Solid-deuterium-initiated Z-pinch experiments are numerically simulated using a two-dimensional resistive magnetohydrodynamic model, which includes many important experimental details, such as ``cold-start`` initial conditions, thermal conduction, radiative energy loss, actual discharge current vs. time, and grids of sufficient size and resolution to allow realistic development of the plasma. The alternating-direction-implicit numerical technique used meets the substantial demands presented by such a computational task. Simulations of fiber-initiated experiments show that when the fiber becomes fully ionized rapidly developing m=0 instabilities, which originated in the coronal plasma generated from the ablating fiber, drive intense non-uniform heating and rapid expansion of the plasma column. The possibility that inclusion of additional physical effects would improve stability is explored. Finite-Larmor-radius-ordered Hall and diamagnetic pressure terms in the magnetic field evolution equation, corresponding energy equation terms, and separate ion and electron energy equations are included; these do not change the basic results. Model diagnostics, such as shadowgrams and interferograms, generated from simulation results, are in good agreement with experiment. Two alternative experimental approaches are explored: high-current magnetic implosion of hollow cylindrical deuterium shells, and ``plasma-on-wire`` (POW) implosion of low-density plasma onto a central deuterium fiber. By minimizing instability problems, these techniques may allow attainment of higher temperatures …

The Los Alamos High Density Z Pinch-II (HDZP-II) facility is used to study the dynamics of z-pinch plasmas generated from solid fibers of deuterated polyethylene CD{sub 2} with a range in radii of 3--60 {mu}m. HDZP-II is a pulsed-power generator that delivers a current that rises to 700 kA in 100 ns through an inductive load. A multiframe circular schlieren records the evolution of the shape and size of the plasma on seven images taken at 10-ns intervals. These circular-schlieren images show very strong m=0 instability at the onset of current and a rapid radial expansion of the plasma. No higher-order instabilities are observed. An interferometer is used to infer the electron density and electron line density, giving a measure of the fraction of plasma contained within the outline of the circular-schlieren image at one time during the multiframe sequence. A three-channel x-ray crystal-reflection spectrometer provides the time-resolved, spatially-averaged electron temperature. The magnitude of the x-ray emission at these energies also gives qualitative information about the electron temperature and density at late times. A lower bound on the ion temperature is inferred from the particle pressure needed to balance the magnetic field pressure. The ion temperature rose above that of …

The Z + {gamma} cross-section x branching ratio in the electron channel has been measured using the inclusive Z data sample from the CDF 1988--1989 collider run, for which the total integrated luminosity was 4.05 {plus_minus} 0.28 pb{sup {minus}1}. Two Z{gamma} candidates are observed from central photon events with {Delta}R/{sub {gamma}} > 0.7 and E{sub t}{sup {gamma}} > 5.0 GeV. From these events the {sigma} * BR(Z + {gamma}) is measured and compared with SM predictions: {sigma} * BR(Z + {gamma}){sub e} = 6.8{sub {minus}5.7}{sup +5.7}(stat + syst)pb {sigma} * BR(Z + {gamma})SM = 4.7{sub {minus}4.7}{sup +0.7}(stat + syst)pb. From this ZZ{sub {gamma}} cross section measurement limits on the Z{sub {gamma}{gamma}} and couplings for three different choices of compositeness scale {Lambda}{sub Z} are obtained. The experimental sensitivity to the h{sub 30}{sup Z,{gamma}}/h{sub 10}{sup Z,{gamma}} couplings is in the range of {Lambda}{sub Z} {approximately} 450--500 GeV and for the h{sub 40}{sup Z{gamma}}/h{sub 20}{sup Z,{gamma}} couplings {Lambda}{sub Z} {approximately} 300 GeV.

This dissertation work includes a series of experimental measurements in a search for better understanding of high temperature (10{sup 4}-10{sup 6}K) and high density plasmas (10{sup 22}-10{sup 24}cm{sup {minus}3}) produced by irradiating a transparent solid target with high intensity (10{sup 13} - 10{sup 15}W/cm{sup 2}) and subpicosecond (10{sup {minus}12}-10{sup {minus}13}s) laser pulses. Experimentally, pump and probe schemes with both frontside (vacuum-plasma side) and backside (plasma-bulk material side) probes are used to excite and interrogate or probe the plasma evolution, thereby providing useful insights into the plasma formation mechanisms. A series of different experiments has been carried out so as to characterize plasma parameters and the importance of various nonlinear processes. Experimental evidence shows that electron thermal conduction is supersonic in a time scale of the first picosecond after laser irradiation, so fast that it was often left unresolved in the past. The experimental results from frontside probing demonstrate that upon irradiation with a strong (pump) laser pulse, a thin high temperature ({approximately}40eV) super-critical density ({approximately}10{sup 23}/cm{sup 3}) plasma layer is quickly formed at the target surface which in turn becomes strongly reflective and prevents further transmission of the remainder of the laser pulse. In the bulk region behind the surface, …

This thesis presents a measurement of the partial decay width of the Z{sup 0} to e{sup +}e{sup {minus}} using data recorded by the SLD at the SLAC Linear Collider during the 1992 run. Based on 354 nb{sup {minus}1} of data, the decay width, {Gamma}{sub ee} is measured to be 82.4 {+-} 3.6/3.7 {+-} 0.8 MeV where the first error is statistical and the second is systematic. By combining this measurement of {Gamma}{sub ee} with the SLD measurement of A{sub LR}, the magnitude of the effective vector and axial-vector coupling constants of the electron, {anti g}{sub v}{sup e} and {anti g}{sub a}{sup e}, are determined to be 0.024 {+-} 0.011 and 0.498 {+-} 0.011 respectively.