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Detector R&D for future neutrino experiments with the NuMI beamline.

Description: This document is the result of a request from the Fermilab directorate to (i) investigate the detector technology issues relevant for future long baseline experiments and (ii) consider the associated detector R and D that would be needed to prepare the way for future neutrino oscillation experiments using the NuMI beamline. Because of the narrow energy spread provided by an off-axis beam and the resulting low intrinsic electron neutrino background, as well as the very favorable duty cycle of the NuMI beamline, a well-placed neutrino detector at the surface of the earth could take the next important steps in neutrino oscillation physics. The biggest outstanding issue in this field is whether or not the last unmeasured element of the leptonic mixing matrix, parameterized by the mixing angle {theta}{sub 13}, is nonzero. If it is in fact non-zero, this opens the door to measurements of the neutrino mass hierarchy and, if the solar neutrino oscillations are described by the LMA solution, searches for CP violation in the lepton sector. In order to get to any of these measurements, an off-axis detector must be capable of measuring the {nu}{sub {mu}}({bar {nu}}{sub {mu}}) {yields} {nu}{sub e}({bar {nu}}{sub e}) transition probabilities as well as the {nu}{sub {mu}}({bar {nu}}{sub {mu}}) survival probabilities, at the energies present in these off-axis beams, which could lie anywhere from 0.6 to 3 GeV. Optimal baselines and energies will depend on the physics goal of the experiment. For example, an optimization of the sensitivity for {nu}{sub e} appearance from a {nu}{sub {mu}} beam assuming {Delta}m{sub 32}{sup 2} = 3 x 10{sup -3} eV{sup 2} would lead to a baseline of {approx} 700-900 km and an energy of {approx} 2.2 GeV.
Date: July 25, 2003
Creator: Drake, G.; Goodman, M.; Bareboim, G.; Bodek, A.; Bross, A.; Buckley-Geer, L. et al.
Partner: UNT Libraries Government Documents Department

Letter on intent to build an off-axis detector to study {nu}{sub mu}{yields}{nu}{sub e} oscillations with the NuMI neutrino beam. Version 6.0

Description: The question of neutrino masses is of fundamental importance. Neutrino oscillations seem to be the only tool available to us to unravel the pattern of neutrino masses and, perhaps, shed some light on the origin of masses in general. The NuMI neutrino beam line and the MINOS experiment represent a major investment of US High Energy Physics in the area of neutrino physics. the forthcoming results could decisively establish neutrino oscillations as the underlying physics mechanism for the atmospheric {nu}{sub {mu}} deficit and provide a precise measurement of the corresponding oscillation parameters, {Delta}m{sub 32}{sup 2} and sin{sup 2} 2{theta}{sub 23}. This, however, is just a beginning of a long journey into uncharted territories. The key to these new territories is the detection of {nu}{sub {mu}} {yields} {nu}{sub e} oscillations associated with the atmospheric {nu}{sub {mu}} deficit, controlled by the little known mixing angle sin{sup 2}2{theta}{sub 13}. A precise measurement of the amplitude of these oscillations will enable a determination of the pattern of the mass hierarchy of neutrinos. If the solar neutrino experiments determine that the value {Delta}m{sub 12}{sup 2} is in the range of 10{sup -5}-10{sup -4} eV{sup 2} then the measurement of the CP violation in the neutrino sector may well be within our reach. The full potential of the NuMI neutrino beam can be exploited by complementing the MINOS detector, under construction, with a new detector(s) placed at some off-axis position and collecting data in parallel with MINOS. The first phase of the proposed program includes a new detector, optimized for {nu}{sub e} detection, with a fiducial mass of the order os 20 kton and exposed to neutrino and antineutrino beams. In a five year run its sensitivity to the {nu}{sub {mu}} {yields} {nu}{sub e} oscillations will be at least a factor of ten beyond the current ...
Date: July 30, 2003
Creator: Ayres, D.; Goodman, M.; Guarino, V.; Joffe-Minnor, T.; Reyna, D.; Talaga, R. et al.
Partner: UNT Libraries Government Documents Department

High energy photon-neutrino interactions

Description: A general decomposition of the amplitudes for the 2 {r_arrow} 2 processes {gamma}{nu} {r_arrow} {gamma}{nu} and {gamma}{gamma} {r_arrow} {nu}{bar {nu}} is obtained using gauge invariance and Bose symmetry. The restrictions implied by this decomposition are investigated for the reaction {gamma}{gamma} {r_arrow} {nu}{bar {nu}} by computing the one-loop helicity amplitudes in the standard model. In the center of mass, where {radical}s = 2{omega}, the cross section grows roughly as {omega}{sup 6} up to the threshold for W-boson production, {radical}s = 2m{sub W}. Astrophysical implications of very high energy photon-neutrino interactions are discussed.
Date: July 14, 1998
Creator: Abbasabadi, A.; Devoto, A.; Dicus, D.A. & Repko, W.W.
Partner: UNT Libraries Government Documents Department

