2,748 research outputs found
Dissipative tunneling through a parabolic potential in the Lindblad theory of open quantum systems
By using the Lindblad theory for open quantum systems, an analytical
expression of the tunneling probability through an inverted parabola is
obtained. This penetration probability depends on the environment coefficients.
It is shown that the tunneling probability increases with the dissipation and
the temperature of the thermal bath.Comment: 16 pages, 6 figure
Phase Space Representation for Open Quantum Systems within the Lindblad Theory
The Lindblad master equation for an open quantum system with a Hamiltonian
containing an arbitrary potential is written as an equation for the Wigner
distribution function in the phase space representation. The time derivative of
this function is given by a sum of three parts: the classical one, the quantum
corrections and the contribution due to the opening of the system. In the
particular case of a harmonic oscillator, quantum corrections do not exist.Comment: 19 pages, Latex, accepted for publication in Int. J. Mod. Phys.
Systematics of fusion probability in "hot" fusion reactions
The fusion probability in "hot" fusion reactions leading to the synthesis of
super-heavy nuclei is investigated systematically. The quasi-fission barrier
influences the formation of the super-heavy nucleus around the "island of
stability" in addition to the shell correction. Based on the quasi-fission
barrier height obtained with the Skyrme energy-density functional, we propose
an analytical expression for the description of the fusion probability, with
which the measured evaporation residual cross sections can be reproduced
acceptably well. Simultaneously, some special fusion reactions for synthesizing
new elements 119 and 120 are studied. The predicted evaporation residual cross
sections for 50Ti+249Bk are about 10-150fb at energies around the
entrance-channel Coulomb barrier. For the fusion reactions synthesizing element
120 with projectiles 54Cr and 58Fe, the cross sections fall to a few femtobarns
which seems beyond the limit of the available facilities.Comment: 5 figures, 1 tabl
- …