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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]

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]

Elastic and inelastic scattering as well as transfer transitions involving a valence proton in the sd- and fp- shell orbits are studied in the interaction ofCl +S at E=50 MeV. Experimental angular distributions of single particle states ofCl (elastic and inelastic transfer) are presented with a CRC analysis. In the CRC calculations the effects of inelastic and transfer couplings are studied using known spectroscopic information. In the CRC analysis six single particle bound states and the collective 2 excitation ofS are included in the coupling scheme. Higher order coupling effects are found to be important. A distinct effect, the mixing of single particle states (of different parity) due to direct and transfer interactions is observed to produce an enhancement of the transfer cross section to the low lying states. This feature is due to a change of the asymptotically defined single nucleon orbits via polarization in the field of the other nucleus, an effect which is analogous to hybridization, known from atomic physics. [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]