Small oscillations in a nuclear Vlasov fluid
Tóm tắt
We present a semi-classical approach to the dynamics of nuclear collective motions. We study a linearized version of the nuclear Vlasov equation, obtained from a phase-space representation of a meanfield theory, which corresponds to a semi-classical version of the RPA approach. Giant resonances are shown to be quite well described as scaling modes, which are equivalent to a lowest multipole (up tol
max=2) distortion of the momentum distributions. We present detailed results for isoscalar-giant-quadrupole and isovector-giant-dipole modes. We discuss various sources of damping giving some suggestions for the study of the Landau damping in a nuclear system, in competition with explicit two-body collision terms.
Tài liệu tham khảo
P. Ring andP. Schuck:The Nuclear Many Body Problem (Springer-Verlag, Berlin, 1980).
D. M. Brink andM. Di Toro:Nucl. Phys. A,372, 151 (1981).
M. Di Toro:Nuclear Dynamics in Phase Space, Lectures delivered at the “Winter College on Fundamental Nuclear Physics”, ICTP, Trieste 1984 and preprint GANIL 84-07.
S. E. Koonin:Prog. Part. Nucl. Phys.,4, 283 (1980).
M. Collins andJ. J. Griffin:Nucl. Phys. A,348, 63 (1980).
G. Bertsch:Z. Phys. A,289, 103 (1978).
P. Quentin andH. Flocard:Annu. Rev. Nucl. Sci.,28, 523 (1978).
Y. M. Engel, D. M. Brink, K. Goeke andD. Vautherin:Nucl. Phys. A,249, 215 (1975).
M. Di Nardo, M. Di Toro, G. Giansiracusa, U. Lombardo andG. Russo:Phys. Rev. C,28, 929 (1983).
H. H. K. Tang, C. H. Dasso, H. Esbensen, R. A. Broglia andA. Winther:Phys. Lett. B,101, 10 (1981).
W. Nörenberg:Nucl. Phys. A,409, 191C (1983).
M. Di Nardo, M. Di Toro, G. Giansiracusa, U. Lombardo andG. Russo:Lett. Nuovo Cimento,35, 113 (1982).
M. J. Giannoni andP. Quentin:Phys. Rev. C,21, 2060, 2076 (1980).
K. Ando andS. Nishizaki:Prog. Theory. Phys.,68, 1196 (1982).
F. E. Bertrand:Proceedings of Nuclear Heavy Ion Collisions, inProc. S.I.F., Course LXXVII (Bologna, 1981).
G. Eckart:J. Phys. (Paris) C,6, 285 (1984).
M. Di Toro, G. Giansiracusa, U. Lombardo andG. Russo:J. Phys. (Paris) C,4, 297 (1984).
A. Bonaccorso, M. Di Toro, U. Lombardo andG. Russo:J. Phys. (Paris) C,6, 269 (1984).
J. P. Da Providência andG. Holzwarth:Nucl. Phys. A,398, 59 (1983).
E. A. Uehling andG. E. Uhlenbeck:Phys. Rev.,43, 552 (1933).
S. Stringari: this issue, p. 231.