Vector resonances from a strong electroweak sector at linear colliders

We explore the usefulness of very energetic lineare ⁺ e ^? colliders in the TeV range in studying an alternative scheme of electroweak symmetry breaking based on a strong interacting sector. The calculations are performed within the BESS model which contains new vector resonances. If the massM _V of the new boson multiplet lies not far from the maximum machine energy, or if it is lower, such a resonant contribution would be quite manifest. A result of our analysis is that also virtual effects are important. It appears that annihilation into a fermion pair in such machines, at the considered luminosities, would improve only marginally on existing limits if polarized beams are available and left-right asymmetries are measured. On the other hand, the process ofW-pair production bye ⁺ e ^? annihilation would allow for sensitive tests of the hypothesized strong sector, especially if theW polarizations are reconstructed from their decay distributions, and the more so the higher the energy of the machine. Ane ⁺ e ^? collider with c.m. energy \(\sqrt s = 500\) GeV could improve the limits on the model for the range 500<M _V (GeV)<1000 whenW polarization is not reconstructed. IfW polarizations are reconstructed, then the bounds improve for the entire expected range ofM _V . These bounds become more stringent for larger energy of the collider. We have also studied the detectability of the new resonances through the fusion subprocesses, but this channel does not seem to be interesting even for a collider with a c.m. energy \(\sqrt s = 2\) TeV.     

Soil compaction and over-winter changes to tracked-vehicle ruts, Yakima Training Center, Washington

We monitored two experimental areas at the Yakima Training Center (YTC) in central Washington to measure changes to M1A2 Abrams (M1) tank-rut surface geometry and in- and out-of-rut saturated hydraulic conductivity (K_fs), soil penetration resistance (SPR) and soil bulk density (BD). Profile-meter data show that rut cross-sectional profiles smoothed significantly and that turning ruts did so more than straight ruts. Rut edges were zones of erosion and sidewall bases were zones of deposition. K_fs values were similar in and out of ruts formed on soil with 0–5% moisture by volume, but were lower in ruts formed on soil with about 15% water. Mean SPR was similar in and out of ruts from 0- to 5-cm depth, increased to 2 MPa outside ruts and 4 MPa inside ruts at 10- to 15-cm depth, and decreased by 10–38% outside ruts and by 39–48% inside ruts at the 30-cm depth. Soil BD was similar in and out of ruts from 0- to 2.5-cm depth, and below 2.5 cm, it was generally higher in ruts formed on moist soil with highest values between 10- and 20-cm depth. Conversely, BD in ruts formed on dry soil was similar to out-of-rut BD at all depths. This information is important for determining impacts of tank ruts on water infiltration and soil erosion and for modifying the Revised Universal Soil Loss Equation (RUSLE) and the Water Erosion Prediction Project (WEPP) models to more accurately predict soil losses on army training lands.     

Preparation of photoluminescent PMMA doped with tris(pyrazol-1-yl)borate lanthanide complexes

The neutral homoleptic Ln(III) complex Ln(Tp)₃ (Ln=Sm, Eu, Tb, Yb; Tp=hydrotris(pyrazol-1-yl)borate) were used as dopants for the preparation of novel photoluminescent poly(methyl methacrylate) glasses indicated as Ln(Tp)₃@PMMA. The doped polymers containing samarium, europium and terbium derivatives showed emission associated to f–f transitions in the visible range upon excitation with UV light, while a NIR emission was obtained from Yb(Tp)₃@PMMA. The maximum incident wavelength able to induce emissions from the Ln(Tp)₃-doped polymers depends upon the choice of the lanthanide ion. No meaningful antenna-effect was instead observed using dysprosium as metal centre.     

Non-destructive characterization of fifty various species of pigments of archaeological and artistic interest by using the portable X-ray diffraction system of the LANDIS laboratory of Catania (Italy)

In recent years a portable XRD system with high angular resolution and rapid measurement time was realized at the LANDIS laboratory of the LNS-INFN and IBAM-CNR of Catania (Italy) for application in the cultural heritage field. The system was previously used for the characterization of some pigments present in ancient frescoes. The main task of this work is to show the possibility of using the above portable diffractometer in the identification of a large variety of pigments commonly used to realize archaeological and artistic masterpieces.50 reference standards of pigments with a known mineralogical composition were prepared and measured; analytical results evidenced both the advantages and the limitations of using such a system in the analysis of different typologies of pigments and allowed to realize a raw database to be used during the characterization of real samples.