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Nucleon knockout experiments using beryllium or carbon targets reveal a strong dependence of the quenching factors, i.e., the ratio ( R s ) of theoretical to the experimental spectroscopic factors ( C 2 S ), on the proton-neutron asymmetry in the nucleus under study. However, this dependence is greatly reduced when a hydrogen target is used. To understand this phenomenon, exclusive 1 H (17 Ne , 2 p 16 F) and inclusive 12 C (17 Ne , 2 p 16 F) X , 12 C (17 Ne , 16 F) X as well as 1 H (17 Ne , 16 F) X (X-denotes undetected reaction products) reactions with 16 F in the ground and excited states were analysed. The longitudinal momentum distribution of 16 F and the correlations between the detached protons were studied. In the case of the carbon target, there is a significant deviation from the predictions of the eikonal model. The eikonal approximation was used to extract spectroscopic factor values C 2 S . The experimental C 2 S value obtained with C target is markedly lower than that for H target. This is interpreted as rescattering due to simultaneous nucleon knockout from both reaction partners, 17 Ne and 12 C . [ABSTRACT FROM AUTHOR]

Neutron-rich lead and bismuth isotopes have been produced by cold-fragmentation reactions induced by 238U projectiles at 1A GeV impinging on a beryllium target. The high-resolving power FRagment Separator (FRS) at GSI allowed us to identify and determine the production cross-sections of 43 nuclei, nine of them for the first time ( 216, 217, 218, 219Pb and 219, 220, 221, 222, 223Bi . These data are compared to other previously measured cross-sections in similar reactions and model calculations. [ABSTRACT FROM AUTHOR]

Breakup reactions were used to study the ground-state configuration of the neutron-rich isotope 23O. The 22O fragments produced in one-nucleon removal from 23O at 938 MeV/nucleon in a carbon target were detected in coincidence with de-exciting γ rays, allowing to discern between 22O ground-state and excited-states contributions. From the comparison of exclusive experimental momentum distributions for the one-neutron removal channel to theoretical momentum distributions calculated in an Eikonal model for the knockout process, and spin and parity assignment of Iπ = 1/2+ was deduced for the 23O ground state. This result solved the existent experimental discrepancy. [ABSTRACT FROM AUTHOR]

The projectile fragmentation of a 92 Mo beam onto a beryllium target at an incident energy of 500 A MeV has been studied at the high-resolution spectrometer FRS at GSI. The isotopic production cross-sections of the projectile fragments produced in the reaction have been determined. The data have been compared to the empirical parameterisation, EPAX, and to a microscopic nuclear reaction model, ABRABLA. [ABSTRACT FROM AUTHOR]

Relativistic projectile fragmentation of208Pb has been used to produce isomers in neutron-rich,A˜ 190 nuclides. A forward-focusing spectrometer provided ion-by-ion mass and charge identification. The detection of ?-rays emitted by stopped ions has led to the assignment of isomers in188Ta,190W,192Re,193Re,195Os,197Ir,198Ir,200Pt,201Pt,202Pt and203Au, with half-lives ranging from approximately 10 ns to 1 ms. Tentative isomer information has been found also for174Er,175Er,185Hf,191Re,194Re and199Ir. In most cases, time-correlated, singles ?-ray events provided the first spectroscopic data on excited states for each nuclide. In200Pt and201Pt, the assignments are supported by ?-? coincidences. Isomeric ratios provide additional information, such as half-life and transition energy constraints in particular cases. The level structures of the platinum isotopes are discussed, and comparisons are made with isomer systematics. [ABSTRACT FROM AUTHOR]

One-neutron removal cross-sections ( ) of 17, 19C in various targets at about 900 MeV/nucleon, and one-proton removal cross-sections ( ) of 8, 10B at about 1400 MeV/nucleon were measured using the fragment separator FRS at GSI. A significant increase of for 19C compared to its neighbors was observed. The same behavior was found for for the neutron-deficient nucleus 8B compared to the stable isotope 10B. These results support a one-neutron halo structure in 19C and a one-proton halo in 8B. [ABSTRACT FROM AUTHOR]

Absolute differential cross-sections for elastic p6He and p8He scattering were measured in inverse kinematics with secondary beams. In order to supplement data taken for small-angle scattering, differential cross-sections for higher momentum transfer were measured using liquid hydrogen target. Both data sets were analyzed together. They have permitted to deduce the radial shape of the nuclear matter distributions and the root-mean-square radii with the help of Glauber theory. In addition to a phenomenological analysis, used already in the previous work, a model-independent analysis with a help of a Sum-Of-Gaussians (SOG) method has been performed. The experimental p6,8He elastic scattering cross-sections have also been compared with the predictions from various theoretical nuclear models. [ABSTRACT FROM AUTHOR]