Search results for "MINOS"
showing 10 items of 739 documents
Performance of the MIND detector at a Neutrino Factory using realistic muon reconstruction
2010
A Neutrino Factory producing an intense beam composed of v(e)((v) over bar (e)) and (v) over bar (mu)(v(mu)) from muon decays has been shown to have the greatest sensitivity to the two currently unmeasured neutrino mixing parameters theta(13) and delta(CP) Using the wrong-sign muon signal to measure v(e)-> v(mu)((v) over bar (e) ->(v) over bar (mu)) oscillations in a 50kt Magnetised Iron Neutrino Detector (MIND) sensitivity to delta(CP) could be maintained down to small values of theta(13) However the detector efficiencies used in these previous studies were calculated assuming perfect pattern recognition In this paper MIND is reassessed taking into account for the first time a realistic pa…
Measurement of σ(pp¯→Z+X)Br(Z→τ+τ−) at s=1.96 TeV
2009
We present a measurement of the cross section for Z boson production times the branching fraction to tau lepton pairs sigma(p (p) over bar -> Z + X)Br(Z -> tau(+)tau(-)) in p (p) over bar collisions at root s = 1.96 TeV. The measurement is performed in the channel in which one tau lepton decays into a muon and neutrinos. and the other tau lepton decays hadronically or into an electron and neutrinos. The data sample corresponds to an integrated luminosity of 1.0 fb(-1) collected with the DO detector at the Fermilab Tevatron Collider. The sample contains 1511 candidate events with an estimated 20% background from jets or muons misidentified as tau leptons. We obtain sigma . Br = 240 +/- 8 (st…
Inclusive J/ψ production in pp collisions at s=2.76 TeV
2012
The ALICE Collaboration has measured inclusive J/psi production in pp collisions at a center of mass energy sqrt(s)=2.76 TeV at the LHC. The results presented in this Letter refer to the rapidity ranges |y|<0.9 and 2.5
Early results of the LHCf experiment and their contribution to ultra-high-energy cosmic ray physics
2010
LHCf is an experiment dedicated to the measurement of neutral particles emitted in the very forward region of LHC collisions. The physics goal is to provide data for calibrating hadron interaction models that are used in the study of Extremely High-Energy Cosmic-Rays. The LHCf experiment acquired data from April to July 2010 during commissioning time of LHC operations at low luminosity. Production spectra of photons and neutrons emitted in the very forward region ($��>$ 8.4) have been obtained. In this paper preliminary results of the photon spectra taken at $\sqrt{s}$ = 7TeV are reported.
Use of an FPGA to identify electromagnetic clusters and isolated hadrons in the ATLAS level-1 calorimeter trigger
2003
Abstract At the full LHC design luminosity of 10 34 cm −2 s −1 , there will be approximately 109 proton–proton interactions per second. The ATLAS level-1 trigger is required to have an acceptance factor of ∼10−3. The calorimeter trigger covers the region |η|⩽5.0, and φ=0 to 2π. The distribution of transverse energy over the trigger phase space is analysed to identify candidates for electrons/photons, isolated hadrons, QCD jets and non-interacting particles. The Cluster Processor of the level-1 calorimeter trigger is designed to identify transverse energy clusters associated with the first two of these. The algorithms based on the trigger tower energies which have been designed to identify s…
Measurement of theB→Xsγbranching fraction and photon energy spectrum using the recoil method
2008
We present a measurement of the branching fraction and photon-energy spectrum for the decay B -> X-s gamma using data from the BABAR experiment. The data sample corresponds to an integrated luminosity of 210 fb(-1), from which approximately 680 000 B (B) over bar events are tagged by a fully reconstructed hadronic decay of one of the B mesons. In the decay of the second B meson, an isolated high-energy photon is identified. We measure B(B -> X-s gamma) = (3.66 +/- 0.85(stat) +/- 0.60(syst)) x 10(-4) for photon energies E-gamma above 1.9 GeV in the B rest frame. From the measured spectrum we calculate the first and second moments for different minimum photon energies, which are used to extra…
Search forZγevents with large missing transverse energy inpp¯collisions ats=1.96 TeV
2012
We present the first search for new phenomena in Z gamma final states with large missing transverse energy using data corresponding to an integrated luminosity of 6.2 fb(-1) collected with the D0 experiment in p (p) over bar collisions at root s 1.96 TeV. This signature is predicted in gauge-mediated supersymmetry-breaking models, where the lightest neutralino (chi) over tilde (0)(1) is the next-to-lightest supersymmetric particle and is produced in pairs, possibly through decay from heavier supersymmetric particles. The (chi) over tilde (0)(1) can decay either to a Z boson or a photon and an associated gravitino that escapes detection. We exclude this model at the 95% C.L. for supersymmetr…
Zγproduction and limits on anomalousZZγandZγγcouplings inpp¯collisions ats=1.96 TeV
2012
We present a measurement of ppbar->Zgamma->ll+gamma (l = e, mu) production with a data sample corresponding to an integrated luminosity of 6.2 fb^{-1} collected by the D0 detector at the Fermilab Tevatron ppbar Collider. The results of the electron and muon channels are combined, and we measure the total production cross section and the differential cross section dsigma/dp_T^gamma, where p_T^gamma is the momentum of the photon in the plane transverse to the beamline. The results obtained are consistent with the standard model predictions from next-to-leading order calculations. We use the transverse momentum spectrum of the photon to place limits on anomalous ZZgamma and Zgammagamma couplin…
Neutrinos that violate CPT, and the experiments that love them
2002
Recently we proposed a framework for explaining the observed evidence for neutrino oscillations without enlarging the neutrino sector, by introducing CPT violating Dirac masses for the neutrinos. In this paper we continue the exploration of the phenomenology of CPT violation in the neutrino sector. We show that our CPT violating model fits the existing SuperKamiokande data at least as well as the standard atmospheric neutrino oscillation models. We discuss the challenge of measuring CP violation in a neutrino sector that also violates CPT. We point out that the proposed off-axis extension of MINOS looks especially promising in this regard. Finally, we describe a method to compute CPT violat…
Can OPERA help in constraining neutrino non-standard interactions?
2008
We study how much the unique ability of the OPERA experiment to directly detect \nu_\tau can help in probing new, non-standard contact interactions of the third family of neutrinos. We perform a combined analysis of future, high-statistics MINOS and OPERA data. For the case of non-standard interactions in \nu_\mu to \nu_e transitions we also include the impact of possible DoubleCHOOZ data. In all cases we find that the \nu_\tau sample of OPERA is too small to be statistically significant, even if one doubles the nominal exposure of OPERA to 4.5E20 pot. OPERA's real benefit for this measurement lies in its very high neutrino energy and hence very different L/E compared to MINOS.