Search Results (7 total)

We describe the status of our effort to realize a first neutrino factory and the progress made in understanding the problems associated with the collection and cooling of muons towards that end. We summarize the physics that can be done with neutrino factories as well as with intense cold beams of muons. The physics potential of muon colliders is reviewed, both as Higgs factories and compact high-energy lepton colliders. The status and time scale of our research and development effort is reviewed as well as the latest designs in cooling channels including the promise of ring coolers in achieving longitudinal and transverse cooling simultaneously. We detail the efforts being made to mount an international cooling experiment to demonstrate the ionization cooling of muons.

We analyze the prospects of a feasible, Brookhaven National Laboratory based, very long baseline neutrino oscillation experiment consisting of a conventional horn produced low energy wideband beam and a detector of 500 kton fiducial mass with modest requirements on event recognition and resolution. Such an experiment is intended primarily to determine CP violating effects in the neutrino sector for 3-generation mixing. We analyze the sensitivity of such an experiment. We conclude that this experiment will allow determination of the CP phase δ_CP and the currently unknown mixing parameter θ₁₃, if sin²2θ₁₃>~0.01, a value ∼15 times lower than the present experimental upper limit. In addition to θ₁₃ and δ_CP, the experiment has great potential for precise measurements of most other parameters in the neutrino mixing matrix including Δm₃₂², sin²2θ₂₃, Δm₂₁²×sin 2θ₁₂, and the mass ordering of neutrinos through the observation of the matter effect in the ν_μ→ν_e appearance channel.

The status of the research on muon colliders is discussed and plans are outlined for future theoretical and experimental studies. Besides work on the parameters of a 3–4 and 0.5 TeV center-of-mass (COM) energy collider, many studies are now concentrating on a machine near 0.1 TeV (COM) that could be a factory for the s-channel production of Higgs particles. We discuss the research on the various components in such muon colliders, starting from the proton accelerator needed to generate pions from a heavy-Z target and proceeding through the phase rotation and decay (π→μν_μ) channel, muon cooling, acceleration, storage in a collider ring, and the collider detector. We also present theoretical and experimental R&D plans for the next several years that should lead to a better understanding of the design and feasibility issues for all of the components. This report is an update of the progress on the research and development since the feasibility study of muon colliders presented at the Snowmass '96 Workshop [R. B. Palmer, A. Sessler, and A. Tollestrup, Proceedings of the 1996 DPF/DPB Summer Study on High-Energy Physics (Stanford Linear Accelerator Center, Menlo Park, CA, 1997)].

Rare kaon decays due to the loop-induced standard model operator s¯_Lγ_μd_Lν¯_Lγ^μν_L are examined. Isospin-violating mass effects and electroweak radiative corrections are shown to reduce B(K⁺→π⁺νν¯) and B(K_L→π⁰νν¯) relative to B(K⁺→π⁰e⁺ν_e) by 10% and 5.6%, respectively. Predicted branching ratios for (K_L→νν¯γ) and (K_L→νν¯) (if neutrinos have mass) are given. The sensitivity of ‘‘missing energy’’ rare K decays to new interactions or the emission of light weakly interacting neutral particles, other than neutrinos, is also briefly discussed. © 1995 The American Physical Society.

We propose a modified definition of hadronic jets in quantum chromodynamics which is more selective than the Sterman-Weinberg criterion. It prohibits any two jet streams from having appreciably different energies. Our more restrictive definition provides new tests of quantum chromodynamics in high-energy experiments. We illustrate this idea for two-"quark"-jet configurations in e⁺e^-→hadrons and for two-"gluon"-jet production. The necessity of exponentiating perturbative jet predictions is also discussed.

Energy spectra and spectroscopic factors of negative-parity states in ⁷¹Ge are calculated within the framework of the quasiparticle-vibration coupling approach in the unified nuclear model. The calculated results are in very good agreement with the experimental data.

NUCLEAR STRUCTURE ⁷¹Ge; calculated levels, J, π, and spectroscopic factors. Compared with experiments.

We demonstrate how the finite-energy unit magnetic monopole of an SU(2) gauge theory generalizes to configurations with multiple magnetic charge when properly embedded in higher-rank gauge theories. Masses and stability properties of these topologically distinct solutions are discussed. This same generalization is shown to hold for the pseudoparticle solution of Euclidean Yang-Mills theories. Finally, properties of the gravitational pseudoparticle solutions to the Einstein field equations are exhibited and discussed.