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in subjects: "Mass Spectra"

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Direct Electron Pair Production in pi. /sup -/p Interactions at 16 GeV/c and a Model for Direct Lepton and Photon Production at low P/sub T/

The production of prompt electron-positron pairs in 16 GeV/c ..pi../sup -/p collisions has been measured using the LASS spectrometer at SLAC. An excess of events is observed above the estimated contributions of direct and Dalitz decay of known resonances in the kinematic range defined by 0.1 less than or equal to x less than or equal to 0.45, 0 less than or equal to P/sub T/ less than or equal to 0.8 GeV/c and 0.2 less than or equal to M(e/sup +/e/sup -/) less than or equal to 0.7 GeV/c/sup 2/.… more

Date: July 1, 1981

Creator: Blockus, D.; Dunwoodie, W. & Leith, D. W. G. S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Asymmetry in the angular distribution of inclusive A baryons from e/sup +/e/sup -/ annihilations at. sqrt. s = 29 GeV

The forward-backward asymmetry A expected from the ..gamma.. - Z/sup 0/ interference term in the process e/sup +/e/sup -/ ..-->.. q anti q is observed in the lab production angular distribution of high momentum A baryons. The data were collected with the High Resolution Spectrometer at PEP and an integrated luminosity of 256 pb/sup -1/ at ..sqrt..s = 29 GeV was used in the analysis. The asymmetry is seen to increase with the fractional energy z = 2E/..sqrt..s of the A due to the decreasing pres… more

Date: May 1986

Creator: Abachi, S.; Baringer, P.; Beltrami, I.; Bylsma, B. G.; DeBonte, R.; Koltick, D. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Recent results from the lead--glass--wall experiment. [Review]

Recent results from the LGW experiment are discussed. They include: study of the psi ..-->.. 2g..gamma.. ..-->.. ..gamma.. + h decay mode, accessible thrugh the analysis of the inclusive ..gamma.. spectrum; the semi-leptonic decay mode of the D's, specifically the K--e correlation; the measurement of R/sub D anti D/, the cross section over sigma/sub ..mu mu../, for D production up to 7.8 GeV; the study of the charmed quark fragmentation function accessible through D meson spectra. 51 references. more

Date: March 1, 1979

Creator: Barbaro-Galtieri, A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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A preliminary calculation of the background to t detection with tagged bs

We investigate the utility of using tagged b jets as a probe for the top quark. We present an approximate calculation of the QCD rate at Tevatron energies for the production of six jets where one of the jets is required to contain a b quark, along with the corresponding rate involving an intermediate t{bar t} pair. With a minimal set of cuts, the signal-to-background is expected to be of order one-to-one, in contrast to the case where no jets are tagged, when the signal-to-background is at leas… more

Date: November 1, 1990

Creator: Giele, W.T.; Kosower, D.A. (Fermi National Accelerator Lab., Batavia, IL (USA)) & Kuijf, H. (Rijksuniversiteit Leiden (Netherlands). Inst. Lorentz)

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Opening the high-energy frontier

I review the scientific motivation for an experimental assault on the 1-TeV scale, elaborating the idea of technicolor as one interesting possibility for what may be found there. I then summarize some of the discovery possibilities opened by a high-luminosity, multi-TeV proton-proton collider. After a brief resume of the experimental environment anticipated at the SSC, I report on the status of the SSC R D effort and discuss the work to be carried out over the course of the next year. 37 refs.,… more

Date: December 1, 1988

Creator: Quigg, C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Particle production in Si + A and p + A collisions at 14. 6 Ater dot GeV/c

Particle production ({pi}{sup {plus minus}}, K{sup {plus minus}}, p) has been measured in both Si+A and p+A collisions at 14.6 A{center dot}GeV/c. Comparisons of m{sub t} and dn/dy distributions between p+Be, p+Au and central Si+Au collisions are discussed. 8 refs., 3 figs.

Date: January 1, 1990

Creator: Miake, Y.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Preliminary Results from the CMD-2 Detector

A new general-purpose detector CMD-2 (calorimetric magnetic detector has started experiments at the upgraded e[sup [plus]]e[sup [minus]] collider VEPP-2M (collider for electron-positron beams) at Novosibirsk. During early runs an integrated luminosity of about 400 inverse nanobarns has been collected in the center of mass energy range 400[endash]1030 MeV.

Date: 1992

Creator: Khazin, B. I.; Akhmetshin, R. R.; Aksenov, G. A.; Anashkin, E. V.; Aulchenko, V. M.; Baibusinov, B. O. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Large P sub t jets at CDF

The inclusive jet cross section and the dijet mass spectrum have been measured at the Fermilab Tevatron Collider at {radical}s = 1.8 TeV. These measurements span approximately 7 orders of magnitude in cross section and contain jets up to 400 GeV in transverse energy and dijet masses up to 950 GeV. Comparisons have been made to QCD at both orders {alpha}{sub s}{sup 2} and {alpha}{sub s}{sup 3}. 8 refs., 9 figs.

