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The Capabilities of the upgraded MIPP experiment with respect to Hypernuclear physics

Description: We describe the state of analysis of the MIPP experiment, its plans to upgrade the experiment and the impact such an upgraded experiment will have on hypernuclear physics. The upgraded MIPP experiment is designed to measure the properties of strong interaction spectra form beams {pi}{sup {+-}}, K{sup {+-}}, and p{sup {+-}}, for momenta ranging from 1 GeV/c to 120 GeV/c. The layout of the apparatus in the data taken so far can be seen in Figure 1. The centerpiece of the experiment is the time projection chamber, which is followed by the time of flight counter, a multi-cell Cerenkov detector and the RICH detector. The TPC can identify charged particles with momenta less than 1 GeV/c using dE/dx, the time of flight will identify particles below approximately 2 GeV/c, the multi-cell Cerenkov detector is operational from 2.5 GeV/c to 14 GeV/c and the RICH detector can identify particles up to 120 GeVc. Following this is an EM and hadronic calorimeter capable of detecting forward going neutrons and photons. The experiment has been busy analyzing its data taken on various nuclei and beam conditions. The table 2 shows the data taken by MIPP I to date. We have almost complete acceptance in the forward hemisphere in the lab using the TPC. The reconstruction capabilities of the TPC can be seen in Figure 3. The particle identification capabilities of the TPC can be seen in Figure 4. The time of flight system provides further measurement of the particles with momenta less than 2 GeV/c. Figure 5 shows the time of flight data where a kaon peak is clearly visible.
Date: January 1, 2012
Creator: Raja, Rajendran
Partner: UNT Libraries Government Documents Department

An improved Neutrino Oscillations Analysis of the MiniBooNE Data

Description: We calculate the exclusion region in the parameter space of {nu}{sub {mu}} {yields} {nu}{sub e} oscillations of the LSND type using a combined fit to the reconstructed energy distributions of neutrino candidate samples from the MiniBooNE data obtained with two different particle identification methods. The two {nu}{sub e} candidate samples are included together with a high statistics sample of {nu}{sub {mu}} events in the definition of a {chi}{sup 2} statistic which includes the correlations between the energy intervals of all three samples and handles the event overlap between the {nu}{sub e} samples. The {nu}{sub {mu}} sample is introduced to constrain the effect of systematic uncertainties. This analysis increases the exclusion limit in the region {Delta}m{sup 2} {approx}< 1eV{sup 2} when compared with the result previously published by the collaboration, which used a different technique.
Date: January 1, 2008
Creator: Aguilar-Arevalo, Alexis Armando & U., /Columbia
Partner: UNT Libraries Government Documents Department

Proposal for Research and Development: Vertexing, Tracking, and Data Acquisition for the Bottom Collider Detector

Description: The authors propose a program of research and development into the detector systems needed for a B-physics experiment at the Fermilab p-{bar p} Collider. The initial emphasis is on the critical issues of vertexting, tracking, and data acquisition in the high-multiplicity, high-rate collider environment. R and D for the particle-identification systems (RICH counters, TRD's, and EM calorimeter) will be covered in a subsequent proposal. To help focus their efforts in a timely manner, they propose the first phase of the R and D should culminate in a system test at the C0 collider intersect during the 1990-1991 run: a small fraction of the eventual vertex detector would be used to demonstrate that secondary-decay vertices can be found at a hadron collider. The proposed budget for the r and D program is $800k in 1989, $1.5M in 1990, and $1.6M in 1991.
Date: January 1, 1989
Creator: Castro, H.; Gomez, B.; Rivera, F.; Sanabria, J.-C.; U., /Los Andes; Yager, P. et al.
Partner: UNT Libraries Government Documents Department

