[01] A. Abdel-Hafiez, Department of Experimental Nuclear Physics, Nuclear Research Center, Atomic Energy Authority, Cairo, Egypt. [02] M. E. Medhat, Department of Experimental Nuclear Physics, Nuclear Research Center, Atomic Energy Authority, Cairo, Egypt.

Quantum molecular dynamics (QMD) is used to investigate multifragmentation resulting from an expanding nuclear matter. Equation of state, the structure of nuclear matter and symmetric nuclear matter is discussed. Also, the dependence of the fragment mass distribution on the initial temperature (Tinit) and the radial flow velocity (h) is studied. When h is large, the distribution shows exponential shape, whereas for small h, it obeys exponentially falling distribution. The fragmentation mechanism in an expanding system is found to be different from the one in a thermally equilibrated system. The used Hamiltonian has a classical kinetic energy term and an effective potential term composed of four parts.

Quantum Molecular Dynamics, Expanding Nuclear Matter, Multifragmentation, Fragment Mass Distribution

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