The Isovector Quadrupole-Quadrupole Interaction Used in Shell Model Calculations
نویسندگان
چکیده
An interaction −χQ ·Q(1+B~τ(1) · ~τ(2)) is used in a shell model calculation for 10Be. Whereas for B = 0 the 21 state is two-fold degenerate, introducing a negative B causes an ‘isovector’ 2+ state to come down to zero energy at B = −0.67 and an S = 1 L = 1 triplet (J = 0+, 1+, 2+) to come down to zero energy at B = −0.73. These are undesirable properties, but a large negative B is apparently needed to fit the energy of the isovector giant quadrupole resonance.
منابع مشابه
The Isovector Quadrupole - Quadrupole Interaction Used in Shell Model Calculations with ∆ N = 2 Excitations
The effect of the " B " term in the interaction −χQ · Q(1 + B τ (1) · τ (2)), which was previously considered in the 0p shell, is now studied in a larger space which includes ∆N = 2 excitations. We still get a collapse of low-lying states below the conventional J = 0 + ground state when B is made sufficiently negative.
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