Studies of nuclear reaction at very low energies

Description: The deuteron radiative capture reactions on {sup 2}H, {sup 6}Li and {sup 10}B have been measured between center of mass energies of 20 and 140 keV. Of note is the observation that the gamma ray-to-charged particle branching ratio for the DD reaction appears independent of energy down to a center of mass energy of 20 keV, consistent with some and contrary to other theoretical models. We have investigated the ratio of the reactions D(d,p)T and D(d,n){sup 3}He down to c.m. energies of 3 keV and the ratio of the reactions 6Li(d,p){sup 7}Li and {sup 6}LI(d,{alpha}){sup 4}He down to a c.m. energy of 19 keV. The DD reaction ratio is independent of energy while the (d,p) branch of the D-{sup 6}Li evinces a significant enhancement at the lowest measured energies. We have continued our investigation of charged particle production from deuterium-metal systems at a modest level of activity. Noteworthy in this investigation is the observation of 3 MeV protons from deuteron beam loaded Ti and LiD targets subjected to extreme thermal disequilibria. Significant facility improvements were realized during the most recent contract period. Specifically the downstream magnetic analysis system proposed to eliminate beam induced contaminants has been installed and thoroughly tested. This improvement should allow the D(a,{gamma}){sup 6}Li reaction to be measured in the coming contract period. A scattering chamber required for the measurement of the {sup 7}Li({sup 3}He,p){sup 9}Be reaction has been designed, fabricated and installed on the accelerator. A CAMAC based charged particle identification system has been assembled also for use in our proposed measurement of the {sup 7}Li({sup 3}He, p){sup 9}Be.
Date: January 15, 1992
Creator: Cecil, F.E.
Partner: UNT Libraries Government Documents Department

Gluonia. [Xi-2200 resonances]

Description: The postulated existence of hadrons with no quark content, implied by the non-Abelian nature of quantum chromodynamics, has been the object of much experimental activity. Recent data from radiative psi decay permit a confrontation of available evidence with the most simple-minded criteria for their appearance. In the absence of compellingly positive evidence we give a rating of the relative merits of several possible candidates. 36 references, 17 figures.
Date: January 1, 1985
Creator: Heusch, C.A.
Partner: UNT Libraries Government Documents Department

D0 Project at Fermilab

Description: The D0 Project will explore 2 TeV anti pp collisions at Fermilab using a highly optimized calorimetric detector, to elucidate the new physics coming out of the SppS, and to explore the new higher energy regime. The design and physics potential of the detector system are described.
Date: January 1, 1984
Creator: Marx, M.D.
Partner: UNT Libraries Government Documents Department

Operation of a high-P/sub T/ spectrometer arm at 10/sup 33/ cm/sup -2/ sec/sup -1/ with particle identification

Description: In the Proceedings of the 1978 Isabelle Summer Study a high-pT spectrometer pair is presented as a prototype high-luminosity experiment. We consider here an updated version of this apparatus with the following questions in mind: (1) what rate capabilities are required to cope with L = 10/sup 33/cm/sup -2/sec/sup -1/; (2) what segmentation is needed to deal with the particle densities expected in high pT jets; and (3) is the resulting device within the reach of present technology. The current version of the device and the expected rates are presented, and the rates and segmentation of the components are discussed. The results of calculations related to event pile-up and triggering are presented. The main conclusion, that particle identification appears to be quite feasible at these rates, is discussed in detail. (WHK)
Date: January 1, 1983
Creator: Aronson, S.; Goldberg, M.; Holder, M. & Loh, E.
Partner: UNT Libraries Government Documents Department

Measurement of the response of an SCGl-C scintillation glass array to a 4-14 GeV/c pions

Description: An SCGl-C scintillation glass detector consisting of a 3.5 radiation length SCGl-C active converter followed by scintillation and gas tube hodoscopes and a 4 x 4 array of a 20.5 radiation length SCGl-C counters has been exposed to pions in the 4 to 14 GeV/c momentum range. The response of this detector to pions is compared with the response to electrons of the same momentum in order to distinguish between the two types of particles. Using only longitudinal and tranverse shower development criteria the electrons and pions can be separated such that on average 1.1 x 10/sup -1/ of all pions in the range of 4 to 14 GeV/c would be misidentified as electrons of any energy. If the momentum of the incident particle is known and can be used in the identification technique, this average fraction is reduced to 6.4 x 10/sup -3/ of all pions misidentified as electrons of the same momentum.
Date: January 1, 1984
Creator: Cox, B.; Jenkins, C. M.; Judd, D. J.; Hale, G.; Mazur, P. O.; Murphy, C. T. et al.
Partner: UNT Libraries Government Documents Department

