Neutrino Physics

The author reports inclusive and exclusive searches for neutral currents, the scaling of charged current interactions, and searches for heavy leptons and charmed particles. (23 refs)

Hadron Spectroscopy with Dynamical Chirally Improved Fermions

We simulate two dynamical, mass degenerate light quarks on 16^3x32 lattices with a spatial extent of 2.4 fm using the Chirally Improved Dirac operator. The simulation method, the implementation of the action and signals of equilibration are discussed in detail. Based on the eigenvalues of the Dirac operator we discuss some qualitative features of our approach. Results for ground state masses of pseudoscalar and vector mesons as well as for the nucleon and delta baryons are presented.Comment: 26 pages, 17 figures, 10 table

Chimney Foundation on Drilled Piers

This paper describes the design and compares predicted performance to actual responses of a drilled pier foundation supporting a 305m high chimney. The purpose was to evaluate laboratory and empirical side friction and end bearing criteria used in the pier design. Based on results of a subsurface exploration program, and consideration of vibration effects on nearby structures, a foundation system was designed consisting of 38 drilled piers capped with a concrete mat. The piers had an average diameter of 1.37m in soil and 1.22m in rock. The average length of pier was 15.63m including a rock socket 2.44m deep. Each pier was designed to support a maximum compressional load of 1,362 tons. The side friction and end bearing capacity was analyzed from data accumulated under construction and service conditions. A comparison of this analysis with criteria suggested by others indicated compliance with accepted design standards

Nucleon decay and atmospheric neutrinos in the Mont Blanc experiment

In the NUSEX experiment, during 2.8 years of operation, 31 fully contained events have been collected; 3 among them are nucleon decay candidates, while the others have been attributed to upsilon interactions. Limits on nucleon lifetime and determinations of upsilon interaction rates are presented

Primary cosmic ray spectrum in the 10 to the 12th power - 10 to the 16th power eV energy range from the NUSEX experiment

A primary cosmic ray spectrum was derived which fits both experimental multiple muon rates and the all-nucleon flux derived from the single muon intensities underground. In the frame of the interaction model developed by Gaisser, Elbert and Stanev, it is possible to reproduce NUSEX muon data with a primary composition in which the iron spectrum is only slightly flatter than the proton one. This result rules out the popular idea that the primary composition varies drastically with increasing energy, leading to the dominance of heavier nuclei at energies 10 to the 15th power to 10 to the 16th power eV

A simple method for the production of large volume 3D macroporous hydrogels for advanced biotechnological, medical and environmental applications

The development of bulk, three-dimensional (3D), macroporous polymers with high permeability, large surface area and large volume is highly desirable for a range of applications in the biomedical, biotechnological and environmental areas. The experimental techniques currently used are limited to the production of small size and volume cryogel material. In this work we propose a novel, versatile, simple and reproducible method for the synthesis of large volume porous polymer hydrogels by cryogelation. By controlling the freezing process of the reagent/polymer solution, large-scale 3D macroporous gels with wide interconnected pores (up to 200??m in diameter) and large accessible surface area have been synthesized. For the first time, macroporous gels (of up to 400?ml bulk volume) with controlled porous structure were manufactured, with potential for scale up to much larger gel dimensions. This method can be used for production of novel 3D multi-component macroporous composite materials with a uniform distribution of embedded particles. The proposed method provides better control of freezing conditions and thus overcomes existing drawbacks limiting production of large gel-based devices and matrices. The proposed method could serve as a new design concept for functional 3D macroporous gels and composites preparation for biomedical, biotechnological and environmental applications

The operator product expansion on the lattice

We investigate the Operator Product Expansion (OPE) on the lattice by directly measuring the product (where J is the vector current) and comparing it with the expectation values of bilinear operators. This will determine the Wilson coefficients in the OPE from lattice data, and so give an alternative to the conventional methods of renormalising lattice structure function calculations. It could also give us access to higher twist quantities such as the longitudinal structure function F_L = F_2 - 2 x F_1. We use overlap fermions because of their improved chiral properties, which reduces the number of possible operator mixing coefficients.Comment: 7 pages, 4 postscript figures. Contribution to Lattice 2007, Regensbur

