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High energy physics studies. Progress report for Task D

Description: The major research activity of Task D has been collaboration in experiments E791 and E871 at Brookhaven National Laboratory. During the past year, the collaboration has published results of the second major run, nearly completed analysis of the final data from the experiment and reported some of these results in conferences. The authors now have a substantially better understanding of the potential backgrounds and systematic uncertainties in the experiment. This understanding is important for both the results to be derived from the present data and for future experiments. In addition, they have conducted extensive tests for the new experiment at Brookhaven. Their goal is to improve the sensitivity to rare decay modes of kaons by a factor of 20 over the final E791 result. In the coming year the authors will finish the final analysis of all data from the experiment, including a consistent reanalysis of all data and preparation of a Phys. Rev. D article describing the measurement. Assuming approval of E871 by BNL, they will finalize detailed design of the experiment and begin prototype testing and construction. In addition to the ongoing efforts on E791 and E871 at BNL, they have begun looking at the possibility of mounting a substantially improved experiment to be performed at the proposed Main Injector at Fermilab. This effort would be part of a Main Injector Kaon Facility. In this contract renewal request, they will review the current status of lepton flavor violation in K decays, summarize the status of the experiment, report in some detail on a number of the specific projects in which personnel supported by this contract have been involved, discuss the possibilities for future directions of the experiment, and list specific requests to the funding agency.
Date: August 1, 1991
Creator: Molzon, W.R.
Partner: UNT Libraries Government Documents Department

A precision measurement of the branching ratio K{sup +} {r_arrow} {pi}{sup +}{pi}{sup 0}/K{sup +} {r_arrow} {mu}{sup +}{nu}{sub {mu}}

Description: A measurement of the branching ratio K{sup +} {r_arrow} {pi}{sup +}{pi}{sup 0}/K{sup +} {r_arrow} {mu}{sup +}{nu}{sub {mu}} was made using stopped kaons from p{anti p} annihilations at rest and a magnetic spectrometer to measure the momenta of the charged decay product to the 1% to 1.5% level. The determination is based on 45,500 events passing final data cuts. The resulting ratio is .3329 {+-} .0047 (statistical) {+-} .0010 (systematic).
Date: August 1, 1991
Creator: Usher, T.; Fero, M.; Gee, M.; Graf, N.A.; Mandelkern, M.; Shultz, D. et al.
Partner: UNT Libraries Government Documents Department

1991 Technical progress report of the University of South Carolina`s High Energy Physics Group, February 1990--July 1991

Description: The high energy physics group at the University of South Carolina includes five teaching faculty members, one research faculty member, and five graduate students. Profs. Childers, Darden, and Wilson devote most of their research effort to Fermilab experiment E789, which is designed to observe charmless two-body decays of b-flavored mesons and baryons. Prof. Wilson works on Fermilab experiment E687 which studies charm physics in the wide-band photon beam. Profs. Rosenfeld and Wang participate in the AMY collaboration, which studies electron-positron interactions using the TRISTAN collider at KEK. Prof. Rosenfeld and one student collaborate with personnel from KEK and INS, Tokyo, on an experiment to detect a 17 keV neutrino in the {beta}-decay spectrum of {sup 63}Ni. Members of the group also participate in Fermilab Proposal P803 which will search for the oscillation of muon neutrino to tau neutrino with sensitivity better than a factor of 40 than previously achieved and in Superconducting Super Collider activities which include the development of an imaging preradiator. A brief discussion is given on progress made for each program.
Date: December 31, 1991
Partner: UNT Libraries Government Documents Department

Non-accelerator particle physics

Description: The goals of this research are the experimental testing of fundamental theories of physics such as grand unification and the exploration of cosmic phenomena through the techniques of particle physics. We are working on the MACRO experiment, which employs a large area underground detector to search for grand unification magnetic monopoles and dark matter candidates and to study cosmic ray muons as well as low and high energy neutrinos: the {nu}IMB project, which seeks to refurbish and upgrade the IMB water Cerenkov detector to perform an improved proton decay search together with a long baseline reactor neutrino oscillation experiment using a kiloton liquid scintillator (the Perry experiment); and development of technology for improved liquid scintillators and for very low background materials in support of the MACRO and Perry experiments and for new solar neutrino experiments. 21 refs., 19 figs., 6 tabs.
Date: September 1, 1991
Creator: Steinberg, R.I. & Lane, C.E.
Partner: UNT Libraries Government Documents Department