The CEBAF Large Acceptance Spectrometer (CLAS)

Description: The CEBAF Large Acceptance Spectrometer (CLAS) is used to study photo- and electro-induced nuclear and hadronic reactions by providing efficient detection of neutral and charged particles over a good fraction of the full solid angle. A collaboration of about thirty institutions has designed, assembled, and commissioned CLAS in Hall B at the Thomas Jefferson National Accelerator Facility. The CLAS detector is based on a novel six-coil toroidal magnet which provides a largely azimuthal field distribution. Trajectory reconstruction using drift chambers results in a momentum resolution of 0.5% at forward angles. Cerenkov counters, time-of-flight scintillators, and electromagnetic calorimeters provide good particle identification. Fast triggering and high data acquisition rates allow operation at a luminosity of 10{sup 34} nucleon cm {sup -2}s{sup -1}. These capabilities are being used in a broad experimental program to study the structure and interactions of mesons, nucleons, and nuclei using polarized and unpolarized electron and photon beams and targets. This paper is a comprehensive and general description of the design, construction and performance of CLAS.
Date: January 1, 2003
Creator: Mecking, Bernhard & Collaboration, CLAS
Partner: UNT Libraries Government Documents Department

Search for the B{sub c} meson in hadronic Z{sup 0} decays using the OPAL detector at LEP

Description: A search for decays of the B{sub c} meson was performed using data collected from 1990--1995 with the OPAL detector on or near the Z{sup 0} peak at LEP. The decay channels B{sub c}{sup +} {r_arrow} J/{psi}{pi}{sup +}, B{sub c}{sup +} {r_arrow} J/{psi}a{sub 1}{sup +} and B{sub c}{sup +} {r_arrow} J/{psi}{ell}{sup +}{nu} were investigated, where {ell} denotes an electron or a muon. Two candidates are observed in the mode B{sub c}{sup +} {r_arrow} J/{psi}{pi}{sup +}, with an estimated background of (0.63 {+-} 0.20) events. The weighted mean of the masses of the two candidates is (6.32 {+-} 0.06) GeV/c{sup 2}, which is consistent with the predicted mass of the B{sub c} meson. One candidate event is observed in the mode B{sub c}{sup +} {r_arrow} J/{psi}{ell}{sup +}{nu}, with an estimated background of (0.82 {+-} 0.19) events. No candidate events are observed in the B{sub c}{sup +} {r_arrow} J/{psi}a{sub 1}{sup +} decay mode, with an estimated background of (1.10 {+-} 0.22) events. Upper bounds at the 90% confidence level are set on the production rates for these processes.
Date: January 1, 1999
Creator: Herndon, M.F.
Partner: UNT Libraries Government Documents Department

Tau jet signals for supersymmetry at the Tevatron

Description: The authors present a more detailed account of the study (hep-ph/9903238) for the supersymmetry reach of the Tevatron in channels with isolated leptons and identified tau jets. They review the theoretical motivations for expecting such signatures, and describe the relevant parameter space in the minimal supergravity and the minimal gauge-mediated models. With explicit Monte Carlo simulations they then show that for certain parameter ranges, channels with two leptons and one tau jet offer a better reach in Run 2 than the clean trilepton signal. They emphasize that improving on tau ID is an important prerequisite for successful searches in multiple tau jet channels. Finally, they discuss some triggering issues.
Date: January 25, 2000
Creator: Lykken, J.D. & Matchev, K.T.
Partner: UNT Libraries Government Documents Department

