Code Usage Analysis System (CUAS)

A set of computer programs is offered to aid a user in evaluating performance of an application program. The system provides reports of subroutine usage, program errors, and segment loading which occurred during the execution of an application program. It is presented in support of the development and validation of the space vehicle dynamics project

Low-lying fermion modes of Nf=2 improved Wilson fermions

We present preliminary results for the topological charge and susceptibility determined from the low-lying eigenmodes of the Wilson-Dirac operator. These modes have been computed on dynamical configurations with Nf=2 non-perturbatively improved Wilson fermions. We compare our results with the eigenmodes of fermions in the quenched approximation.Comment: Lattice2001(confinement), 3 pages, 5 Figure

Application of General Purpose Computer Techniques to the Design of a Programmable PCM Telemetry Decommutator

This paper describes design of a programmable decomrnutator for multi-format PCM telemetry data. The decommutator organization includes a program counter, instruction decoding registers, and an arithmetic unit, together with pattern comparison logic, and synchronization decision networks. The various types of input formats are discussed and their implications on the organization are determined. The input data formats include (a) normal PCM commutation with frame synchronization and subcommutation synchronization, (b) mixes of different rate PCM commutation, (c) word synchronization and (d) data address tags with each data word. The decommutator is organized around a coincident current memory which serves for both program storage and data buffering. A system of program interrupts is also provided so that (a) data words can be requested from the buffer by an asynchronous device, and (b) new programs can be loaded into unused sections of memory. The second feature permits immediate changes of input format by initiating only one manual command. The address and control fields of the program instructions are defined to allow all of the synchronization parameters (i.e. error tolerance) to be contained as part of the program

A lattice determination of moments of unpolarised nucleon structure functions using improved Wilson fermions

Within the framework of quenched lattice QCD and using O(a) improved Wilson fermions and non-perturbative renormalisation, a high statistics computation of low moments of the unpolarised nucleon structure functions is given. Particular attention is paid to the chiral and continuum extrapolations.Comment: LaTeX, 66 pages, 22 figure

The electric dipole moment of the nucleon from simulations at imaginary vacuum angle theta

We compute the electric dipole moment of proton and neutron from lattice QCD simulations with N_f=2 flavors of dynamical quarks at imaginary vacuum angle theta. The calculation proceeds via the CP odd form factor F_3. A novel feature of our calculation is that we use partially twisted boundary conditions to extract F_3 at zero momentum transfer. As a byproduct, we test the QCD vacuum at nonvanishing theta.Comment: 22 pages, 10 figure

Vacuum polarisation and the muon g-2 in lattice QCD

We measure the hadronic contribution to the vacuum polarisation tensor, and use it to estimate the hadronic contribution to (g-2)_mu, the muon anomalous magnetic moment.Comment: 3 pages, 4 figures, Latex. Talk given by P.E.L. Rakow at Lattice2003(matrix