Is there a P-wave bound state of W sub L W sub L On the dynamical generation of a. rho. meson in the. sigma. model

Description: We investigate the possibility that the Higgs lagrangian predicts the existence of a P-wave W{sub L}W{sub L} resonance. This problem is equivalent to studying the formation of the {rho} meson by the dynamics contained in the {sigma} model. Using the Pade approximation, Basdevant and Lee had claimed that {rho} is generated dynamically. We show that their result, while computationally correct, is not significant, because of the position of the Landau ghost. For the same reason, a W{sub L}W{sub L} P-wave resonance below 2 TeV is not expected, unless the standard model is violated. 10 refs., 8 figs.
Date: October 1, 1991
Creator: Atkinson, D. (Fermi National Accelerator Lab., Batavia, IL (United States) Institute for Theoretical Physics, Groningen, The Netherlands (NL)); Harada, M. (Nagoya Univ. (Japan). Dept. of Physics) & Sanda, A.I. (Superconducting Super Collider Lab., Dallas, TX (United States) Rockefeller Univ., New York, NY (United States). Dept. of Physics)
Partner: UNT Libraries Government Documents Department

The search for the H dibaryon with the BNL 2. 0 GeV/c kaon beam

Description: The status is given for two experiments being carried out to search for evidence of the H dibaryon. BNL experiments E813 and E836 will use the new 2 GeV/c kaon beam line. The former has recently begun data taking. They cover complementary regions of mass-sensitivity and promise to provide sensitive tests of the existence of the H. 12 refs.
Date: January 1, 1991
Creator: Quinn, B.P.
Partner: UNT Libraries Government Documents Department

Neutron induced pion production on C, Al, Cu, and W at neutron energies of 200--600 MeV

Description: Inclusive double differential neutron induced {pi}{sup +} and {pi}{sup {minus}} production cross sections were measured for four separate targets: C, Al, Cu and W. The neutron energy range was 200--600 MeV and the pion angular range was 25{degrees}--125{degrees}. The charge, scattering angle and energy of the pions were measured using a magnetic spectrometer. The measurements are compared with intranuclear cascade (INC) calculations and a previous experiment that measured the sum of the {pi}{sup +} and {pi}{sup {minus}} cross sections. Our data agree with the measured data, but the INC calculations give only moderate agreement with the double differential cross sections as well as with angular distributions and total cross sections as a function of neutron energy. The ratio of {pi}{sup {minus}}:{pi}{sup +} was found to increase rapidly with decreasing neutron energy and the pion production was found to increase approximately as A{sup 2/3} for the different targets. 31 refs., 55 figs., 6 tabs.
Date: October 1, 1991
Creator: Brooks, M.L.
Partner: UNT Libraries Government Documents Department

Update to the RHIC Letter of Intent for an experiment on particle and jet production at midrapidity

Description: This document is an Update to the Letter of Intent (LOI) submitted by this collaboration in September 1990 proposing a large acceptance solenoidal tracking experiment. Since that time the collaboration has chosen the name STAR, representing Solenoidal Tracker At RHIC. The physics interests of the STAR collaboration and the goals of the experiment are described in the original LOI. Since submission of the LOI, several changes have been made in the design of the experiment motivated by the desire to expand pseudorapidity coverage for complete event characterization and by the necessity to achieve cost reduction. The major changes are: Expansion of pseudorapidity coverage to {vert bar}{eta}{vert bar} < 4.5 by the addition of tracking chambers external to the magnet; reduction in the number of time-of-flight channels from 100K to 10K; staging implementation of hadronic calorimetry while using tracking and electromagnetic calorimetry to extract parton physics in the initial configuration; reduction in the cost per channel of Time Projection Chamber (TPC) electronics through continued TPC electronics R D supported from RHIC funds; and a change in the Silicon Vertex Tracker (SVT) technique to the use of silicon drift chambers. These changes and the status of ongoing R D programs to optimize the design and performance of the STAR experiment will be presented. In terms of detector performance it will be demonstrated that the space charge loading of the TPC is negligible and that the STAR experiment can operate at the highest RHIC luminosities. A summary of the detector systems is presented in this paper.
Date: July 1, 1991
Partner: UNT Libraries Government Documents Department

