120224392
The effects of neutron irradiation on multi-pixel hybrid photodiode tubes
Abstract The effects of neutron irradiation on a multi-pixel hybrid photodiode tube (HPD) were studied. The HPD underwent an integrated fluence of 10 13 neutrons cm 2 from a 252 Cf source. Increased leakage currents were observed during this irradiation, consistent with that observed from bare silicon detectors. The HPD was observed to be fully operational, with acceptable leakage currents, at the fluences expected during the lifetime of the CMS experiment. After the full dosage, small intrapixel inhomogeneities were observed in the HPD's response. The origins of these inhomogeneities and methods to mitigate the radiation damage were investigated.
122041574
Multi-pixel hybrid photodiode tubes for the CMS hadron calorimeter
Abstract Avalanche Photodiodes and 7-channel HPDs from DEP were installed on a prototype CMS HCAL and their response to muons, electrons and pions was measured in a test beam. DC response to a radioactive source used to calibrate the tiles was also studied. Increase in leakage current in the HPD from an integrated dose of 10 13 neutrons/cm 2 was observed using a Cf source.
199679707
Measurement of muon plus proton final states in $\nu_{\mu}$ Interactions on Hydrocarbon at $ $ = 4.2 GeV
108864186
MINOS near-detector coil design
The 980-ton MINOS near detector will be installed in the new NuMI near hall at 100m below grade at Fermilab. It will be assembled from 282 1-inch thick steel plates. The planes are made from low carbon (1006), hot rolled steel and are toroidally magnetized. Each plane will be hung by two 'ears', which are extensions of the octagonal plane structure, similar to the hanging files in a file drawer. The plates have a center-to-center spacing of 5.94 cm. This document has been prepared for the 8/99 Conceptual Design Review of the MINOS near detector coil. It's main goal is to provide a set of references to previous documents and to assemble various design drawings and engineering calculations that have not been included in previous technical memos. It also provides some background material relevant for the coil implementation. Much of the text for this document is edited from the MINOS Detectors Technical Design Report.
42871335
Search for exclusive b-->u semileptonic decays of B mesons.
Using a sample of 935000 BB pairs collected with the CLEO-II detector at the Cornell Storage Ring, we have obtained upper limits on the branching ratios for the b→ul - υ#58 processes B - →ωl - υ#58, B - →ρ 0 l - υ#58, and B 0 →ρ + l - υ#58. The combined result using the relationships among the widths for these three modes is B(B - →ρ 0 l - υ#58)<(1.6-2.7)×10 -4 at 90% C. L., where the range of value to model dependence of the detection efficiencies. These measurements yield the limits |V ub /V cb |<0.08-0.13
119509119
The MINOS Magnets
The MINOS long baseline neutrino oscillation experiment will consists of two magnetized tracking calorimeters one on the Fermilab site and one in Minnesota. This paper summarizes the design, magnetic performance, and status of the MINOS magnets.
121073474
Homotopy groups and (2+1)-dimensional quantum de Sitter gravity
Abstract The integrated CCR (canonical commutation relations) for (2 + 1)-dimensional de Sitter/ anti-de Sitter gravity in first-order formalism are used to derive generalised spinor representations Ψ: π 1 (Σ) → SL (2, C )/ SL (2, R ) ⊗ SL (2, R ) of the fundamental group of the initial data surface Σ 2 . The matrix elements of Ψ ( U ), Ψ ( V ), with U ≠ V are in general non-commuting according to a set of formal rules which are related to the theory of quantum groups. The Poincare theory appears as a limiting case.
122207192
Homotopy Groups and (2+1)-dimensional Quantum Gravity
The integrated CCR (canonical commutation relations) for 2+1 dimensional gravity in the vielbein first order formalism are used to derive generalised representations Ψ: π1 (Σ) → ISO(2, 1) of the fundamental group of the initial data surface Σ2. The matrix elements of Ψ(U), Ψ(V), where U≠V are in general non-commuting according to a set of well-defined formal rules.
120048132
Canonical normal coordinates
We examine the advantages and disadvantages of fixing the coordinate gauge to be that of the Riemann normal coordinates by applying the Dirac formalism for constrained canonical systems in general relativity.
123231602
Covariant canonical formalism for the group manifold
A canonical formalism is developed for the exterior calculus on differential forms using the group manifold approach. The formalism is naturally invariant under coordinate transformations, i.e., there is no preferred time direction. The Lagrangian density is again found to be degenerate and we discuss the resulting constraints a la Dirac. The Hamiltonian formalism is introduced using a bracket operation, defined for differential forms.
120746763
The group manifold hamiltonian for supergravity
Abstract We establish the correspondence between the covariant canonical formalism for N = 1 supergravity and the component formalism. Throughout we use a compound Poincare notation extended to include spinor components, and find the structure of the hamiltonian and constraint algebra identical with that of pure gravity, differing only in the range of the compound indices.