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Strangeonium production from LASS

Description: Results from recent studies of strangeonium mesons produced in the LASS spectrometer by an 11 GeV/c K{sup {minus}} beam are presented. Data fro new analyses of K*{bar K}*, {phi}{phi}, and {eta}{pi}{pi} final states are described. Comparisons are made with results from other hadroproduction, radiative J/{Psi} decay, and {gamma}{gamma} experiments. 24 refs., 5 figs., 2 tabs.
Date: November 1, 1990
Creator: Aston, D.; Bienz, T.; Bird, F.; Dunwoodie, W.; Johnson, W.B.; Kunz, P. et al.
Partner: UNT Libraries Government Documents Department

Experimental review of J/psi decays

Description: This is a review of J/psi physics from e/sup +/e/sup -/ colliders presented at the Charm Workshop in Beijing, China. The review includes a brief historical summary of J/psi physics, a general discussion of theoretical models and detailed results on radiative and hadronic J/psi decays from the Mark III, DM2, Crystal Ball and MARK II groups. 119 refs., 13 figs., 10 tabs.
Date: September 1, 1987
Creator: Toki, W.H.
Partner: UNT Libraries Government Documents Department

Nuclear effects in Drell-Yan and quarkonium production in proton-nucleus collisions

Description: A precise measurement of the atomic mass dependence of dimuon production induced by 800 GeV protons incident on targets of {sup 2}H, C, Ca, Fe, and W is reported. The relative Drell-Yan yield per nucleon, R = Y{sub A}/Y{sub 2{sub H}}, is sensitive to modifications of the antiquark sea in nuclei. No effect is seen for the range of target-quark momentum fraction, 0.1 < x{sub t} < 0.3. For x{sub t} < 0.1 the ratio is slightly less than unity for the heavy nuclei. These results are compared with the predictions of EMC models. A depletion of the yield per nucleon from heavy nuclei is observed for both J/{psi} and {psi}{prime} production. This depletion exhibits a strong dependence of x{sub F} and p{sub t}. Within experimental errors the depletion is the same for the J/{psi} and the {psi}{prime}. 41 refs., 6 figs.
Date: January 1, 1990
Creator: Peng, J.C.; Alde, D.M.; Baer, H.W.; Carey, T.A.; Garvey, G.T.; Klein, A. et al.
Partner: UNT Libraries Government Documents Department

Physics with nuclei at high energies

Description: Physics with nuclei at high energy is not reducible to a superposition of interactions involving individual nucleons; rather, qualitatively new phenomena show up. This is what one concludes from recent data on dilepton production off nuclei and on elastic proton-nucleus scattering. Furthermore, recent analyses of ion collisions at BNL and CERN reveal a number of non-conventional features. The relevant contributions to this Rencontre are summarized here. 37 refs., 16 figs.
Date: August 1, 1989
Creator: Geist, W.M.
Partner: UNT Libraries Government Documents Department

Getting maximum information from incomplete data on B yields charmonium-K sub S decays

Description: Tests of CP violation using B decays into CP eigenstates can be improved by using events normally rejected because of incomplete information. A search for lepton asymmetry in decays {Upsilon}(4S) {yields} B + {bar B} {yields} (K{sub S} + J/{psi}) + (lepton {sup {plus minus}} + X) can be improved by including other (c{bar c})K{sub S} events where the (c{bar c}) pair is not bound in a J/{psi} but in some other state like {psi}{prime} or {eta}{sub c} and where the lepton asymmetry is predicted to be the same as for (K{sub S} + J/{psi}), other (c{bar c})K{sub S} events which are not fully reconstructed and (c{bar c})K{sub L} events where the K{sub L} pair is not detected and which are predicted to have the opposite lepton asymmetry from corresponding K{sub S} events. The information from these additional events can give improved statistics if suitable cuts can be found to improve signal/noise. The opposite asymmetry predicted for K{sub L} events can test spurious lepton asymmetries due to systematic errors. 3 refs.
Date: September 18, 1989
Creator: Lipkin, H.J.
Partner: UNT Libraries Government Documents Department

Recent results and future prospects for the polarized beam at Fermilab

Description: We summarize activities concerning the Fermilab polarized beams. They include a brief description of the polarized-beam facility, measurements of beam polarization by polarimeters, asymmetry measurements in the {pi}{degree} production at high p{sub {perpendicular}} and in the {Lambda} ({Sigma}{degree}), {pi}{sup {plus minus}}, {pi}{degree} production at large x{sub F}, and {Delta}{sigma}{sub L}(pp, {anti p}p) measurements (Fermilab E-704). In the future we plan to investigate the proton-spin crisis by determining the gluon spin distribution in inclusive production of direct gamma, {chi}2, and J/{psi}. 20 refs., 5 figs.
Date: January 1, 1990
Creator: Yokosawa, A.
Partner: UNT Libraries Government Documents Department