Current status of the E(1420)/. iota. (1440) and future prospects of the g sub T decaying into. phi. phi

Description: A survey is given of the current status of the f{sub 1}(1420)/E and the {eta}(1440)/{iota} in the channels of K {bar K}{pi} and {eta}{pi}{pi}. There is now strong evidence that the {eta}(1440)/{iota} is split into two J{sup PC} = o{sup {minus}+} states in the 1.4--1.5 GeV range with the lower-mass state coupling mostly to a{sub 0}(980){pi} whereas the upper-mass state couples mainly to K*(890){bar K}. Both of them cannot be quarkonia. It appears very likely that the f{sub 1}(1420)/E is an S-wave K*(890){bar K} molecule with a strong overlap with the a{sub 0}(980)/{delta}. It is thought that one or more of the J{sup PC} = 1{sup ++} f{sub 2}(2010)/g{sub r}, F{sub 2}(2300)/g{sub T}{prime} and f{sub 2}(2340)/g{sub f}{double prime} states decaying into {phi}{phi} may be the tensor glueball. The future prospects at BNL and elsewhere for further experimental work on these on other exotic states coupling to {phi}{phi} are discussed.
Date: December 1, 1991
Creator: Chung, S.U.
Partner: UNT Libraries Government Documents Department

Proposal for a CLEO precision vertex detector

Description: Fermilab experiment E691 and CERN experiment NA32 have demonstrated the enormous power of precision vertexing for studying heavy quark physics. Nearly all collider experiments now have or are installing precision vertex detectors. This is a proposal for a precision vertex detector for CLEO, which will be the pre-eminent heavy quark experiment for at least the next 5 years. The purpose of a precision vertex detector for CLEO is to enhance the capabilities for isolating B, charm, and tau decays and to make it possible to measure the decay time. The precision vertex detector will also significantly improve strange particle identification and help with the tracking. The installation and use of this detector at CLEO is an important step in developing a vertex detector for an asymmetric B factory and therefore in observing CP violation in B decays. The CLEO environment imposes a number of unique conditions and challenges. The machine will be operating near the {gamma} (4S) in energy. This means that B's are produced with a very small velocity and travel a distance about {1/2} that of the expected vertex position resolution. As a consequence B decay time information will not be useful for most physics. On the other hand, the charm products of B decays have a higher velocity. For the long lived D{sup +} in particular, vertex information can be used to isolate the charm particle on an event-by-event basis. This helps significantly in reconstructing B's. The vertex resolution for D's from B's is limited by multiple Coulomb scattering of the necessarily rather low momentum tracks. As a consequence it is essential to minimize the material, as measured in radiation lengths, in the beam pip and the vertex detector itself. It is also essential to build the beam pipe and detector with the smallest possible radius.
Date: January 1, 1991
Partner: UNT Libraries Government Documents Department

Search for the H-dibaryon at the Brookhaven 2 GeV/c kaon beam line

Description: In this talk I will summarize the motivation for H-dibaryon searches and describe efforts at Brookhaven to find this particle. The most recently run experiment, using a new 2 GeV/c kaon beam line, has looked for the H in the at-rest formation reaction ({Xi}{sup {minus}} + d){sub atom} {r arrow} H + n, where the monoenergetic neutron was detected. This experiment is sensitive to an H in the range near the {Lambda}{Lambda} mass, a region largely unconstrained by other measurements. Data analysis is in progress, so no results are available yet. A second search technique using a {sup 3}He target is also described.
Date: January 1, 1991
Creator: Schumacher, R.A.
Partner: UNT Libraries Government Documents Department

A proposed search for dark-matter axions in the 0. 6--16. mu. eV range

Description: A proposed experiment is described to search for dark-matter axions in the mass range 0.6--16 {mu}eV. The method is based on the Primakoff conversion of axions into monochromatic microwave photons inside a tunable microwave cavity in a large volume high field magnet. This proposal capitalized on the availability of two Axicell magnets from the MFTF-B fusion machine at LLNL. Assuming a local dark-matter density in axions of {rho}{sub a}= 0.3 GeV/cm{sup 3}, the axion would be found or ruled out at the 97% c.1. in the above mass range in 48 months.
Date: November 1, 1991
Creator: Hagmann, C. (California Univ., Berkeley, CA (United States). Dept. of Physics); Moltz, D.M. (Lawrence Berkeley Lab., CA (United States)); Turner, M.S. (Chicago Univ., IL (United States). Dept. of Physics and Astronomy Fermi National Accelerator Lab., Batavia, IL (United States)); Sikivie, P.; Sullivan, N.S.; Tanner, D.B. (Florida Univ., Gainesville, FL (United States). Dept. of Physics) et al.
Partner: UNT Libraries Government Documents Department

