Asymmetry of velocity distributions in peripheral reactions with heavy ions at Fermi energies

Abstract

Оставшаяся диссипативная (глубоко-неупругая) компонента хорошо описыва-ется в рамках примененного нами подхода. Показано, что отношение сечений прямой и диссипативной компонент, определяющее асимметрию скоростных распределений, зависит от формы функции отклонения фрагментов относитель-но оси пучка.

Radioactive nuclear beams of COMBAS facility

“…The measurements of total reaction cross sections σ R for weakly bound 6,8 He and 8,9 Li on the nat Al and nat Pb targets at energies (15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30)(31)(32)(33) MeV/A were per formed and the results were compared with the previ ous experiments [36,37]. In the range of 10% accu racy there is an agreement with known data.…”

“…The momentum acceptance of the separator containing the Al degrader at intermediate focus F d must not exceed 2%. The trajectory analysis of the secondary 27 F, 29 F, 28 Ne, and 30 Ne beams (ahead of the second target) is carried out by a tracking detector which is necessary to determine the angular divergence and the size of the beam on the 12 C target at focus F a2 (Fig. 2).…”

“…In the experiments over the elastic scattering, it is planned to study an evolution of the nucleus shape of unstable nuclei with an increase in the neutron excess for isotopes near N = 20 shell closure, namely, heavy isotopes of elements Ne, [23][24][25][26][27][28][29][30][31][32] Na and Al [42].…”

“…Using known present theoretical approaches the direct component was optimal interpreted in the framework of the Goldhaber model [21] and the dissi pative component was analyzed using of the two mod els, namely, Quantum Molecular Dynamics (QMD) [22][23][24] and Boltzmann-Nordheim-Vlasov (BNV) [15,17]. Model analysis showed [25][26][27][28] that the direct component follows the systematic of the Gold haber formalism with a width parameter that is in a reasonable agreement, while the transport description (BNV) of the direct component is not reproduced by the calculations and describes mainly the dissipative component of the experimental spectra. A possible reason is, that BNV includes mean field dynamics and direct nucleon-nucleon (NN) interactions enters only through a collision term.…”