118361213
On the noncommutative fields method in the three-dimensional Yang-Mills theory
We apply the noncommutative fields method to the three-dimensional non-Abelian gauge theory. We find that, first, implementing the noncommutativity between the canonical momenta implies in generation of the non-Abelian Chern-Simons term, second, if one introduces the noncommutativity between the field operators, the higher derivative terms would arise.
119686840
On Aharonov–Casher scattering in a CPT-odd Lorentz-violating background
The effects of a Lorentz symmetry-violating background vector on Aharonov?Casher scattering in the nonrelativistic limit are considered. Using the self-adjoint extension method, we find that there is additional scattering for any value of the self-adjoint extension parameter and non-zero energy bound states for negative values of this parameter. Expressions for the energy bound states, phase-shift and scattering matrix are explicitly determined in terms of the self-adjoint extension parameter. The expression obtained for the scattering amplitude reveals that the helicity is not conserved in this scenario.
118609457
Relativistic Landau-Aharonov-Casher quantization based on the Lorentz symmetry violation background
Based on the discussions about the Aharonov-Casher effect in the Lorentz symmetry violation background, we show that the analogue of the relativistic Landau quantization in the Aharonov-Casher setup can be achieved in the Lorentz-symmetry violation background.
119697349
On the spin- 1/2 Aharonov-Bohm problem in conical space: Bound states, scattering and helicity nonconservation
In this work the bound state and scattering problems for a spin-1/2 particle undergone to an Aharonov-Bohm potential in a conical space in the nonrelativistic limit are consider ed. The presence of a �-function singularity, which comes from the Zeeman spin interaction with the magnetic flux tube, is addressed by the self-adjoint extension method. One of the advantages of the present approach is the determination of the self-adjoint extension parameter in terms of physics of the problem. Expressions for the energy bound states, phase-shift and S matrix are determined in terms of the self-adjoint extension parameter, which is explicitly determined in terms of the parameters of the problem. The relation between the bound state and zero modes and the failure of helicity conservation in the scattering problem and its relation with the gyromagnetic ratio g are discussed. Also, as an application, we consider the spin-1/2 AharonovBohm problem in conical space plus a two-dimensional isotropic harmonic oscillator.
119322655
Finiteness of the noncommutative supersymmetric Maxwell-Chern-Simons theory
Within the superfield approach, we prove the absence of UV/IR mixing in the three-dimensional noncommutative supersymmetric Maxwell-Chern-Simons theory at any loop order and demonstrate its finiteness in one, three, and higher loop orders.
118670238
He–McKellar–Wilkens effect and scalar Aharonov–Bohm effect for a neutral particle based on the Lorentz symmetry violation
In this contribution, we discuss the He–McKellar–Wilkens effect and the scalar Aharonov–Bohm effect for neutral particles based on the Lorentz symmetry violation background, by showing that the background of the Lorentz symmetry violation yields Abelian quantum phases for a neutral particle. We also study the non-relativistic bound states for a neutral particle interacting with a Coulomb-like potential based on the Lorentz symmetry violation background given by a fixed vector field parallel to the radial direction.
121825292
The Cryogenic Dark Matter Search (CDMS) : Present Status and Future
The CDMS collaboration utilizes Ge detectors for their Weakly Interacting Massive Particle (WIMP) search at the Soudan mine, Minnesota. The final data run of CDMS II is complete and a detector upgrade for SuperCDMS has commenced. A SuperTower of five 1‐inch thick Ge crystals has been installed and undergoing commissioning. Its surface‐event rejection capability should allow SuperCDMS to continue to run background free for the next proposed phases: 15 kg Ge deployment at Soudan, and up to 150 kg Ge deployment at SNOLAB. Recent detector advances to allow a 1 tonne Ge experiment are also discussed.
1529836
Search for a new gauge boson in π0 decays
Abstract A search was made for a new light gauge boson X which might be produced in π 0 → γ + X decay from neutral pions generated by 450 GeV protons in the CERN SPS neutrino target. The X's would penetrate the downstream shielding and be observed in the NOMAD detector via the Primakoff effect, in the process of X → π 0 conversion in the external Coulomb field of a nucleus. With 1.45×10 18 protons on target, 20 candidate events with energy between 8 and 140 GeV were found from the analysis of neutrino data. This number is in agreement with the expectation of 18.1±2.8 background events from standard neutrino processes. A new 90 % C.L. upper limit on the branching ratio Br ( π 0 → γ + X ) −5 for X masses ranging from 0 to 120 MeV/ c 2 is obtained.
39304411
Strange baryon production in hadronic Z0 decays
53499025
Performance of the NOMAD-STAR detector
The NOMAD-STAR detector is a silicon vertex installed in the NOMAD spectrometer at the CERN SPS neutrino beam. It consists of four layers of a passive boron carbide target with a total mass of 45 kg and five layers of 600 single sided silicon microstrip detectors covering a total area of 1.14m^2. About 11,500 nu_mu charged current interactions were reconstructed in the fiducial volume of NOMAD-STAR from the neutrino run in 1998. The potential use of silicon detectors for nu_mu (nu_e) nu_tau oscillations depends on the observation of the tau candidates by the experimental signature of a large impact parameter, in the case of the one prong decay of the tau, or a double vertex, in the case of the three prong decay. The main aim of NOMAD-STAR is to measure the impact parameter and vertex distributions of charged current interactions, which constitute the main backgrounds for the oscillation signals, to understand the significance of a potential signal in a future experiment. The present paper describes the experience gained in the operation of this silicon vertex detector, and the peformance achieved with it.
116534437
An improved measurement of R-b using a double tagging method