Date: May 9, 1990

Creator: Dell'Orso, M. (Pisa Univ. (Italy). Dipt. di Fisica)

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Strangeness production in S + Pb and p + Pb collisions at 200 GeV/c per nucleon

Results from CERN experiment NA36 are reported. Cross sections for the production of singly strange particles in the S+Pb and p+Pb reactions have been measured in the rapidity range 1.25<y<3.5 and for p[sub t]>0.2 GeV. A significant difference in the rapidity distributions of the lambda particles originating from these reactions suggests a fundamental difference in the strangeness production mechanism.

Date: September 1, 1992

Creator: Sakrejda, I.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Methods of chemical analysis for organic waste constituents in radioactive materials: A literature review

Most of the waste generated during the production of defense materials at Hanford is presently stored in 177 underground tanks. Because of the many waste treatment processes used at Hanford, the operations conducted to move and consolidate the waste, and the long-term storage conditions at elevated temperatures and radiolytic conditions, little is known about most of the organic constituents in the tanks. Organics are a factor in the production of hydrogen from storage tank 101-SY and represent… more

Date: February 1, 1993

Creator: Clauss, S.A. & Bean, R.M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Jet dynamics at the Tevatron collider

Results for processes involving two or more hadronic jets at {radical}s = 1800 GeV are presented. The data are compared with the results predicted from perturbative QCD. 16 refs., 10 figs.

Date: December 1, 1989

Creator: Plunkett, R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Highlights from D0

The D0 Experiment is a new, large multipurpose experiment at the Tevatron Proton-Antiproton Collider at the Fermi National Accelerator Laboratory. From the analysis of data taken during August--October, 1992, a selection of preliminary physics results will be given on inclusive jet production, direct photon production, the production and decay properties of the W and Z bosons, the search for the top quark in the dilepton and lepton + jets channels, B physics and searches for new particles.

Date: December 1992

Creator: Madaras, R. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Top quark and SUSY (supersymmetric) searches at CDF

Searches for the top quark in p{bar p} collisions at {radical}s = 1.8 TeV are described. The analyses are based on data with an integrated luminosity of 4.4 pb{sup {minus}1} recorded with the Collider Detector at Fermilab in the 1988--1989 run. An upper limit on the t{bar t} cross section is obtained. The top quark with mass below 89 GeV/c{sup 2} is excluded at the 95% CL. Prospects for searches for the top quark in the future are presented. We also briefly present results on searches for super… more

Date: May 17, 1990

Creator: Yeh, G.P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Hadronic production of J/[psi] at large [chi][sub F] in 800 GeV p+Cu and p+Be collisions

The differential cross-section d[sigma]/dx[sub F] for J/[psi] production in 800 GeV proton-nucleus collisions has been measured in the kinematic range 0.30 [le] x[sub F] [le] 0.95 and x[sub F] [lt] p[perpendicular] [lt] 5 GeV through the decay mode J/[psi] [yields] [mu][sup +][mu][sup [minus]]. The nuclear dependence of J/[psi] production over this range was measured using copper and beryllium targets. The differential cross sections are in good agreement with the predictions of the symbolical … more

Date: December 1, 1992

Creator: Kowitt, M.S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Charm lifetime measurements from TASSO

Recent measurements by TASSO of the lifetimes of charmed mesons is reviewed. The lifetime reported for the D/sub s/ meson utilizes the entire data sample collected. The lifetime of the neutral charmed meson, D/sup o/, is from a subsample of the total data set. Special emphases is given to the experimental procedures used.

Date: October 9, 1987

Creator: Forden, G. E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Test of QED using a laser at the SLAC final focus test beam

Experiment {number sign}144 at SLAC has three parts: the search for low-mass states excited in {gamma}{gamma} collisions and observed in pair decay, the study of nonlinear, nonperturbative QED in {gamma}e and {gamma}{gamma} collisions, and its possible applications to general purpose linear colliders. Such colliders could produce the full range of J{sub q{center dot}{center dot}{bar q}}/{sup PC} states, leptoquarks J{sub l{center dot}{center dot}{bar q}}/{sup PC}, the particles of supersymmetry… more

Date: April 1, 1992

Creator: Spencer, J.E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Study of the radiative decay J/psi. -->. gamma. eta. pi. /sup +/. pi. /sup -/

