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Charm and beauty measurements at Fermilab fixed target

Description: Eighteen months after a successful run of the Fermilab fixed target program, interesting results from several experiments are available. This is the first time that more than one Fermilab fixed target experiment has reported the observation of beauty mesons. In this paper we review recent results from charm and beauty fixed target experiments at Fermilab.
Date: October 1, 1993
Creator: Mishra, C. S.
Partner: UNT Libraries Government Documents Department

Charmonium and bottomonium in {bar p}p interactions

Description: In this talk, I presented some examples of data from the CDF collaboration on J/{psi}, {chi}, {psi}{prime} and {Gamma} production. Such data are used to test models of production dynamics and for the understanding of rates for b quark production. I am not a member of the CDF experiment and showed their data with permission as an interested and impressed spectator. Data from D0 may be found in the talk of D. Denisov. As a complement to this data from the highest energy accelerator experiment, operating at {radical}{bar s}= 1.8 TeV, I also showed data from Fermilab experiment E760 on masses, widths, states and branching ratios in the Charmonium system, obtained by studying resonant formation of c{bar c} states in p{bar p} annihilation at {radical}{bar s} = m(c{bar c}).
Date: December 1, 1993
Creator: Pordes, S.
Partner: UNT Libraries Government Documents Department

B physics with CDF: Recent results and future prospects

Description: Using data collected during the 1992--1993 collider run, we report on measurements of the B{sup o}, B{sup +}, and B{sub s} lifetimes. We also present our revised measurement of the B{sub s} mass. Production studies involving inclusive modes decaying into J/{psi} or {psi}(2S), semileptonic decays involving D{sup o} or D*{sup +} mesons, and fully reconstructed B mesons are also presented. We present the prospects for future work with this data, as well as that being collected in the 1994--1995 collider run. Upgrades to the detector and estimates of physics capabilities for future collider runs are also presented.
Date: August 1994
Creator: Mueller, James A.
Partner: UNT Libraries Government Documents Department

Inclusive J/{psi}, {psi} (2S) and b-quark production in {bar p}p collisions at {radical}s = 1.8 TeV

Description: Inclusive J/{psi} and {psi}(2S) production has been studied in p{bar p} collisions at {radical}s = 1.8 TeV with the Collider Detector at Fermilab. The products of production cross section times the branching fraction of J/{psi}({psi}(2S)) to {mu}{sup +}{mu}{sup {minus}} are reported as functions of the J/{psi}({psi}(2S)) P{sub T} in the kinematic range P{sub T} > 6 GeV/c and {vert_bar}{eta}{vert_bar} {le} 0.5. The products of the integrated cross section times branching fraction and the b-quark production cross section calculated from these values are also reported.
Date: November 1, 1992
Creator: Papadimitriou, V. & Collaboration, CDF
Partner: UNT Libraries Government Documents Department

Inclusive J/{psi}, {psi}(2S) and b-quark production in {bar p}p collisions at {radical}s = 1.8 TeV

Description: Inclusive J/{psi} and {psi}(2S) production has been studied in {bar p}p collisions at {radical}s = 1.8 TeV using the Collider Detector at Fermilab. The products of production cross section times branching fraction have been measured as functions of P{sub T} for J/{psi}({psi}(2S)) {yields} {mu}{sup +}{mu}{sup {minus}} in the kinematic range P{sub T}{sup J/{psi}({psi}(2S))} > 6 GeV/c and {vert_bar}{eta}{sup J/{psi}({psi}(2S)){vert_bar}} {le} 0.5. The products of the integrated cross section times branching fraction are calculated and used to obtain an inclusive b-quark production cross section.
Date: November 1, 1992
Creator: Fuess, T. A. & Collaboration), (CDF
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. & Collaboration), (CDF
Partner: UNT Libraries Government Documents Department

SVX b physics prospects

Description: CDF has enhanced its capabilities for b-physics with the installation of a silicon vertex detector (SVX), which provides precise 2-dimensional tracking. The SVX impact parameter (IP) resolution ({approximately} 13{mu}m for P{sub t} {gt} 10 GeV) is well suited to detecting displaced secondary vertices (SV) from b-hadron decays (c{tau}{sub B} {approx_equal} 390{mu}m). In this paper we show evidence of SV detection using the {Psi} {yields} {mu}{sup {plus}} {mu}{sup {minus}} sample, which is b-enriched, and describe some prospects of b physics opened by the SVX with 25 pb{sup {minus}1}, the goal integrated luminosity of present run.
Date: November 1, 1992
Creator: Dell`Agnello, S. & Collaboration, The CDF
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