The MINOS long-baseline experiment at Fermilab

Description: The MINOS (Main Injector Neutrino Oscillation Search) long-baseline experiment will search for neutrino oscillations by measuring an intense {nu}{sub {mu}} beam at the end of a 730 km flight path. The 10,000 ton MINOS far detector will utilize magnetized steel plates interleaved with track chambers to reconstruct event topologies and to measure the energies of the muons, hadrons and electromagnetic showers produced by neutrino interactions. The experiment is designed to detect {nu}{sub {mu}} {r_arrow} {nu}{sub {tau}} and {nu}{sub {mu}} {r_arrow} {nu}{sub e} oscillations with {Delta}m{sup 2} {ge} 0.001 eV{sup 2} and sin{sup 2} (2{theta}) {ge} 0.01. Any oscillation signal observed can be verified and studied by several independent tests: a near/far rate comparison, the NC/CC event ratio, the CC and NC event energy spectra, and the identification of electrons and {tau} leptons. The neutrino beam can be operated in both wide-band and narrow-band configurations, allowing the detailed study oscillation phenomena. The experiment is scheduled to begin operation in 2001.
Date: January 2, 1997
Creator: Ayres, D.S.
Partner: UNT Libraries Government Documents Department

CP violation and rare decays

Description: After a brief essay on the current state of particle physics and possible approaches to the opportunities that have presented themselves, the author summarizes the contributions to the Third Workshop on Physics and Detectors for DA{Phi}NE that deal with CP Violation and Rare Decays.
Date: January 24, 2000
Creator: Quigg, C.
Partner: UNT Libraries Government Documents Department

Measurement of sin2{beta} from J/{psi} K{sub s} decays

Description: The CP-violating parameter sin 2{beta} is directly measured using 110 pb{sup {minus}1} of data accumulated with the CDF detector at the Fermilab {anti p}p Tevatron collider operating at {radical}s = 1.8 TeV. The signal consists of 395 {+-} 31 B{sub d}{sup 0} {r{underscore}arrow} J/{psi} K{sub s} events. Three tagging methods are used to identify the type of B meson at production (B{sub d}{sup 0} or {anti B}{sub d}{sup 0}). From the CP asymmetry, sin 2{beta} is measured to be 0.79 {sub {minus}0.44}{sup +0.41}, consistent with Standard Model predictions. Sin 2{beta} is in the interval 0 {lt} sin2{beta} {lt} 1 at the 93% confidence level.
Date: January 24, 2000
Creator: Blocker, C.A.
Partner: UNT Libraries Government Documents Department

Neutrino oscillation appearance experiment using nuclear emulsion and magnetized iron

Description: This report describes an apparatus that could be used to measure both the identity and charge of an outgoing lepton in a charged current neutrino interaction. This capability in a massive detector would allow the most comprehensive set of neutrino oscillation physics measurements. By measuring the six observable transitions between initial and final state neutrinos, one would be able to measure all elements of the neutrino mixing matrix, as well as search for CP violation, and matter effects. If the measured matrix is not unitary, then one would also have an unambiguous determination of sterile neutrinos. Emulsion is considered as the tracking medium, and different techniques are discussed for the application of a magnetic field.
Date: January 24, 2000
Creator: Harris, D.A. & Para, A.
Partner: UNT Libraries Government Documents Department

The CDF Time of Flight Detector

Description: A new Time of Flight (TOF) detector based on scintillator bars with fine-mesh photomultipliers at both ends has been in operation since 2001 in the CDF experiment. With a design resolution of 100 ps, the TOF can provide separation between K{sup +-} and {pi}{sup +-} in p{bar p} collisions at the 2{omega} level for low momentum, which enhances b flavor tagging capabilities. Because of its very fast response, the TOF is an excellent triggering device, and it is used to trigger on highly ionizing particles, multiple minimum ionizing particles and cosmic rays. Particle identification is achieved by comparing the time-of-flight of the particle measured by the TOF to the time expected for a given mass hypothesis. In order to obtain the resolution necessary for particle ID, optimal calibrations are critical. This paper describes the TOF detector, its calibration procedure, the achieved resolution, the long term operation performances and some of the first results from data analysis using this detector.
Date: January 6, 2004
Creator: al., S. Cabrera et
Partner: UNT Libraries Government Documents Department

Particle identification for beauty physics

Description: We look briefly at the requirements for particle identification for possible beauty experiments at the Tevatron, both in the fixed target and the collider mode. Techniques presently in use in high energy physics experiments, and under development, should make sensitive experiments feasible. However, in all cases the present state of the art must be advanced to meet the necessary requirements for segmentation andor rate capability. The most fundamentally difficult challenges appear to be the efficient tagging of soft electrons (for the collider experiment) and the need to handle interaction rates up to /approximately/ 10/sub 9/ HZ in the fixed target mode. In both cases we can find ''in principle'' demonstrations that the requirements can be met. We have considered only the most basic prooperties of detectors, however, and the real answers will come from careful studies of details. 20 refs., 10 figs.
Date: January 1, 1987
Creator: Ludlam, T.
Partner: UNT Libraries Government Documents Department

