Improved Probability Method for Estimating Signal in the Presence of Background

A suggestion is made for improving the Feldman Cousins method of estimating signal counts in the presence of background. The method concentrates on finding essential information about the signal and ignoring extraneous information about background. An appropriate method is found which uses the condition that the number of background events obtained does not exceed the total number of events obtained. Several alternative approaches are explored.Comment: Modified 12/21 for singlespace to save trees, 9 pages, 1 figure. Modified 8/11/99 to add small modifications made for the Phys. Rev. articl

Neutrino Masses and Mixing one Decade from Now

We review the status of neutrino masses and mixings in the light of the solar and atmospheric neutrino data. The result from the LSND experiment is also considered. We discuss the present knowledge and the expected sensitivity to the neutrino mixing parameters in the simplest schemes proposed to reconcile these data some of which include a light sterile neutrino in addition to the three standard ones.Comment: 16 pages Latex file using elsart.sty. Seven postscript figures included. Talk given at the ICFA/ECFA Workshop "Neutrino Factories based on Muon Storage Rings, nu-FACT99", Lyon, July 1999. Typo in Eq. 8 correcte

How degenerate can cosmological neutrinos be?

There are well-known bounds on light neutrino masses from cosmological energy density arguments. These arguments assume the neutrinos to be non-degenerate. We show how these bounds are affected if the neutrinos are degenerate. In this case, we obtain correlated bounds between neutrino mass and degeneracy.Comment: 5 pages, Latex, uses epsf.sty. (Some details added at the referee's request. One reference added.

Four species neutrino oscillations at ν\nu-Factory: sensitivity and CP-violation

The prospects of measuring the leptonic angles and CP-odd phases at a {\em neutrino factory} are discussed in the scenario of three active plus one sterile neutrino. We consider the \nu_\mu \raw \nu_e LSND signal. Its associated large mass difference leads to observable neutrino oscillations at short ($\sim 1$ km) baseline experiments. Sensitivities to the leptonic angles down to $10^{-3}$ can be easily achieved with a 1 Ton detector. Longer baseline experiments ($\sim 100$ km) with a 1 Kton detector can provide very clean tests of CP-violation especially through tau lepton detection.Comment: 15 pages, LaTeX2e, 14 eps files, use package epsfi

Pointwise recurrent homeomorphisms with stable fixed points

AbstractWe prove that a pointwise recurrent, orientation preserving homeomorphism of the 2-sphere, which is different from the identity and whose fixed points are stable in the sense of Lyapunov must have exactly two fixed points. If moreover there are no periodic points, other than fixed, then every stable minimal set is connected and its complement has exactly two connected components. Finally, we study liftings of the restriction to the complement of the fixed point set to the universal covering space

Status of the MINOS experiment

I will present the status of the long baseline neutrino oscillation experiment MINOS at Fermi National Accelerator Laboratory (Fermilab). I will summarize the status of the detector and beam construction, the expected event rates and sensitivity to physics. I will also comment on possible future plans to improve the performance of the experiment.Comment: Invited talk at the Seventh International Workshop on Tau Lepton Physics (TAU02), Santa Cruz, Ca, USA, Sept 2002, 7 pages, 6 figures, LaTeX Higher res figures at http://minos.phy.bnl.gov/~diwan/tau02_th08.p

Neutrino Oscillation Search at MiniBooNE

This article reports the status of a $\nu_{\mu} \to \nu_{e}$ oscillation search in MiniBooNE (Booster Neutrino Experiment) experiment. If an appearance signal is observed, it will imply Physics Beyond the Standard Model such as the existence of light sterile neutrino.Comment: 6 pages, 4 figures. Plenary talk at the Neutrino Oscillation Workshop (NOW2006), September 2006, to be published in Nucl.Phys. B (Proc. Suppl.

Charged-current neutrino-208Pb reactions

We present theoretical results on the non flux-averaged $^{208}Pb(\nu_{e},e^-)^{208}Bi$ and $^{208}Pb(\nu_{\mu},\mu^-)^{208}Bi$ reaction cross sections, obtained within the charge-exchange Random-Phase-Approximation. A detailed knowledge of these cross sections is important in different contexts. In particular, it is necessary to assess the possibility of using lead as a detector in future experiments on supernova neutrinos, such as OMNIS and LAND, and eventually detect neutrino oscillation signals by exploiting the spectroscopic properties of $^{208}Bi$. We discuss the present status on the theoretical predictions of the reaction cross sections.Comment: 5 pages, latex, 3 figures. added discussion on present status, Submitted to Phys.Rev.

Disentangling Within- and Between-Country Efficiency Differences of Bank Branches

In this paper we propose a framework to assess the efficiency of bank branch networks operating in different financial environments. The framework can be used to disentangle within- from between-country performance differences. The framework is constructive in that it identifies operational aspects responsible for superior performance and suggests guidelines for branch improvement. We report results from three bank branch networks in the U.K., Greece and Cyprus, and demonstrate how branch networks can benefit from such international comparisons.Bank Branch Efficiency, International Benchmarks, Data Envelopment Analysis.

A See-saw model of sterile neutrino

If the smallness of the mass of the sterile neutrino is to be explained by the see-saw mechanism, the off-diagonal entries of the mass matrix needs to be protected by some symmetry not far above the electroweak scale. We implement see-saw mechanism in a gauge model based on $SU(2)^q_L \times SU(2)^l_L \times U(1)^q_Y \times U(1)^l_Y$ un-unified gauge group which breaks to $SU(2)_L \times U(1)_Y$ at the TeV region via a two-step symmetry breaking chain. The right handed diagonal block is tied to the highest scale up to which the un-unification symmetry holds. The sterile neutrino emerges from a quark-lepton mixed representation of the un-unified group.Comment: Revised version, to appear in Phys. Lett.