Progress toward identification of gluonic states

Description: Progress in the last two years toward identification of gluonic states is reviewed. Discovery of additional pseudoscalars tends to confirm the glueball interpretation of iota(1460). A variety of evidence indicates new physics in the J = 1 channel in the E mass region. 65 refs., 1 tab.
Date: May 29, 1987
Creator: Chanowitz, M.S.
Partner: UNT Libraries Government Documents Department

Strangeonia and kin; new results from kaon hadroproduction with LASS

Description: Recent results from a high statistics study of strangeonium mesons produced in LASS by an 11 GeV/c K{sup -} beam are reviewed and compared with the quark model. New data from a variety of final states (K*{ovr K*}, {phi}{phi}, {phi}{pi}{sup 0}) produced by hypercharge exchange are described, and compared with results from other hadroproduction modes and from J/{psi} decay. 17 refs., 12 figs.
Date: December 1, 1989
Creator: Aston, D.; Bienz, T.; Bird, F.; Dunwoodie, W.; Johnson, W.B.; Kunz, P. et al.
Partner: UNT Libraries Government Documents Department

New results on hypercharge exchange reactions from LASS

Description: New results from a number of final states ({eta}{pi}{sup {minus}}{pi}{sup +},{bar K}*K*,{phi}{phi}) produced by hypercharge exchange in LASS by an 11 GeV/cK{sup {minus}} beam are described, and compared with results from other hadroproduction modes and from G/{psi} decay.
Date: November 1, 1990
Creator: Aston, D.; Bienz, T.; Dunwoodie, W.; Johnson, W.B.; Kunz, P.; Kwon, Y. et al.
Partner: UNT Libraries Government Documents Department

J sup P = 1 sup minus radial excitations from LASS data

Description: The experimental status of the strange 1 {sup {minus}} mesons is briefly reviewed and compared with the non-strange sector and quark model expectations. The results described are taken from a 4.1 event/nb exposure of the LASS spectrometer to an 11 GeV/e K{sup {minus}} beam.
Date: December 1, 1991
Creator: Aston, D.; Bienz, T.; Bird, F.; Dunwoodie, W.; Johnson, W.B.; Kunz, P. et al.
Partner: UNT Libraries Government Documents Department

An amplitude analyses of the K K-bar system (M < 2 GeV/C sup 2 ) produced in J/. Psi. radiative decay

Description: Using the 5.8 {times} 10{sup 6} J/{psi} events collected by the MARK 3 experiment on the SPEAR e{sup +}e{sup {minus}} storage ring at SLAC, a mass independent amplitude analysis of the J/{psi} {yields} {gamma} K{sub s}K{sub s} and J/{psi} {yields} K{sup +}K{sup {minus}} decays is presented. For K{bar K} systems having mass less than 2 GeV/c{sup 2}, the efficiency-corrected spherical harmonic moments of the J/{psi} joint decay angular distribution are measured. Fits are then performed in each independent mass interval in order to extract the underlying helicity amplitude structure; amplitudes describing K{bar K} systems of spin zero and spin two are included simultaneously. For the first time, a large spin zero component in the {theta}(1720) mass region is observed; consistent results are obtained for the data samples corresponding to the individual decay modes. This structure is attributed to the production of an S wave resonance, the f{sub 0}(1710), of mass and width M = 1710 {plus minus} 10 MeV/c{sup 2}, {Gamma} = 186 {plus minus} 30 MeV/c{sup 2}, respectively, with branching fraction Bf(J/{psi} {yields} {gamma}f{sub 0}, f{sub 0} {yields} K{bar K}) = (6.47 {plus minus} 1.14 {plus minus} 0.84) {times} 10{sup {minus}4}. A small amount ({approximately}24%) of spin two component in this mass region cannot be ruled out with the present statistics. These results revise the previous conclusion that the {theta}(1720) is a spin two resonance, a result obtained on the basis of spin hypothesis tests, which assumed that either pure spin zero or pure spin two states contribute in this mass region, but not both. The previous measurements of the f{sub 2}{prime} (1525) have been refined in the present analysis because of the simultaneous inclusion of spin zero and spin two amplitudes in the fit.
Date: November 1, 1991
Creator: Chen, Liang-Ping.
Partner: UNT Libraries Government Documents Department

Measurement of the bottom quark cross section in [bar p]-p collisions using the exclusive decay B[sup 0] [yields] J/[psi]K[sup 0]*

