We have observed bottom-charm mesons via the decay mode B-c(+/-) --> J/psi l(+/-)v in 1.8 TeV p (p) over bar collisions using the CDF detector at the Fermilab Tevatron. A fit of background and signal contributions to the J/psi l mass distribution yielded 20.4(-5.5)(+6.2) events from B-c mesons. A fit to the same distribution with background alone was rejected at the level of 4.8 standard deviations. We measured the B-c(+) mass to be 6.40 +/- 0.39(stat) +/- 0.13(syst) GeV/c(2) and the B-c(+) lifetime to be 0.46(-0.16)(+0.18)(stat) +/- 0.03(syst) ps. Our measured yield (production cross section times branching ratio) for B-c(+) --> J/psi l(+)v relative to that for B+ --> J/psi K+ is 0.132(-0.037)(+0.041)(stat) +/- 0.031 (syst)(-0.020)(+0.032)(lifetime)

Monte Carlo simulations for particle and -ray emissions from a compound nucleus based on the Hauser-Feshbach statistical theory with pre-equilibrium emission are performed. The simulation yields reliable nuclear-reaction-wise energy spectra, or so-called exclusive spectra, for emitted neutrons and -rays, which are required in particle transport calculations for nuclear applications. The Monte Carlo method is applied to neutron-induced nuclear reactions on 56 Fe, and the results are compared with a traditional deterministic method. The neutron and -ray emission correlation is examined by gating on an 847 keV -ray that is produced by an inelastic scattering process. The partial -ray energy spectra for different -ray multiplicities are inferred using this Monte Carlo method. In addition, we investigate a correlation between two neutrons in the (n,2n) reaction.

Monte Carlo simulations for particle and -ray emissions from a compound nucleus based on the Hauser-Feshbach statistical theory with pre-equilibrium emission are performed. The simulation yields reliable nuclear-reaction-wise energy spectra, or so-called exclusive spectra, for emitted neutrons and -rays, which are required in particle transport calculations for nuclear applications. The Monte Carlo method is applied to neutron-induced nuclear reactions on 56 Fe, and the results are compared with a traditional deterministic method. The neutron and -ray emission correlation is examined by gating on an 847 keV -ray that is produced by an inelastic scattering process. The partial -ray energy spectra for different -ray multiplicities are inferred using this Monte Carlo method. In addition, we investigate a correlation between two neutrons in the (n,2n) reaction.

The nucleon direct-semidirect (DSD) capture cross sections are obtained by calculating a transition amplitude to the Hartree-Fock-BCS bound states. The radial matrix elements in the DSD amplitudes are calculated from the radial part of the single-particle wave functions. For deformed nuclei the single-particle states are expanded in the cylindrical harmonic-oscillator basis and then projected on the spherical harmonic-oscillator basis. The pairing correlations are treated in the BCS approach and the calculated spectroscopic factors are in fairly good agreement with experimental data in the even tin isotopes from 116 Sn to 124 Sn. The resulting DSD cross sections for the neutron capture by 208 Pb and 238 U are found to be in good agreement with the available experimental data. The calculations are also performed for the neutron capture on 122 Sn and 132 Sn isotopes that are important for the r-process in astrophysics.