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Abstract: The ion dose deposition in tissues is characterized by a favorable depth dose profile (i.e. Bragg peak) and a small lateral spread. In order to keep these benefits of ions in cancer treatments, a very high accuracy is required on the dose deposition (±3%). For given target stoichiometry and geometry, the largest uncertainty on the physical dose deposition is due to the ion nuclear fragmentation. We have performed an experiment at GANIL with a 95MeV/u 12C beam on thick tissue equivalent PMMA targets (thicknesses: 5, 10, 15, 20 and 25mm). The main goals of this experiment are to provide experimental fragmentation data for benchmarking the physical models used for treatment planning. Production rates, energy and angular distributions of charged fragments have been measured. The purpose of this paper is to present the results of this experiment. [Copyright &y& Elsevier]

Independent fission fragment yields have been obtained for the six fragment pairs ( Z L/ Z H = 44/46 , 42/48, 40/50, 38/52, 36/54 and 34/56) in 208Pb(18O, f ) at the beam energy E = 85 MeV. γ -ray spectroscopy technique was applied to analyze the experimental data. With use of these data the mass distribution of fission fragments was restored. Data on average fragment spin distribution and total neutron multiplicity are presented. The agreement of the obtained results with other experimental data proves the validity of the applied method to solve this kind of problems. [ABSTRACT FROM AUTHOR]

The measurement of the two-particle correlation function for different particle species allows to obtain information about the development of the particle emission process: the space-time properties of emitting sources and the emission time sequence of different particles. The single-particle characteristics and two-particle correlation functions for neutral and charged particles registered in forward direction are used to determine that the heavy fragments (deuterons and tritons) are emitted in the first stage of the reaction (pre-equilibrium source) while the majority of neutrons and protons originates from the long-lived quasi-projectile. The emission time sequence of protons, neutrons and deuterons has been obtained from the analysis of non-identical particle correlation functions. [ABSTRACT FROM AUTHOR]

Abstract: We analyzed the experimental data of the pre-scission neutron multiplicity in connection with fission fragments in the reaction 58Ni+ 208Pb at the incident energy corresponding to the excitation energy of the compound nucleus , which was performed by DéMoN group. The relation between the pre-scission neutron multiplicity and each reaction process having different reaction time is investigated. In order to study the fusion–fission process accompanied by neutron emission, the fluctuation–dissipation model combined with a statistical model is employed. It is found that the fusion–fission process and the quasi-fission process are clearly distinguished in correlation with the pre-scission neutron multiplicity. [Copyright &y& Elsevier]

The 4H resonance was investigated in the transfer reactions 2H(t, p)4H and 3H(t, d)4H using cryogenic liquid targets of deuterium and tritium and 58 MeV triton beam. The multidetector system with a large angular acceptance was used to measure the recoil protons and deuterons in coincidences with tritons or neutrons from the decay of 4H. Data analysis involved careful considerations made for the competing processes of final state interaction and quasifree scattering. The experimental data show a peak with resonance parameters Eres=3.05±0.19 MeV and Γobs=4.18±1.02 MeV. The pole of S-matrix corresponding to the physical values of energy and width, E0=1.99±0.37 MeV and Γ0=2.85±0.3 MeV, has been extracted. [Copyright &y& Elsevier]

Multi-parameter correlation study of the reaction 242Pu(p, f) at Ep = 13, 20 and 55 MeV has been carried out. Fission fragment mass and kinetic energy distributions and the double differential neutron spectra have been measured. It was observed that the two-humped shape of mass distributions prevailed up to highest proton energy. Manifestation of the nuclear shell Z = 28 near fragment mass Afr = 70 has been detected. The experimental results were analyzed in the framework of a time-dependent statistical model with inclusion of nuclear friction effects in the fission process. The multi-parameter correlation study of the reaction. [Copyright &y& Elsevier]

The fusion-fission process for the synthesis of superheavy elements is discussed on the basis of the fluctuation-dissipation model. We employ three-dimensional langevin equation. We investigate the fusion-fission process by analyzing not only the mass distribution of fission fragments but also the neutron multiplicity in fusion-fission process. [Copyright &y& Elsevier]

To investigate [sup 5]H resonance states with a better instrumental resolution, we utilized the two-neutron transfer reaction [sup 3]H(t,p)[sup 5]H accomplished with the use of a cryogenic liquid-tritium target and 57.5-MeV triton beam. As a result of this study, a valuable fraction of protons detected at θ[sub lab]=18[sup °]–32[sup °] in ptn coincidence events was attributed to the states of the [sup 5]H nucleus. Two resonance states situated at 1.8±0.1 and 2.7±0.1 MeV above the t+n+n decay threshold were obtained in the missing mass energy spectrum of the [sup 5]H nucleus. The peak located close to E[sub [sup 5]H]=1.8 MeV was clearly seen in the [sup 5]H spectrum obtained from the energy distributions of [sup 3]H nuclei emitted in the reaction [sup 2]H([sup 6]He, [sup 5]H)[sup 3]He at θ[sub lab]=17[sup °]–32[sup °]. The width (Γ[sub obs]≤0.5 MeV) obtained for the two [sup 5]H resonance states is surprisingly small. A state of [sup 4]H with E[sub res]=3.3 MeV and γ[sup 2]=2.3 MeV was obtained in the reaction [sup 2]H(t, p)[sup 4]H from the spectra of protons leaving the target at θ[sub lab]=18[sup °]–32[sup °] and detected in coincidence with neutrons emitted in the decay of [sup 4]H nuclei.© 2003 MAIK “Nauka / Interperiodica”. [ABSTRACT FROM AUTHOR]

Data have been obtained on exclusive single neutron knockout cross sections from 12Be to study its ground state structure. Preliminary cross sections for the first (0.32 MeV, $\ensuremath{^1\!/_2 ^-}$) and second (1.78 MeV, $\ensuremath{^5\!/_2 ^+}$, unbound) excited states in 11Be have been obtained, giving evidence of significant admixtures of both $\ensuremath{\nu(1p_{^1\!/_2})^2}$ and $\ensuremath{\nu(1d_{^5\!/_2})^2}$ configurations in the ground state of 12Be. [ABSTRACT FROM AUTHOR]