Neutrino Physics at Fermilab

Description: The Liquid Scintillator Neutrino Detector (LSND), located at the LANSCE (formerly LAMPF) linear accelerator at Los Alamos National Laboratory, has seen evidence for the oscillation of neutrinos, and hence neutrino mass. That discovery was the impetus for this LDRD project, begun in 1996. The goal of this project was to define the appropriate technologies to use in a follow up experiment and to set in place the requirements for such an experiment.
Date: July 9, 1999
Creator: Federspiel, F.; Garvey, G.; Louis, W.C.; Mills, G.B.; Tayloe, R.; Sandberg, V. et al.
Partner: UNT Libraries Government Documents Department

Discovery of the B{sub C} meson

Description: We report on the first observation of the bottom-charm mesons B{sub c} through the decay mode B{sub c}{sup {+-}} {yields} J/{psi}l{sup {+-}}{nu} in 1.8 TeV p{anti p} collisions using the CDF detector at the Fermilab Tevatron. A fit of background and signal contributions to the observed J/{psi}l mass distribution yielded 20.4{sup +6.2}{sub -5.5} events from B{sub c} mesons. A fit to the same distribution with background alone was rejected at the level of 4.8 standard deviations. We measured the B{sub c}{sup +} mass to be 6.40{+-}0.39{+-}0.13 GeV/c{sup 2} and the B{sub c}{sup +} lifetime to be 0.46{sup 0.18}{sub -0.16}(stat.){+-}0.03(syst.) ps. The measured production cross section times branching ratio for B{sub c}{sup +} {yields} J/{psi}l{sup +}{nu} relative to that for B{sup +} {yields} J/{psi}K{sup +} is 0.132{sup 0.041}{sub -0.037}(stat.){+-}0.031(syst.){sup +0.032}{sub -0.020}(lifetime).
Date: July 1, 1998
Creator: Singh, P.P
Partner: UNT Libraries Government Documents Department

Future prospects of K{sub L} {r_arrow} {pi}{sup 0}{nu}anti-{nu} experiment at Fermilab

Description: The authors reviewed the current status of a proposed KAMI (Kaon at Main Injector) experiment at Fermilab to measure the direct CP-violating K{sub L} {r_arrow} {pi}{sup 0}{nu}anti-{nu} decay. Good progress and encouraging results have been made in the past two years for measuring the required photon veto inefficiencies for both CsI and lead-scintillator detectors in a test beam at INS-KEK Japan. New beam test with 150 GeV Main Injector protons has also been scheduled in January 2000 at Fermilab using the existing KTeV detector with two new beam calorimeters. Prospects of a feasible KAMI experiment in the future is discussed here.
Date: July 5, 2000
Creator: Hsiung, Yee B.
Partner: UNT Libraries Government Documents Department

Neutrino Factory and Muon Collider Collaboration R and D Program

Description: The Neutrino Factory and Muon Collider Collaboration (MC) comprises some 140 scientists and engineers located at U.S. National Laboratories and Universities, and at a number of non-U.S. research institutions. In the past year, the MC R and D program has shifted its focus mainly toward the design issues related to the development of a Neutrino Factory based on a muon storage ring. In this paper the status of the various R and D activities is described, and future plans are outlined.
Date: July 1, 2000
Creator: Zisman, M.S.
Partner: UNT Libraries Government Documents Department

Instrumentation for the muon based neutrino source.

Description: There are a number of novel instrumentation issues relating to the generation cooling and acceleration of high power muon beams. Specific issues are monitoring the cooling water in the magnet nearest the target to minimize corrosion, monitoring the behavior of the target after the impact of the beam, and following the beam through the cooling accelerator chain. The muon cooling system also produces a number of unique issues such as making beam profile measurements in the presence of large backgrounds, measuring these backgrounds, losses, and the angular momentum of the beam. We describe the techniques we intend to use, and some of the constraints involved in their implementation.
Date: July 17, 2001
Creator: Norem, J.; Wang, C.-X. & Solomey, N.
Partner: UNT Libraries Government Documents Department

