This report contains a general introduction, the experimental section, general conclusions, and two appendices: using projection operators to construct the basis functions and the magnetic transition of bulk pyrrhotite samples in the low-temperature range. Four chapters have been removed for separate processing. They are: From pyrrhotite to troilite: An application of the Landau theory of phase transitions; Phase transition in near stoichiometric iron sulfide; A ordering, incommensuration and phase transitions in pyrrhotite. Part 1: A TEM study of Fe{sub 7}S{sub 8}; and Part 2: A high-temperature X-ray powder diffraction and thermomagnetic study.

A search for charmless dihadron decays of neutral b-hadrons was performed using data obtained from 800 GeV/c proton-gold interactions. The following upper limits on the b-hadron branching ratios (including charge conjugates) were obtained at the 90% confidence limit: Br(B{sub s} {yields} K{sup +}K{sup {minus}}) + r{sub s} x Br(B{sub d} {yields} {pi}{sup +}{pi}{sup {minus}}) < 2.0 x 10{sup {minus}3}; Br(B{sub d} {yields} K{sup +}K{sup {minus}}) < 9.5 x 10{sup {minus}4}; Br(B{sub s} {yields}{pi}{sup +}{pi}{sup {minus}}) < 2.0 x 10{sup {minus}3}; Br(B{sub d} {yields} K{sup +}{pi}{sup {minus}}) < 1.9 x 10{sup {minus}3}; Br(B{sub s} {yields} K{sup {minus}}{pi}{sup +}) < 2.2 x 10{sup {minus}3}; Br(B{sub d} {yields} p{bar p}) < 1.6 x 10{sup {minus}3}; Br(B{sub s} {yields} p{bar p}) < 9.0 x 10{sup {minus}3}; Br({Lambda}{sub d} {yields} K{sup +}p{sup {minus}}) < 6.1 x 10{sup {minus}3}; Br({Lambda}{sub b} {yields} {pi}{sup +}p{sup {minus}}) < 9.7 x 10{sup {minus}3}; where r{sub s} was determined to be 2.9 {+-} 0.8. These limits assume that B{sub d}/B{sub s}/{Lambda}{sub b} hadrons are produced in proton on nucleon interactions in the ratio (38 {+-} 5.7) : (13 {+-} 3.2) : (9.6 {+-} 1.7) and that the branching ratio for the cascade decay b-hadron {yields} J/{psi} + X {yields} {mu}{sup …

A resolution function has been determined for scattered neutron experiments at Rensselaer Polytechnic Institute (RPI). This function accounts for the shifting and broadening of the resonance peak due to the additional path length, traveled by the neutron after scattering and prior to detection, along with the broadening of the resonance peak due to the bounce target. This resolution function has been parameterized both in neutron energy and size of the sample disk. Monte Carlo Neutron and Photon (MCNP) modeling has been used to determine the shape of the detector resolution function while assuming that the sample nucleus has an infinite mass. The shape of the function for a monoenergetic neutron point source has been compared to the analytical solution. Additionally, the parameterized detector resolution function has been used to broaden the scatter yield calculated from Evaluated Neutron Data File ENDF/B-VI cross section data for {sup 238}U. The target resolution function has been empirically determined by comparison of the broadened scatter yield and the experimental yield for {sup 238}U. The combined resolution function can be inserted into the SAMMY code to allow resonance analysis for scattering measurements.