Description: A measurement of the b quark cross section in pp collisions is presented for b quarks with PT above 11.5 GeV/c and rapidity [parallel]y[parallel] < 1.0. The measurement is based on reconstruction of the exclusive decay B[sup o] [yields] J/[psi] K[sup o] in data taken with the CDF detector in the 1988-1989 Collider run. The measurement is compared to other CDF preliminary results and to theoretical predictions.
Date: November 1, 1992
Creator: Vejcik, S. (Michigan Univ., Ann Arbor, MI (United States))
Partner: UNT Libraries Government Documents Department

Highlights from CDF

Description: After a hiatus of 3 years, CDF is again taking data. Many of the upgrades made to the detector during this period are described here, along with some preliminary indications of their performance. A brief survey of the new data is presented. Prospects for the current run are discussed.
Date: November 1, 1992
Creator: Yagil, A.
Partner: UNT Libraries Government Documents Department

Santa Cruz Institute for Particle Physics (SCIPP)

Description: Work for the coming year is a logical continuation of the efforts of the past year. Some special highlights of this past year which are discusses in more detail in this report are: (1) The move onto beamline and start of ZEUS data taking. (2) The completion of the SDC technical proposal including a detailed long-term plan for construction. (3) Continuing publication of very detailed physics results from ALEPH concerning [tau] and b physics, and a precision measurement of electroweak and QCD parameters. (4) Completion of very successful data taking for E-791 at Fermilab, with nearly twice as many events recorded as initially proposed. (5) First measurement of beam polarization at the SLC. These efforts have led to about 15 physics publications this past year centered mainly on topics related to QCD, couplings of flavors to the Z[degrees], and heavy flavor decays. Taken as a whole, the results in jets from LEP, the ratio of hadronic to leptonic decays of the [tau] the leptonic branching fraction of the J/[psi], and the charmonium mass spectrum provide a very consistent set of values of [alpha][sub s] at a variety of scales. In particular, they show the running of [alpha][sub s] by a factor of about three from m[sub r] to m[sub z]. Results from LEP also provide evidence of the triple gluon vertex. Similarly, the measurement of the b[bar b] fraction of Z[degrees] decays, from the MARK II as well as LEP, provide increasingly better measurements of the Z[degree] coupling to b quarks. Combined with earlier precision measurements of the Z[degrees] mass, width, and leptonic branching fractions, the Z[degrees] decays continue to provide a very precise verification of the Standard Model.
Date: January 1, 1992
Creator: Burchat, P.; Dorfan, D.; Litke, A.; Heusch, C.; Sadrozinski, H.; Schalk, T. et al.
Partner: UNT Libraries Government Documents Department

Nuclear effects in J//psi/ and lepton-pair production

Description: High-energy processes in nuclear media provide important tests of quantum chromodynamics, since in principle one can use the nuclear environment to perturb and study the mechanisms involved in confinement and hadronization. In this talk several examples of nuclear effects in QCD will be discussed that affect the propagation and hadronization of quarks and gluons in nuclear matter. The issues include: possible signatures for quark-gluon plasma formation in heavy ion collisions, particularly J//psi/ production; hadronization due to jet coalescence; the limits of validity of QCD factorization formulae due to initial- and final-state interactions; formation zone physics; shadowing of the quark and gluon structure functions of nuclei; and color transparency in hard quasielastic reactions inside of nuclei. 29 refs., 4 figs.
Date: September 1, 1988
Creator: Brodsky, S.J.
Partner: UNT Libraries Government Documents Department

Novel spin effects in quantum chromodynamics

Description: This report discusses a number of interesting hadronic spin effects which test fundamental features of perturbative and non-perturbative QCD. These include constraints on the shape and normalization of the polarized quark and gluon structure functions of the proton; the principle of hadron helicity retention in high x[sub F] inclusive reactions; predictions based on total hadron helicity conservation in high momentum transfer exclusive reactions; the dependence of nuclear structure functions and shadowing on virtual photon polarization; and general constraints on the magnetic moment of hadrons. I also will discuss the implications of several measurements which are in striking conflict with leading-twist perturbative QCD predictions, such as the extraordinarily large spin correlation A[sub NN] observed in large angle proton-proton scattering, the anomalously large [rho][pi] branching ratio of the J/[psi], and the rapidly changing polarization dependence of both J/[psi] and continuum lepton pair hadroproduction observed at large x[sub F].
Date: February 1, 1993
Creator: Brodsky, S.J.
Partner: UNT Libraries Government Documents Department

Inclusive [chi][sub c] production in [bar p]p collisions at [radical]s = 1. 8 TeV