Double field flip cooling channel for the neutrino factory

Description: A 220 m long ionization cooling system consisting of three solenoids with two field-flip sections, is proposed as a cooling channel for the neutrino factory. The reduction of transverse emittance is achieved using 87 liquid hydrogen absorbers (30-40 cm long), and 87 (2 m long) 200 MHz linacs. The first flip is performed at relatively small magnetic field, B = 3 T, to keep the longitudinal motion under control. The field is then increased adiabatically up to 7 T and a second field flip performed. The cooler was studied and simulated in detail. Preceded by a 16 GeV proton driver, a carbon target, a mini-cooler and a buncher, the system provides about 0.082 muons per incident proton.
Date: July 3, 2001
Creator: al., Valeri Balbekov et
Partner: UNT Libraries Government Documents Department

High energy physics

Description: This proposal is for the continuation of the High Energy Physics Program at the University of California, Riverside. In 1990, we will concentrate on analysis of LEP data from the OPAL detector. We expect to record 10{sup 5} Z`s by the end of 1989 and 10{sup 6} in 1990. This data will be used to measure the number of quark-lepton families in the universe. In the second half of 1990 we will also be occupied with the installation of the D-Zero detector in the Tevatron Collider and the preparation of software for the 1991 run. A new initiative made possible by generous university support is a laboratory for detector development at UCR. The focus will be on silicon strip tracking detectors both for the D-Zero upgrade and for SSC physics. The theory program will pursue further various mass-generating radiative mechanisms for understanding small quark and lepton masses as well as some novel phenomenological aspects of supersymmetry.
Date: July 1, 1997
Creator: Kernan, A.; Shen, B.C. & Ma, E.
Partner: UNT Libraries Government Documents Department

Update of the major results from the GALLEX Cr-neutrino source experiment

Description: This report provides an update about the major results of the GALLEX Cr-neutrino source experiment since November 8, 1994 and reports results of individual measurements of source activity. New data does not change the main conclusion from the November 8, 1994 data: Unknown systematical errors in GALLEX can at the most be of order 10%. 3 refs., 1 fig., 2 tabs.
Date: July 1, 1995
Creator: Collaboration, GALLEX
Partner: UNT Libraries Government Documents Department

Searches for new gauge bosons using the D0 detector

Description: We present the results of searches for additional gauge bosons beyond the W and Z bosons using the 1992-1993 Tevatron data set collected with the D0 detector. The signatures studied are W{prime} {yields} e{nu}, W{prime} {yields} {tau}{nu} with {tau} {yields} e{nu}{bar {nu}}, assuming stable neutrinos; W{sub R} {yields} e + X and W{sub R} {yields} eejj, assuming massive neutrinos; and Z{prime} {yields} ee. Lower limits on the W{prime} mass and Z{prime} mass at the 95% confidence level, and the mass exclusion contour in the W{sub R} mass vs. neutrino mass plane are presented.
Date: July 1, 1995
Creator: Abachi, S.; Abbott, B. & Abolins, M.
Partner: UNT Libraries Government Documents Department

Final research report [Task A: Theory of elementary particles]

Description: This is a summary of some of the work carried out in electroweak physics by the author in collaboration with postdoctoral fellows and students at Oregon, and other colleagues around the world. The past five years have been extraordinarily productive with over thirty refereed publications and over ten presentations in major conferences. The impact of the work on the field has been very significant, especially that related to B physics. In most cases the work is either inspired by experiments or has important consequences for future experiments. The work completed covers a broad spectrum of topics, and can be divided roughly into the following four categories: (1) rare B decays and methods of measuring CP violation at B factories; (2) models of CP violation and their consequences; (3) neutrino properties; and (4) grand unification and its low energy consequences.
Date: July 1, 1996
Creator: Deshpande, N.G.
Partner: UNT Libraries Government Documents Department

Results of the LSND search for {ovr {nu}}{sub {mu}} {yields} {ovr {nu}}{sub e} oscillations

Description: A search for {ovr {nu}}{sub {mu}}{yields}{ovr {nu}}{sub e} oscillations has been conducted at the Los Alamos Meson Physics Facility by using {ovr {nu}}{sub {mu}} from {mu}{sup +} decay at rest. The {ovr {nu}}{sub e} are detected via the reaction {ovr {nu}}{sub e}p {yields} e{sup +} n , correlated with a {gamma} from np {yields} d{gamma} (2.2 MeV). The use of tight cuts to identify e{sup +} events with correlated {gamma} rays yields 22 events with e{sup +} energy between 36 and 60 MeV and only 4.6 {plus_minus} 0.6 background events. The probability that this observation can be explained by statistical fluctuation is less than 10{sup -7}. Assuming these events are due to oscillations, a likelihood fit to all the e{sup +} events between 20 and 60 MeV has been performed to extract the oscillation parameters sin{sup 2} 2{theta} and {Delta}m{sup 2}. The favored region resulting from this fit is shown.
Date: July 1, 1996
Creator: Federspiel, F.J.
Partner: UNT Libraries Government Documents Department

