (5)

• Nuclear Equation of State from ground and collective excited state properties of nuclei
• Nuclear charge-exchange excitations based on relativistic density-dependent point-coupling model
• Exact sum rules with approximate ground states
• Nuclear structure studies of double Gamow-Teller strength
• Study of the double Gamow-Teller transitions using the shell model approach