Description: We report the full reconstruction of X, mesons through the decay chain [chi][sub c] [yields] J/[psi][gamma], J/[psi] [yields] [mu][sup +][mu][sup [minus]], using data obtained at the Collider Detector at Fermilab in [bar p]p collisions at [radical]s = 1.8 TeV. This sample, the first observed at a hadron collider, is then used to measure the [chi][sub s] meson production cross section times branching fractions. We obtain [sigma] [center dot] Br = 3.2 [plus minus] 0.4(stat) [plus minus] 1.1(syst) nb for [chi][sub s], mesons with P[sub T] > T.0 GeV/c[sup 2] and pseudorapidity [vert bar][eta][vert bar] < 0.5. From this and the inclusive J/ [psi] cross section we calculate the inclusive b-quark crow section.
Date: November 1, 1992
Creator: Boswell, C.M. (Johns Hopkins Univ., Baltimore, MD (United States). Dept. of Physics and Astronomy)
Partner: UNT Libraries Government Documents Department

Future opportunities for hadron spectroscopy at the MPS

Description: Before I go into detailed MPS experiments, I will give a summary of the status of lattice gauge calculations of glueball masses plus glueball and hybrid masses from the bag model, and the flux tube model. For the following discussion, I am going to assume that multi-quark states or molecules are best described in terms of the MIT bag model of Jaffe with its spectrum best defined by work done by R.L. Jaffe and F.E. Low using a method called The P-Matrix. Using this method one sees that all 4-quark states will appear as very broad continuum like effects that one would not associate with meson resonances, except for the S* and the delta which forms a very special threshold K/bar K/ bound systems. There is a possibility that the E(1420) may also be related to the J/sup PC/ = 1/sup + +/, qq/bar q//bar q/ spectrum having its width narrowed by a final state interaction.
Date: December 7, 1988
Creator: Longacre, R.S.
Partner: UNT Libraries Government Documents Department

Production and phenomenology of glueballs

Description: After a brief introduction, the current status of the prominent glueball candidates are reviewed. In particular, we present a partial wave analysis of 6658 events of the reaction ..pi../sup /minus//p ..-->.. /phi//phi/n at 22 GeV/c. The data analysis reveals three resonances g/sub T/(2010), g/sub T'/(2300) and g/sub T/double prime//(2340), all with the same quantum numbers I/sup G/J/sup PC/ = 0/sup +/2/sup + +/ which comprise virtually all the production cross section. The large /phi//phi/n signal occurs over a mostly structureless and incoherent /phi/K/sup +/K/sup /minus// background. The absence of the expected OZI suppression, and the striking differences of these states from conventional states and background in other channels has so far only been successfully explained by assuming they are produced by 1-3 J/sup PC/ = 2/sup + +/ glueballs (multigluon resonances). The forthcoming search for an exotic J/sup PC/ glueball is also discussed. 20 refs., 15 figs., 1 tab.
Date: January 1, 1988
Creator: Chan, Chang S. & Lindenbaum, S.J.
Partner: UNT Libraries Government Documents Department

Proceedings of the third workshop on experiments and detectors for a relativistic heavy ion collider (RHIC)

Description: This report contains papers on the following topics: the RHIC Project; summary of the working group on calorimetry; J//Psi/ measurements in heavy ion collisions at CERN; QCD jets at RHIC; tracking and particle identification; a 4..pi.. tracking spectrometer for RHIC; Bose-Einstein measurements at RHIC in light of new data; summary of working group on read-out electronics; data acquisition for RHIC; summary of the working group on detector simulation; B-physics at RHIC; and CP violation revisited at BNL, B-physics at RHIC.
Date: January 1, 1988
Creator: Shivakumar, B. & Vincent, P.
Partner: UNT Libraries Government Documents Department

Fermilab Physics Program for the 1990's

Description: Following a brief introduction to Fermilab facilities and a review of the accelerator status and plans, the physics potential for the Fermilab III upgrade program is discussed for both the fixed target and collider modes.
Date: October 15, 1990
Creator: Stanfield, K. C.
Partner: UNT Libraries Government Documents Department

Top quark and SUSY (supersymmetric) searches at CDF

Description: 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 supersymmetric particles. 14 refs., 10 figs.
Date: May 17, 1990
Creator: Yeh, G.P.
Partner: UNT Libraries Government Documents Department

Anti-proton annihilation in nuclei as a probe of QCD

Description: Anti-proton annihilation in a nuclear target can test many novel aspects of quantum chromodynamics. In this talk I discuss a number of interesting features of such processes, including the formation of nuclear-bound quarkonium, tests of color transparency in hard, quasi-elastic nuclear reactions, higher-twist, coherent, and formation zone effects in hard inclusive nuclear reactions, reduced amplitude predictions for exclusive nuclear amplitudes, and color filter effects inclusive open and hidden charm production in nuclei. 43 refs., 6 figs., 2 tabs.
Date: September 1, 1990
Creator: Brodsky, S.J.
Partner: UNT Libraries Government Documents Department