Neutrino properties and fundamental symmetries

Description: This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). There are two components to this work. The first is a development of a new detection scheme for neutrinos. The observed deficit of neutrinos from the Sun may be due to either a lack of understanding of physical processes in the Sun or may be due to neutrinos oscillating from one type to another during their transit from the Sun to the Earth. The Sudbury Neutrino Observatory (SNO) is designed to use a water Cerenkov detector employing one thousand tonnes of heavy water to resolve this question. The ability to distinguish muon and tau neutrinos from electron neutrinos is crucial in order to carry out a model-independent test of neutrino oscillations. We describe a developmental exploration of a novel technique to do this using {sup 3}He proportional counters. Such a method offers considerable advantages over the initially proposed method of using Cerenkov light from capture on NaCl in the SNO. The second component of this work is an exploration of optimal detector geometry for a time-reversal invariance experiment. The question of why time moves only in the forward direction is one of the most puzzling problems in modern physics. We know from particle physics measurements of the decay of kaons that there is a charge-parity symmetry that is violated in nature, implying time-reversal invariance violation. Yet, we do not understand the origin of the violation of this symmetry. To promote such an understanding, we are developing concepts and prototype apparatus for a new, highly sensitive technique to search for time-reversal-invariance violation in the beta decay of the free neutron. The optimized detector geometry is seven times more sensitive than that in previous experiments. 15 refs.
Date: July 1, 1996
Creator: Bowles, T.J.
Partner: UNT Libraries Government Documents Department

Solar Neutrino Physics

Description: With its heavy water target, the Sudbury Neutrino Observatory (SNO) offers the unique opportunity to measure both the 8B flux of electron neutrinos from the Sun and, independently, the flux of all active neutrino species reaching the Earth. A model-independent test of the hypothesis that neutrino oscillations are responsible for the observed solar neutrino deficit can be made by comparing the charged-current (CC) and neutral-current (NC) rates. This LDRD proposal supported the research and development necessary for an assessment of backgrounds and performance of the SNO detector and the ability to extract the NC/CC-Ratio. Particular emphasis is put upon the criteria for deployment and signal extraction from a discrete NC detector array based upon ultra-low background 3He proportional counters.
Date: July 15, 1999
Creator: Bowles, T.J.; Brice, S.J.; Esch, E.-I.; Fowler, M.M.; Goldschmidt, A.; Hime, A. et al.
Partner: UNT Libraries Government Documents Department

Project: Collaborative Research Between Oklahoma State University and Fermilab

Description: Several scientific projects were completed in the area of Theoretical High Energy Physics (Elementary Particles and Fields). The results obtained were published in refereed international journals and presented in several national and international conferences by the project personnel. A brief summary of these four completed projects and the results obtained are given: (1) Collider Physics and Extra Dimensions; (2) Unification and Extra Dimensions; (3) Supersymmetry, Anomalous U(1) Symmetry and Lepton Flavor Violation; and (4) Neutrino Masses and Mixings.
Date: July 29, 2004
Partner: UNT Libraries Government Documents Department

Beam manipulation and compression using broadband rf systems in the Fermilab Main Injector and Recycler

Description: A novel method for beam manipulation, compression, and stacking using a broad band RF system in circular accelerators is described. The method uses a series of linear voltage ramps in combination with moving barrier pulses to azimuthally compress, expand, or cog the beam. Beam manipulations can be accomplished rapidly and, in principle, without emittance growth. The general principle of the method is discussed using beam dynamics simulations. Beam experiments in the Fermilab Recycler Ring convincingly validate the concept. Preliminary experiments in the Fermilab Main Injector to investigate its potential for merging two ''booster batches'' to produce high intensity proton beams for neutrino and antiproton production are described.
Date: July 9, 2004
Creator: al., G William Foster et
Partner: UNT Libraries Government Documents Department