The W boson transverse momentum spectrum in proton-antiproton collisions at radical s = 1. 8 TeV

Description: The Collider Detector at Fermilab (CDF) was used to measure the transverse momentum distribution of W boson produced in proton-antiproton collisions at the Tevatron collider. The W bosons were identified by the decay W {yields} e{nu}. The results are in good agreement with a next-to-leading order calculation. The cross section for W production with P{sub T} > 50 GeV/c is 423 {plus minus} 58 (stat.) {plus minus} 108 (sys.) pb. 58 refs., 53 figs., 16 tabs.
Date: February 1, 1991
Creator: Winer, B.L.
Partner: UNT Libraries Government Documents Department

Hunting and identifying new gauge bosons at the NLC

Description: We examine the ability of the NLC ({radical}{bar s} = 500 GeV) e{sup +}e{sup {minus}} linear collider to discover and identify the origin of new neutral gauge bosons, with masses in excess of the machine's center of mass energy, via deviations from the predictions of the Standard Model for the process e{sup +}e{sup {minus}} {yields} {bar f}f. New gauge bosons with masses in the few TeV regime may be probed at such at collider. 7 refs., 3 figs., 2 tabs.
Date: October 1, 1991
Creator: Hewett, J.L. (Argonne National Lab., IL (United States)) & Rizzo, T.G. (Argonne National Lab., IL (United States) Ames Lab., IA (United States))
Partner: UNT Libraries Government Documents Department

Identifying the origin of new gauge bosons at the SSC and LHC

Description: The ability of an SCD-like detector to identify the origin of a new neutral gauge boson Z{sub 2}, once it has been discovered at the SSC and/or LHC, is examined. 9 refs., 3 figs.
Date: August 1, 1991
Creator: Hewett, J.L. (Argonne National Lab., IL (United States)) & Rizzo, T.G. (Argonne National Lab., IL (United States) Ames Lab., IA (United States))
Partner: UNT Libraries Government Documents Department

Search for the H particle: Its production and weak decay

Description: Jaffe has suggested that a six-quark state with the flavor content of two-lambda hyperons with all spins coupled to zero, the H particle, may be bound against strong decay. This particle has become the object of extensive discussion in the literature and of several experimental searches. We report here the present status of an investigation of the reaction: ({Xi}{minus},d){sub atom}{yields} H + n in experiment E-813 at the BNL-AGS and describe plans for future running in 1992.
Date: January 1, 1991
Creator: Barnes, P.D.
Partner: UNT Libraries Government Documents Department

Search for top quark at Fermilab Collider

Description: The status of a search for the top quark with Collider Detector at Fermilab (CDF), based on a data sample recorded during the 1988--1989 run is presented. The plans for the next Fermilab Collider run in 1992--1993 and the prospects of discovering the top quark are discussed. 19 refs., 4 figs., 2 tabs.
Date: October 1, 1991
Creator: Sliwa, K. (Tufts Univ., Medford, MA (United States). Dept. of Physics)
Partner: UNT Libraries Government Documents Department

The search for top at CDF

Description: We present results on the search for the top quark in {bar p}p collisions at {radical}s = 1.8 TeV. The data sample collected during the 1988--89 run with the Collider Detector at Fermilab (CDF) includes more than 4 pb{sup {minus}1}. We report here on an extension of previously published searches for the top quark in electron + jets and the dilepton channel electron-muon. The 95% confidence level limit on the top mass is 89 GeV/c{sup 2}.
Date: August 1, 1991
Creator: Liss, T.M. (Illinois Univ., Urbana, IL (United States). Loomis Lab. of Physics)
Partner: UNT Libraries Government Documents Department

Direct production of high p sub t leptons and search for additional heavy bosons at 1. 8 TeV

