Colour superconductivity in finite systems

We have studied the effects of finite size on the two flavor colour superconducting state. Since the baryon number in the BCS state is only fixed on average, we have projected the state onto a fixed baryon number. The resulting state has been then projected onto a colour-singlet state, by integrating onto the colour group manifold. The effects of both projections have been evaluated numerically.     

Algebraic approaches in nuclear physics

In these lectures I discuss algebraic approaches in nuclear physics. The emphasis is on aspects that can not be found in the same form in other publications of the subject. We discuss the relation between bosons and fermions, as well as some of the standard formalism underlying all algebraic models in nuclear physics. We then contrast fermionic and bosonic models. We end with a case study on supersymmetry in superdeformed nuclei. Dedicated to the memory of Prof. P.W.M. Glaudemans, 1931–1998. Lecture given at the 10th Indian-Summer School of Nuclear Physics: “Theory of Many-Fermion Systems”, Prague, September 8–12, 1997.     

Large amplitude collective motion in nuclei and metallic clusters — Applicability of adiabatic theory for a pairing model

A model Hamiltonian describing a two-level system with a crossing plus a pairing force is investigated using the technique of large-amplitude collective motion. The collective path, which is determined by the decoupling conditions, is found to be almost identical to the one in the Born-Oppenheimer approximation for the case of a strong pairing force. For the weak pairing case, the obtained path describes a diabatic dynamics of the system. Presented by T. Nakatsukasa at the International Conference on “Atomic Nuclei and Metallic Clusters”, Prague, September 1–5, 1997. This work is supported by EPSRC (UK).     

Algebraic approaches in nuclear physics

I critically discuss the various algebraic approaches in nuclear physics, looking for limitations and successes. Special emphasis is placed on open problems and active research areas. Presented at the International Conference on “Atomic Nuclei and Metallic Clusters”, Prague, September 1–5, 1997.     

Steady vortical flow around a finite plate

An explicit solution for a layer of fluid with constant vorticitysurrounding a thin plate of finite length is obtained usingelementary conformal mapping methods. In the limit of largeplate length the behaviour of the solution near the ends ofthe plate tends to that of the previously known solution fora semi-infinite plate. Contour dynamics is used to investigatethe stability of the steady solutions.     

Extracting nuclear transparency from p,2p-A and e,e′p-A cross sections

We study nuclear-structure effects on the transparency in high-transverse-momentum (p,2p) and (e,e′p) reactions. We show that in the eikonal-distorted-wave impulse approximation (EDWIA), even when correlations are included, one can get a factorized expression for the transparency which depends only on the average nucleon density (r) and a correlation function. A technique is developed to include correlations in a Glauber calculation, where we use a Monte Carlo method for integration over the nuclear coordinates. We compare calculations of T using the EDWIA formalism, and a continuous density, with a Monte Carlo method based on discrete nucleons.