Nucleon structure in terms of OPE with non-perturbative Wilson coefficients

Lattice calculations could boost our understanding of Deep Inelastic Scattering by evaluating moments of the Nucleon Structure Functions. To this end we study the product of electromagnetic currents between quark states. The Operator Product Expansion (OPE) decomposes it into matrix elements of local operators (depending on the quark momenta) and Wilson coefficients (as functions of the larger photon momenta). For consistency with the matrix elements, we evaluate a set of Wilson coefficients non-perturbatively, based on propagators for numerous momentum sources, on a 24^3 x 48 lattice. The use of overlap quarks suppresses unwanted operator mixing and lattice artifacts. Results for the leading Wilson coefficients are extracted by means of Singular Value Decomposition.Comment: 7 pages, 3 figures, contribution to the XXVI International Symposium on Lattice Field Theory, July 14-19 Williamsburg, Virginia, US

The late holocene evolution of coastal wetlands in Argyll, Western Scotland

A detailed geochronological and geochemical study has been undertaken on selected sediment cores from four lowland coastal marsh environments in Argyll, Western Scotland. This region of northern Britain has experienced differential crustal uplift and relative sea-level changes throughout the Holocene in response to glacio-isostatic adjustment. The complex interplay between land movements and relative sea-level continues to influence the morphological development of the Scottish coast. The study of lowland inter-tidal sedimentary environments from this region provides an opportunity to investigate the linkages between current estimated crustal movements, regional relative sea-level rise and the evolution of contemporary coastal saltmarshes derived from the record of historical sedimentation. The four sites are located across a ca. 70 km transect extending from the head of Loch Scridain (western Isle of Mull), across the Firth of Lorne to the head of Loch Etive, (mainland Argyll). Vertical activity distributions of the natural radionuclide 21OPb and anthropogenic isotopes (137Cs and 243Am) have been measured and are used to assess the depositional history of marsh sediment accumulation recorded in the four marsh cores. Down-core activity profiles of radionuclides are only reliable as a means of modelling recent marsh evolution provided no early-diagenetic (redox) reactions have compromised the historical depositional record within the marsh sediments. Solid-phase major and trace element down-core geochemical distributions provide a means of assessing the extent to which post-depositional (redox) reactions may have influenced the reliability of the radiometric dating methods. Marsh sediment geochemistry also serves as a useful proxy for identifying compositional variability over the period of marsh development investigated. Dating of the Argyll saltmarsh cores indicates that over the period corresponding to mature marsh conditions rates of sedimentation vary significantly across the study area. At Loch Scridain an average rate of 1.1 mm yr-1 corresponding to an historical period of ca. 130 years is recorded. Comparison with estimated rates of regional sea-level rise suggest an established asymptotic relationship between marsh accretion and coastal forcing, implying historical crustal stability at this site. At sites within the Firth of Lome (Loch Don and Loch Creran) average rates of 2.5 and 3.3 mm yr-1 are recorded for the ca. 70 year period to 1995 with a figure of 2.2 mm yr-1 recorded in the marsh core from the head of Loch Etive. These values are well in excess of estimated relative sea-level rise during the twentieth century suggesting that these marshes may not yet have reached full equilibrium with sea-level. Microfossil analysis of the Loch Etive core helps to identify a more complex depositional history with an underlying trend of marine transgression for the ca. 110 year period of marsh development recorded in these sediments. Over the most recent period of marsh development (ca. 5 years) a significant increase in the rate of marsh sedimentation at all sites is recorded. This signifies the response of these marshes to a very recent increase in the rate of relative sea-level rise across the region. Comparison with available storm frequency data indicates that the evolution of these marsh environments have not been subject to the influence of significant storm activity over the last in the late Twetieth century. The findings suggest that the more clastic sedimentary composition of the Argyll marshes results in these inter-tidal areas being extremely sensitive to changes in coastal forcing (sea-level rise). The implications of recent relative sea-level rise, current vertical crustal movements and future coastal management are discussed.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

The liquid krypton calorimeter cryogenics for the NA48 experiment

The NA48 cryogenic system has to provide stable thermal conditions (120 K) in a 9000 liter liquid krypton calorimeter, and has to ensure safe and loss free storage of the liquid during idle periods. Direct cooling of the krypton by nitrogen is used in emergency cases, while an intermediate cooler, containing saturated liquid argon at around 10 bar (117 K) is used under normal operation conditions when high thermal stability is needed. The krypton pressure is, during data taking, regulated to a value of (1.05 $\pm$ 0.01) bar for a period of about 8 months of continuous operation of the calorimeter