Description: We have studied the production of high p{sub t} electrons and muons and searched for additional heavy charged (W{prime}) and neutral (Z{prime}) vector bosons. We find no evidence for such bosons and set limits of M{sub w}{prime} > 520 GeV and M{sub Z}{prime} > 412 GeV (95% confidence level) assuming Standard Model couplings. The production of high mass electron and muon pairs is consistent with the Standard Model prediction for the Drell-Yan production mechanism. Lower limits of 2.2 TeV and 1.6 TeV (95% confidence level) are set on electron-quark and muon-quark compositeness scale parameters {Lambda}{sub LL}{sup {minus}} associated with an effective contact interaction.
Date: October 1, 1991
Creator: Gold, M. (Lawrence Berkeley Lab., CA (United States))
Partner: UNT Libraries Government Documents Department

Top search at CDF

Description: We review top quark searches carried out at CDF with data collected during the 1988--1989 Collider Run. The latest analyses give a lower limit on the top quark mass of 91 GeV/c{sup 2} at the 95% confidence level, assuming Standard Model decays. 8 refs., 6 figs., 1 tab.
Date: October 1, 1991
Creator: Contreras, M. (Chicago Univ., IL (United States))
Partner: UNT Libraries Government Documents Department

Search for W prime and Z prime at CDF

Description: We have searched for heavy charged and neutral vector bosons via the decays W{prime} {yields} ev, W{prime} {yields} {mu}v, Z{prime} {yields} {mu}{mu} in p{bar p} collisions at {radical}s = 1.8 TeV, using data taken with the collider Detector at Fermilab. The nonobservation of these processes leads to a lower limit (95% confidence level) of 520 GeV/c{sup 2} on the mass of the W{prime} and of 412 GeV/C{sup 2} on the mass of the Z{prime}, assuming standard model coupling to fermions. 12 refs., 6 figs., 1 tab.
Date: September 1, 1991
Creator: Fuess, T.
Partner: UNT Libraries Government Documents Department

Physics at e sup + e sup minus factories

Description: Feasible designs are well advanced for high-luminosity e{sup +}e{sup {minus}} storage rings which produce B{sup 0}{bar B}{sup 0} pairs either at rest or, in what appears to be a more promising option, boosted in the detector frame. Facilities which could provide samples of 30--100 fb{sup {minus}1} per year on the {Upsilon}(4S) will be proposed in early 1991. Here we examine the principal physics goal of such B Factories, namely CP violation in the b system. Methods in a variety of channels, estimated event samples, and detector requirements are all considered. We conclude that the physics argument for an e{sup +}e{sup {minus}} B Factory is well documented, and compelling. 50 refs., 22 figs., 10 tabs.
Date: February 1, 1991
Creator: Lueth, V. (Stanford Linear Accelerator Center, Menlo Park, CA (USA)) & MacFarlane, D.B. (McGill Univ., Montreal, PQ (Canada))
Partner: UNT Libraries Government Documents Department

Particle identification at an asymmetric B Factory

Description: Particle identification systems are an important component of any detector at a high-luminosity, asymmetric B Factory. In particular, excellent hadron identification is required to probe CP violation in B{sup 0} decays to CP eigenstates. The particle identification systems discussed below also provide help in separating leptons from hadrons at low momenta. We begin this chapter with a discussion of the physics motivation for providing particle identification, the inherent limitations due to interactions and decays in flight, and the requirements for hermiticity and angular coverage. A special feature of an asymmetric B Factory is the resulting asymmetry in the momentum distribution as a function of polar angle; this will also be quantified and discussed. In the next section the three primary candidates, time-of-flight (TOF), energy loss (dE/dx), and Cerenkov counters, both ring-imaging and threshold, will be briefly described and evaluated. Following this, one of the candidates, a long-drift Cerenkov ring-imaging device, is described in detail to provide a reference design. Design considerations for a fast RICH are then described. A detailed discussion of aerogel threshold counter designs and associated R D conclude the chapter. 56 refs., 64 figs., 13 tabs.
Date: September 1, 1991
Creator: Coyle, P.; Eigen, G.; Hitlin, D.; Oddone, P.; Ratcliff, B.; Roe, N. et al.
Partner: UNT Libraries Government Documents Department