Characterization of a Pre-Trajan wall by integrated geophysical methods

The purpose of this study was to characterize a pre-Trajan mosaic-decorated wall structure located beneath the Cryptoporticus of the 'Baths of Trajan' complex in Rome. The surveyed wall is 15m long, 0.9m wide and 3 to 5m high. Ground penetrating radar (GPR) and P-wave seismic refraction tomography profiles were used to reconstruct the wall's inner structure, generate a map of the fractures and to evaluate the seismic velocities of the building materials. The wall was surveyed with horizontally and vertically dense GPR profiles and two seismic lines. The seismic lines and GPR profiles were capable of detecting a discontinuity between brick and travertine materials that compose the wall. The combined interpretation of the two non-invasive techniques allowed us to locate weak zones and fractures. This rapid, non-destructive and multi-parametric approach has proved to be effective for characterizing the current status of the wall and the results will be used by archaeologists to evaluate the wall's integrity and to preserve the structure in the future archaeological excavations

Light-front CQM calculations of baryon electromagnetic form factors

The parameter-free predictions for the $N - P_{11}(1440)$ and $N - P_{33}(1232)$ electromagnetic transition form factors, obtained within our light-front constituent quark model using eigenfunctions of a baryon mass operator which includes a large amount of configuration mixing, are reported. The effects due to small components in the baryon wave functions, such as S'- and D-wave, are also investigated.Comment: to appear in the Proceedings of the International Workshop on Hadron Dynamics with the new DAPHNE and CEBAF facilities, Frascati, Italy, 11-14 November 199

Creating a Religious Properties Database for the City of New Bedford: an Analysis of Best Practices and Available Systems

This policy analysis was written to provide the city of New Bedford, the Waterfront Historic Area League, Inter-church Council of Greater New Bedford, and the congregations with possible database systems to consider in creating their historic religious properties database. It also provides the best methodology to use when choosing a database. Deciding on who will be involved in the choosing process, determining a budget, and listing the mandatory requirements the database should provide are all important to consider in the decision making process

Relativistic effects on the neutron charge form factor in the constituent quark model

The neutron charge form factor GEn(Q**2) is investigated within a constituent quark model formulated on the light-front. It is shown that, if the quark initial motion is neglected in the Melosh rotations, the Dirac neutron form factor F1n(Q**2)$receives a relativistic correction which cancels exactly against the Foldy term in GEn(Q**2), as it has been recently argued by Isgur. Moreover, at the same level of approximation the ratio of the proton to neutron magnetic form factors GMp(Q**2) / GMn(Q**2) is still given by the naive SU(6)-symmetry expectation, -3/2. However, it is also shown that the full Melosh rotations break SU(6) symmetry, giving rise to GEn(Q**2) =/ 0 and GMp(Q**2)/GMn(Q**2) =/ -3/2 even when a SU(6)-symmetric canonical wave function is assumed. It turns out that relativistic effects alone cannot explain simultaneously the experimental data on GEn(Q**2)$ and GMp(Q**2)/GMn(Q**2).Comment: final version with one minor correction and updated references; to appear in Physics Letters

2D approach for modelling self-potential anomalies. Application to synthetic and real data

The aim of this work is to present a 2-D Matlab code based on the finite element method for providing numerical modelling of both groundwater flow and self-potential signals. The distribution of the self-potential is obtained by starting with the solution of the groundwater flow, then computing the source current density, and finally calculating the electrical potential. The reliability of the algorithm is tested with synthetic case studies in order to simulate both the electric field resulting from the existence of a leak in the dam and SP signals associated with a pumping test in an unconfined aquifer. In addition, the algorithm was applied to field data for the localization of piping sinkholes. The results show that the outputs of the algorithm yielded satisfactory solutions, which are in good agreement with those of previous studies and field investigations. In details, the synthetic data and SP anomalies calculated by using the code are very close in terms of sign and magnitude, while real data tests clearly indicated that the computed SP signals were found to be consistent with the measured values

Isgur-Wise form factors of heavy baryons within a light-front constituent quark model

The space-like elastic form factors of baryons containing a heavy quark are investigated within a light-front constituent quark model in the limit of infinite heavy-quark mass, adopting a gaussian-like ansatz for the three-quark wave function. The results obtained for the Isgur-Wise form factors corresponding both to a spin-0 and a spin-1 light spectator pair are presented. It is found that the Isgur-Wise functions depend strongly on the baryon structure, being sharply different in case of diquark-like or collinear-type configurations in the three-quark system. It is also shown that the relativistic effects lead to a saturation property of the form factors as a function of the baryon size. Our results are compared with those of different models as well as with recent predictions from QCD sum rules and lattice QCD simulations; the latter ones seem to suggest the dominance of collinear-type configurations, in which the heavy-quark is sitting close to the center-of-mass of the light quark pair.Comment: latex, 15 pp., 6 figures with epsfig.st

A light-front description of electromagnetic form factors for J≤3/2J \leq {3/2} hadrons

A review of the hadron electromagnetic form factors obtained in a light-front constituent quark model, based on the eigenfunctions of a mass operator, is presented. The relevance of different components in the q-q interaction for the description of hadron experimental form factors is analysed.Comment: 6 pages, Latex, 3 Postscript figures included. Proceedings of "Nucleon 99", Frascati, June 1999. To appear in Nucl. Phys.