Javid A. Sheikh

Cranked shell model and isospin symmetry near N = Z

Abstract A cranked shell model approach for the description of rotational bands in N ≈ Z nuclei is formulated. The isovector neutron-proton pairing is taken into account explicitly. The concept of spontaneous breaking and subsequent restoration of the isospin symmetry turns out to be crucial. The general rules to construct the near yrast spectra for rotating nuclei are presented. For the model case of particles in a j-shell, it is shown that excitation spectra and the alignment processes are well described as compared to the exact shell model calculation. Realistic cranked shell model calculations are able to describe the experimental spectra of 72,73 Kr and 74 Rb isotopes.

Symmetry-projected Hartree–Fock–Bogoliubov equations

Abstract Symmetry-projected Hartree–Fock–Bogoliubov (HFB) equations are derived using the variational ansatz for the generalized one-body density matrix in the Valatin form. It is shown that the projected-energy functional can be completely expressed in terms of the HFB density matrix and the pairing-tensor. The variation of this projected energy is shown to result in HFB equations with modified expressions for the pairing-potential Δ and the Hartree–Fock field Γ . The expressions for these quantities are explicitly derived for the case of particle number projection. The numerical applicability of this projection method is studied in an exactly soluble model of a deformed single-j shell.

Projected shell model study for the yrast - band structure of the proton rich mass 80 nuclei

Abstract A systematic study of the yrast-band structure for the proton-rich, even–even mass-80 nuclei is carried out using the projected shell model approach. We describe the energy spectra, transition quadrupole moments and gyromagnetic factors. The observed variations in energy spectra and transition quadrupole moments in this mass region are discussed in terms of the configuration mixing of the projected deformed Nilsson states as a function of shell filling.

Multiphonon gamma vibrational bands and the triaxial projected shell model

We present a fully quantum-mechanical, microscopic, unified treatment of ground-state band and multi-phonon

Pairing correlations and particle-number projection methods

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Anomalous rotational alignment in N=Z nuclei and residual neutron proton interaction

-vibrational bands using shell model diagonalization with the triaxial projected shell model. The results agree very well with data on the g- and

Projected shell model study of odd-oddf−p−gshell proton-rich nuclei

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γ-vibrational states in superheavy nuclei

-band spectra in

Mixing of quasiparticle excitations and

^{156-170}

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Er, as well as with recently measured