X iv : n uc l - th / 9 50 10 28 v 1 2 6 Ja n 19 95 Pseudo - Spin Symmetry and its Applications

ar X iv : n uc l - th / 9 50 10 30 v 1 2 6 Ja n 19 95 Double beta decay in heavy deformed nuclei : what have we learned ?

The pseudo SU(3) approach is used to describe low lying states and BE(2) intensities of rare earth and actinide nuclei which are ββ decay candidates. The ββ half lives of some of these nuclei to the ground and excited states of the final ones are evaluated for both the two and zero neutrino emitting modes. The existence of selection rules which strongly restricts the decays is discussed. These ...

ar X iv : n uc l - th / 0 20 10 61 v 1 2 3 Ja n 20 02 Boson - conserving one - nucleon transfer operator in the interacting boson model

The boson-conserving one-nucleon transfer operator in the interacting boson model (IBA) is reanalyzed. Extra terms are added to the usual form used for that operator. These new terms change generalized seniority by one unit, as the ones considered up to now. The results obtained using the new form for the transfer operator are compared with those obtained with the traditional form in a simple c...

ar X iv : n uc l - th / 0 00 10 36 v 1 1 9 Ja n 20 00 F - spin as a Partial Symmetry

We use the empirical evidence that F-spin multiplets exist in nuclei for only selected states as an indication that F-spin can be regarded as a partial symmetry. We show that there is a class of non-F-scalar IBM-2 Hamiltonians with partial F-spin symmetry, which reproduce the known systematics of collective bands in nuclei. These Hamiltonians predict that the scissors states have good F-spin an...

X iv : n uc l - th / 9 50 20 43 v 1 2 5 Fe b 19 95 1 / N expansion formalism for high - spin states

The 1/N expansion solutions for the interacting boson model are extended to higher orders using computer algebra. The analytic results are compared with those obtained from an exact diagonalization of the Hamiltonian and are shown to be very accurate. The extended formulas for level energies and E2 transitions will be useful in the analysis of high-spin states in both normal and superdeformed n...

ar X iv : n uc l - th / 9 90 10 97 v 1 2 9 Ja n 19 99 1 The Landau - Migdal Parameters , g ′ NN and g