Phase I Rinal Report: Ultra-Low Background Alpha Activity Counter

Description: In certain important physics experiments that search for rare-events, such as neutrino or double beta decay detections, it is critical to minimize the number of background events that arise from alpha particle emitted by the natural radioactivity in the materials used to construct the experiment. Similarly, the natural radioactivity in materials used to connect and package silicon microcircuits must also be minimized in order to eliminate ''soft errors'' caused by alpha particles depositing charges within the microcircuits and thereby changing their logic states. For these, and related reasons in the areas of environmental cleanup and nuclear materials tracking, there is a need that is important from commercial, scientific, and national security perspectives to develop an ultra-low background alpha counter that would be capable of measuring materials' alpha particle emissivity at rates well below 0.00001 alpha/cm{sup 2}/hour. This rate, which corresponds to 24 alpha particles per square meter per day, is essentially impossible to achieve with existing commercial instruments because the natural radioactivity of the materials used to construct even the best of these counters produces background rates at the 0.005 alpha/cm{sup 2}/hr level. Our company (XIA) had previously developed an instrument that uses electronic background suppression to operate at the 0.0005 0.005 alpha/cm{sup 2}/hr level. This patented technology sets up an electric field between a large planar sample and a large planar anode, and fills the gap with pure Nitrogen. An alpha particle entering the chamber ionizes the Nitrogen, producing a ''track'' of electrons, which drift to the anode in the electric field. Tracks close to the anode take less than 10 microseconds (us) to be collected, giving a preamplifier signal with a 10 us risetime. Tracks from the sample have to drift across the full anode-sample gap and produce a 35 us risetime signal. By analyzing the preamplifier signals ...
Date: July 22, 2005
Creator: Warburton, W.K.
Partner: UNT Libraries Government Documents Department

Search for fourth generation neutral heavy leptons

Description: A search for fourth generation neutral heavy leptons ({nu}{sub 4}) in W decays was carried out the D0 detector at the Fermilab Tevatron at {radical}{bar s} = 1.8 TeV. The {nu}{sub 4} is assumed to be produced via mixing with the first generation neutrino only. We looked for a three electron final state event topology. The data used in this analysis represent 12.2 pb{sup {minus}1} taken during the 1992--1993 run. No candidates were found. We set a preliminary limit beyond the LEP limit for the considered mixing case on the {vert_bar}U{sub e4}{vert_bar}{sup 2} {minus} m{sub {nu}4} plane.
Date: July 1, 1995
Creator: Abachi, S.; Abbott, B.; Abolins, M. & Collaboration, D0
Partner: UNT Libraries Government Documents Department

CPT Tests: Kaon vs neutrinos

Description: CPT violation has an impressive limit in the neutral kaon system |m(K{sup 0})-m({bar K}{sup 0})| < 10{sup -18} m{sub K} = 0.50 x 10{sup -18} GeV. However, if viewed as a constraint on the mass-squared, the bound appears weak, |m{sup 2}(K{sup 0})-m{sup 2}({bar K}{sup 0})| < 0.25 eV{sup 2}. the authors point out that neutrino oscillation offers better limits on CPT violation in this case. The comparison of solar and rector neutrino results puts the best limit on CPT violation by far, |{Delta}m{sub {nu}}{sup 2}-{Delta}m{sub {rho}}{sup 2}| < 1.3 x 10{sup -3} eV{sup 2} (90% CL).
Date: July 9, 2003
Creator: Murayama, Hitoshi
Partner: UNT Libraries Government Documents Department

Measurement of theta{sub 13} with reactor neutrinos

Description: Recent experimental results have provided unambiguous evidence that neutrinos have a small but finite mass and mix from one type into another. The phenomenon of neutrino mixing is characterized by the coupling between the neutrino flavor (nu{sub e,mu,tau}) and mass eigenstates (nu{sub 1,2,3}) and the associated mixing angles. Previous neutrino oscillation experiments have determined two of the three mixing angles in the neutrino mixing matrix, U{sub MNSP}. Using multiple neutrino detectors placed at different distances from a nuclear power plant, a future reactor neutrino experiment has the potential to discover and measure the coupling of the electron neutrino flavor to the third mass eigenstate, U{sub e3}, the last undetermined element of the neutrino mixing matrix.
Date: July 13, 2004
Creator: Heeger, Karsten M.; Freedman, Stuart J.; Kadel, Richard W. & Luk, Kam-Biu
Partner: UNT Libraries Government Documents Department


Description: During the second stage of a future neutrino factory unprecedented numbers of bunched muons will become available. The cooled medium-energy muon beam could be used for a high sensitivity search for an electric dipole moment (EDM) of the muon with a sensitivity better than 10{sup -24}e {center_dot} cm. This will make the sensitivity of the EDM experiment to non-standard physics competitive and in many models more sensitive than the present limits on edms of the electron and nucleons. The experimental design exploits the strong motional electric field sensed by relativistic particles in a magnetic storage ring.
Date: July 1, 2002
Partner: UNT Libraries Government Documents Department