The Mark III collaboration has performed a high statistics study of the reaction J/psi ..-->.. ..gamma..eta..pi../sup +/..pi../sup -/, with two different final states of the eta, eta ..-->.. ..gamma gamma.. and eta ..-->.. ..pi../sup 0/..pi../sup +/..pi../sup -/. Both modes have a broad structure from 1.2 to 1.9 GeV/c/sup 2/ and two structures, which decay via delta/sup + -/..pi../sup - +/, delta/sup + -/ ..-->.. eta..pi../sup + -/, are identified at 1.28 and 1.39 GeV/c/sup 2/. No signal is obs… more

Date: February 1, 1987

Creator: Becker, J. J.; Blaylock, G. T.; Bolton, T.; Brown, J. S.; Bunnell, K. O.; Burnett, T. H. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

In search of K/sup +/. -->. pi. /sup +/. mu. /sup +/e/sup -/ and other rarities seldom or never before seen

The progress of AGS Experiment 777, a search for K/sup +/ ..-->.. ..pi../sup +/..mu../sup +/e/sup -/ is described. Results on the decay K/sup +/ ..-->.. ..pi../sup +/A/sup 0/, where A/sup 0/ is a weakly interacting neutral particle that decays into e/sup +/e/sup -/ and preliminary results on the direct decay K/sup +/ ..-->.. ..pi../sup +/e/sup +/e/sup -/ are presented as well as new limits on ..pi../sup 0/ ..-->.. ..mu../sup +/e/sup -/. 12 refs., 5 figs.

Date: January 1, 1988

Creator: Lazarus, D. M.; Gordon, H. A.; Rehak, P.; Cooper, P. S.; Egger, J.; Herold, W. D. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Three-Family Top Quark Mass Spectrum

We expand upon our previous Monte-Carlo-type study of 3-family mass matrices which lead to the experimentally-determined KM matrix and satisfy the constraints imposed by B{sub d}--{bar B}{sub d} mixing, {vert bar}V{sub ub}/V{sub cb}{vert bar}, B{sub K} and CP violation. Scatter distributions in {vert bar}V{sub ub}V{sub cb}{vert bar}, {epsilon}{prime}/{epsilon} and x{sub s} vs m{sub t} are presented for the standard minimal Higgs structure as well as top quark mass histograms for the minimal and… more

Date: May 1990

Creator: Albright, Carl H.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Quenched Hadron Spectrum of QCD

We calculate hadron spectrum of quantum chromodynamics without dynamical fermions on a 32[sup 3] [times] 64 lattice volume at [beta] = 6.5. Using two different wall sources of staggered fermion whose mass is 0.01, 0.005 and 0.0025 under the background gauge configurations, we extract local light hadron masses and the [triangle] masses and compare these hadron masses with those from experiments. The numerical simulation is executed on the Intel Touchstone Delta computer. We employ multihit metro… more

Date: December 1, 1992

Creator: Kim, Seyong

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Role of preasphaltenes in coal conversion reactions. Second quarterly report, year two

The plans for the second year in the present contract called for application of analytical methods developed in the first year to the elucidation of the role of preasphaltenes in the coal conversion processes. As introduced and discussed in the last quarterly report, recent experiments have demonstrated the necessity of also studying the influence of weathering processes on coal structures and reactivity especially in regard to the production of preasphaltene-rich, short contact time (SCT) pyro… more

Date: January 1, 1984

Creator: Hill, G.R.; Meuzelaar, H.L.C.; Futrell, J.H. & Harper, A.M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Models of high energy nuclear collisions

The discussion covers nuclear collisions at relativistic energies including classes of high energy nucleus--nucleus collisions, and the kinetics of a central collision; and the asymptotic hadron spectrum including known and unknown hadrons, the relevance of the spectrum and the means of its study, thermodynamics of hadronic matter, examples of hadronic spectra, the temperature, composition of the initial fireball and its expansion, isoergic expansion with no pre-freezeout radiation, isentropic … more

Date: June 1, 1978

Creator: Glendenning, N.K.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Recent heavy ion results from CERN and Brookhaven

Results of the first round of ultrarelativistic heavy ion experiments at CERN and BROOKHAVEN are reviewed. The experiments measure global variables such as transverse energy and multiplicity to characterize the impact parameter of the collisions and compare with geometrical models of heavy ion collisions. Charged particle transverse momentum spectra are measured, and p-nucleus and nucleus-nucleus collisional look rather similar. The hardening of the spectrum at high p/sub t/, previously observe… more

Date: January 1, 1988

Creator: Jacak, B.V.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Hadron production in e/sup +/e/sup -/ annihilation at PEP

Recent results from PEP on quark and gluon fragmentation are reviewed. Topics include: inclusive stable particle production and resonance production, particle distributions in jets, heavy quark fragmentation, flavor correlation studies and tests of fragmentation models. 37 references.

Date: May 1, 1984

Creator: Hofmann, W.

Item Type: Article

Partner: UNT Libraries Government Documents Department