Performance of a uranium liquid argon calorimeter

Description: We present results on the performance of a uranium and liquid argon calorimeter in the NW test beam at Fermilab. We describe the calorimeter, and discuss its performance with electrons, pions and muons from 10 GeV to 150 GeV. The performance perameters measured include response, linearity, resolution, compensation, and e/..pi.. separation.
Date: January 1, 1986
Creator: Tuts, P.M.
Partner: UNT Libraries Government Documents Department

(Search for strange quark matter and antimatter produced in high energy heavy ion collisions)

Description: This document describes the development and progress of our group's research program in high energy heavy ion physics. We are a subset of the Yale experimental high energy physics effort (YAUG group) who became interested in the physics of high energy heavy ions in 1988. Our interest began with the possibility of performing significant searches for strange quark matter. As we learned more about the subject and as we gained experimental experience through our participation in AGS experiment 814, our interests have broadened. Our program has focused on the study of new particles, including (but not exclusively) strange quark matter, and the high sensitivity measurement of other composite nuclear systems such as antinuclei and various light nuclei. The importance of measurements of the known, but rare, nuclear systems lies in the study of production mechanisms. A good understanding of the physics and phenomenology of rare composite particle production in essential for the interpretation of limits to strange quark matter searches. We believe that such studies will also be useful in probing the mechanisms involved in the collision process itself. We have been involved in the running and data analysis for AGS E814. We have also worked on the R D for AGS E864, which is an approved experiment designed to reach sensitivities where there will be a good chance of discovering strangelets or of setting significant limits on the parameters of strange quark matter.
Date: January 1, 1992
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

Hadron production in e/sup +/e/sup -/ annihilation at. sqrt. s = 29 GeV

Description: Data from the High Resolution Spectrometer at PEP have been used to study the inclusive production of baryons and mesons. Time-of-flight measurements are used to identify the charged hadrons. Neutral hadrons are identified from effective mass peaks in their decay into two charged particles. Cross sections for charged pions, charged and neutral kaons, protons and lambda hyperons are given. Other inclusive production characteristics are presented. The cross section ratios to the point cross section are: R(K/sup 0/) = 5.59 +- 0.19 +- 0.30, and for ..lambda..'s, R(..lambda..) = 0.762 +- 0.052 +- 0.064. The results, when compared to the Lund fragmentation model, give (us/ud)/(s/d) = 0.30 +- 0.10. 17 refs., 11 figs., 6 tabs.
Date: January 1, 1985
Creator: Derrick, M.; Fernandez, E.; Fries, R.; Hyman, L.; Kooijman, P.; Loos, J.S. et al.
Partner: UNT Libraries Government Documents Department

Inclusive. pi. /sup + -/, K/sup + -/, and p, anti p production in e/sup +/e/sup -/ annihilation at. sqrt. s = 29 GeV

Description: Measurements of ..pi../sup + -/, K/sup + -/ and p, anti p inclusive cross sections and fractions in e/sup +/e/sup -/ annihilation at ..sqrt..s = 29 GeV are presented. The momentum interval covered corresponds to 0.01 < z < 0.90, where z = pp/sub beam/. The analysis is based on approximately 70 pb/sup -1/ of data collected between 1984 and 1986 with the TPC2..gamma.. detector at PEP. Charged particles are identified by a simultaneous measurement of momentum and ionization energy loss (dEdx). The recently upgraded detector's momentum resolution of (..delta..pp)/sup 2/ = (1.5%)/sup 2/ + (0.65% . p (GeVc) )/sup 2/ and a dEdx resolution of typically 3.5% allow the measurements to be extended to higher z than previously reported. 70 refs., 59 figs., 7 tabs
Date: January 1, 1988
Creator: Cowan, G.D.
Partner: UNT Libraries Government Documents Department