Is the chiral phase transition in non-compact lattice QED driven by monopole condensation?

We investigate the recent conjecture that the chiral phase transition in non-compact lattice QED is driven by monopole condensation. The comparison of analytic and numerical results shows that we have a quantitative understanding of monopoles in both the quenched and dynamical cases. We can rule out monopole condensation. (orig.)Available from TIB Hannover: RA 2999(93-025) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

The present status of non-compact lattice QED

We give a 1993 update of non-compact lattice QED, in particular the chiral condensate, finite size effects and meson mass ratios. We compare descriptions of the phase transition. Our previous conclusions remain valid. (orig.)SIGLEAvailable from TIB Hannover: RA 2999(93-178) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

Spectroscopy and renormalisation group flow of a lattice Nambu-Jona-Lasinio model

We investigate a lattice Nambu-Jona-Lasinio model both by the Monte Carlo method and Schwinger-Dyson equations. A comparison allows the discussion of finite size effects and the extrapolation to infinite volume. We pay special attention to the identification of particles and resonances. This enables us to discuss renormalisation group flows in the neighbourhood of the critical coupling where the chiral symmetry breaking phase transition takes place. In no region of the bare parameter space do we find renormalisability for the model. (orig.)SIGLEAvailable from TIB Hannover: RA 2999(93-195) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

Seeking the equation of state of non-compact lattice QED

We perform a high statistics calculation of the equation of state for non-compact QED on large lattices. The calculation extends to fermionic correlation lengths of #approx#8, and it is combined with a finite size scaling analysis of the lattice data. (orig.)23 refs.Available from TIB Hannover: RA 2999(96-084) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

The Drell-Yan process and deep inelastic scattering from the lattice

We report on measurements of the h_1 structure function, relevant to calculating cross-sections for the Drell-Yan process. This is a quantity can not be measured in deep inelastic scattering, it gives additional information on the spin carried by the valence quarks, as well as insights on how relativistic the quarks are. (orig.)8 refs.Available from TIB Hannover: RA 2999(96-152) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

A preliminary lattice study of the glue in the nucleon

About half the mass of a hadron is given from gluonic contributions. In this talk we calculate the chromo-electric and chromo-magnetic components of the nucleon mass. These computations are numerically difficult due to gluon field ultra-violet fluctuations. Nevertheless a high statistics feasibility run using quenched Wilson fermions seems to show reasonable signals. (orig.)SIGLEAvailable from TIB Hannover: RA 2999(96-127) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman