110934427
Experience in construction and testing of plastic limited streamer chambers
The manufacture and testing of multicell limited streamer chambers for use in the hadron calorimeter of the OPAL detector and LEP (Large Electron Positron Collider) are described. All operations, from chamber cathode coating to the testing of completed subassemblies, have been performed under the same roof. With reasonable care and quality control, the established technology produced chambers several meters long with an overall success rate of about 90%. Treatment of the carbon coating with Breox B-35 was effective in eliminating uncertainties in the cathode performance. >
117245675
Ultra High Energy nt Detection Using Air Shower Fluorescence/Cerenkov Light Detector
The possibility of using air shower fluorescence/Cerenkov light detectors for ντ detection has been explored. A detector of this type is proposed to be set in the shadow of Mt. Wheeler Peak in Nevada, USA. The ντ to shower conversion probability density is calculated over an energy range from 1 PeV to 10 EeV. The number of showers converted from ντ ’s are estimated according to several models of neutrino sources.
26918473
Geometry and optics calibration for air fluorescence detectors using star light
Abstract The high resolution Fly’s Eye (HiRes) detector in Dugway, Utah, is an air fluorescence detector designed for the measurement of the energy and arrival direction of cosmic ray particles with energy E >10 18 eV. HiRes monitors the night sky for fluorescence light from air shower cascades induced by cosmic ray primaries. The light is collected by mirrors and projected onto arrays of photomultiplier tubes that provide an image of the air shower. HiRes is an astronomical instrument, and the accuracy of the mirror pointing and understanding of the optical properties of the mirror–camera units is crucial. We present a method to cross-check and monitor the mirror pointing by using star light. A star crossing the field of view of a photomultiplier tube causes a temporary increase in the total light detected by the tube. Using UV bright stars, we analyze the pointing accuracy of the HiRes 2 detector, and evaluate the shape of a point-like object as a function of distance to the mirror axis.
15877362
A fiber-optic-based calibration system for the High Resolution Fly's Eye cosmic ray observatory
Abstract This article describes the fiber-optic-based calibration system installed at the High Resolution Fly's Eye (HiRes) astro-particle physics observatory. The HiRes detectors measure ultra violet scintillation light from distant extensive air showers. This automated calibration system delivers light from a frequency tripled 355 nm YAG laser to the 10,752 photo-multiplier tubes of the 42 HiRes-II detectors.
124185401
Status of the High Altitude Water Cherenkov (HAWC) gamma ray observatory
128530951
Site Characteristics of Southern Utah Sites for Astronomical Observatories
The University of Utah has recently begun construction of a new 0.8 m optical/IR robotic telescope to be operated as a regional astronomy resource in the Intermountain West. The new Southern Utah Observatory (SUO) will require a high altitude (>3000 m) site with excellent atmospheric seeing, favorable weather conditions, and nearby infrastructure, including road, power, and high speed internet. We have explored six possible sites for the SUO telescope with favorable climate, night sky darkness and infrastructure. Since spring 2007, we have performed detailed measurements of atmospheric seeing at several of these sites, and have identified the preferred site for the SUO telescope at Frisco Peak, UT. Several large (1 sq. mile) areas of State Trust Land are nearby the new SUO telescope site. These large, flat areas may be excellent sites for large area, next generation Imaging Atmospheric Cherenkov Telescopes (IACT) arrays such as AGIS or northern CTA.
14207492
Hyperon Decays in Chiral Perturbation Theory Revisited
The discrepancies found between S-wave and P-wave fits for hyperon decays are reinvestigated using the heavy baryon chiral Lagrangian formalism. 
The agreement is found to improve through the inclusion of previously omitted diagrams. The S-waves are unaffected by this, but the P-wave predictions are modified. A correlated fit to the chiral parameters is performed and the results discussed.
32623279
Heavy-Quark Symmetry and the Electromagnetic Decays of Excited Charmed Strange Mesons
Heavy-hadron chiral perturbation theory (HH{chi}PT) is applied to the decays of the even-parity charmed strange mesons, D{sub s0}(2317) and D{sub s1}(2460). Heavy-quark spin-symmetry predicts the branching fractions for the three electromagnetic decays of these states to the ground states D{sub s} and D{sub s}* in terms of a single parameter. The resulting predictions for two of the branching fractions are significantly higher than current upper limits from the CLEO experiment. Leading corrections to the branching ratios from chiral loop diagrams and spin-symmetry violating operators in the HH{chi}PT Lagrangian can naturally account for this discrepancy. Finally the proposal that the D{sub s0}(2317) (D{sub s1}(2460)) is a hadronic bound state of a D(D*) meson and a kaon is considered. Leading order predictions for electromagnetic branching ratios in this molecular scenario are in very poor agreement with existing data.
119535257
Heavy baryon chiral perturbation theory and the weak nonleptonic p-wave decays of the baryon octet
Abstract Considerable confusion in the literature about heavy baryon chiral perturbation theory, its convergence properties, and appropriate calculational techniques, make it timely to discuss the nonleptonic p-wave decays of the octet of baryons. We present model independent results.
56337141
Parity-violating neutron spin rotation in hydrogen and deuterium
AbstractWe calculate the (parity-violating) spin-rotation angle of a polarized neutron beam through hydrogen and deuterium targets, using pionless effective field theory up to next-to-leading order. Our result is part of a program to obtain the five leading independent low-energy parameters that characterize hadronic parity violation from few-body observables in one systematic and consistent framework. The two spin-rotation angles provide independent constraints on these parameters. Our result for np spin rotation is $$\frac{1}
{\rho }\frac{{d\varphi _{PV}^{np} }}
{{dl}} = \left[ {4.5 \pm 0.5} \right] rad MeV^{ - \frac{1}
{2}} \left( {2g^{\left( {^3 S_1 - ^3 P_1 } \right)} + g^{\left( {^3 S_1 - ^3 P_1 } \right)} } \right) - \left[ {18.5 \pm 1.9} \right] rad MeV^{ - \frac{1}
{2}} \left( {g_{\left( {\Delta {\rm I} = 0} \right)}^{\left( {^1 S_0 - ^3 P_0 } \right)} - 2g_{\left( {\Delta {\rm I} = 2} \right)}^{\left( {^1 S_0 - ^3 P_0 } \right)} } \right)$$, while for nd spin rotation we obtain $$\frac{1}
{\rho }\frac{{d\varphi _{PV}^{nd} }}
{{dl}} = \left[ {8.0 \pm 0.8} \right] rad MeV^{ - \frac{1}
{2}} g^{\left( {^3 S_1 - ^1 P_1 } \right)} + \left[ {17.0 \pm 1.7} \right] rad MeV^{ - \frac{1}
{2}} g^{\left( {^3 S_1 - ^3 P_1 } \right)} + \left[ {2.3 \pm 0.5} \right] rad MeV^{ - \frac{1}
{2}} \left( {3g_{\left( {\Delta {\rm I} = 0} \right)}^{\left( {^1 S_0 - ^3 P_0 } \right)} - 2g_{\left( {\Delta {\rm I} = 1} \right)}^{\left( {^1 S_0 - ^3 P_0 } \right)} } \right)$$, where the g(X-Y), in units of $$MeV^{ - \frac{3}
{2}}$$, are the presently unknown parameters in the leading-order parity-violating Lagrangian. Using naıve dimensional analysis to estimate the typical size of the couplings, we expect the signal for standard target densities to be $$\left| {\frac{{d\varphi _{PV} }}
{{dl}}} \right| \approx \left[ {10^{ - 7} \ldots 10^{ - 6} } \right]\frac{{rad}}
{m}$$ for both hydrogen and deuterium targets. We find no indication that the nd observable is enhanced compared to the np one. All results are properly renormalized. An estimate of the numerical and systematic uncertainties of our calculations indicates excellent convergence. An appendix contains the relevant partial-wave projectors of the three-nucleon system.
85525002
The Theory of Parity Violation in Few-Nucleon Systems
Abstract We review recent progress in the theoretical description of hadronic parity violation in few-nucleon systems. After introducing the different methods that have been used to study parity-violating observables we discuss the available calculations for reactions with up to five nucleons. Particular emphasis is put on effective field theory calculations where they exist, but earlier and complementary approaches are also presented. We hope this review will serve as a guide for those who wish to know what calculations are available and what further calculations need to be completed before we can claim to have a comprehensive picture of parity violation in few nucleon systems.