Mass and lifetime measurements with exclusive B reconstruction at CDF

Description: Lifetimes and masses of B mesons have been measured in exclusively reconstructed decays including J/{psi} {yields} {mu}{sup +} decays. In 19.3 pb{sup {minus}1} of {bar p}p collisions at {radical}s = 1.8 TeV taken in 19920--93 at the Fermilab Tevatron collider, approximately 300 B mesons have been fully reconstructed. The measurements require precise determination of the helical track parameters of charged particle tracks. We find M(B{sub S}{sup O}) = 5367.7 {plus_minus} 2.4 {plus_minus} 4.8 MeV/c{sup 2}, {tau}(B{sup +}) = 1.61 {plus_minus} 0.16 {plus_minus} 0.05 ps, and {tau}(B{sup O}) = 1.57 {plus_minus} 0.18 {plus_minus} 0.08 ps.
Date: July 7, 1994
Creator: Lewis, J. D.
Partner: UNT Libraries Government Documents Department

Experimental Overview

Description: Data from CERN/SPS and BNL/AGS experiments were reviewed, with emphasis on most recent results, including reactions with recently obtained Au ions.
Date: August 1, 1993
Creator: Plasil, F.
Partner: UNT Libraries Government Documents Department

Production of J/{Psi} in 800 GeV/c p-Si interactions

Description: The authors report on the analysis of high mass opposite sign dimuon states produced in pSi interactions at {radical}s = 38.7 GeV. These data have been collected with an open geometry fixed target spectrometer in the Fermilab Experiment E771. J/{psi} and {psi}(2S) total cross section sand J/{psi} x{sub f} and p{sub t} differential cross sections have been measured and compared with extrapolations from data at lower energies. Evidence for {Upsilon} meson production is also presented.
Date: July 1, 1994
Creator: Collaboration, Fermilab E771
Partner: UNT Libraries Government Documents Department

Measurement of the B{sub s} meson lifetime at CDF

Description: Proton-antiproton collision data corresponding to a total integrated luminosity of {approximately} 21 pb{sup {minus}1} were collected with the CDF detector at the Fermilab Tevatron collider during 1992--1993. The lifetime of the B{sub s} meson is measured using events from the semileptonic decay B{sub s} {yields} {ell}{sup +}{nu}D{sub s}{sup {minus}}X and from the exclusive decay B{sub s} {yields} J/{psi}{phi}. For the semileptonic decay channel, 76 {ell}{sup +}D{sub s}{sup {minus}} signal events are selected where the D{sub s} is identified via the decay D{sub s}{sup {minus}} {yields} {phi}{pi}{sup {minus}}, {phi} {yields} K{sup +}K{sup {minus}}. From this sample the B{sub s} meson lifetime is determined to be {tau}{sub s} = 1.42{sub {minus}0.23}{sup +0.27} (stat.){sub {minus}0.11}{sup +0.11} (syst.) ps. In the J/{psi}{phi} channel, 11 events are used and the lifetime is found to be {tau}{sub s} = 1.74{sub {minus}0.60}{sup +0.90} (stat.){sub {minus}0.07}{sup +0.07} (syst.) ps.
Date: June 1, 1994
Creator: Collaboration, CDF
Partner: UNT Libraries Government Documents Department

J/{psi},{psi}{prime} {r_arrow} {mu}{sup +}{mu}{sup {minus}} and B {r_arrow} J/{psi},{psi}{prime} cross sections

Description: This paper presents a measurement of J/{psi},{psi}{prime} differential cross sections in p{bar p} collisions at {radical}s = 1. 8 TeV. The cross sections are measured above 4 GeV/c in the central region ({vert_bar}{eta}{vert_bar} < 0.6) using the dimuon decay channel. The fraction of events from B decays is measured, and used to calculate b quark cross sections and direct J/{psi}, {psi}{prime} cross sections. The direct cross sections are fond to be more than an order of magnitude above theoretical expectations.
Date: June 1, 1994
Creator: Collaboration, CDF
Partner: UNT Libraries Government Documents Department

Quarkonia production, b-quark production and b{anti b} correlation studies with CDF

Description: The high rate of B{anti B} production at the Tevatron makes it a unique place for the study of B production and decay. Although e{sup +}e{sup {minus}} colliders provide a cleaner environment than hadron colliders for the study of B decays, CDF has shown that exclusive B channels can be successfully reconstructed in a harsh environment. Their data have been taken in p{anti p} collisions at {radical}s = 1.8 TeV with the CDF detector during the 1988--89 and the 1992--93 collider runs. The CDF detector has been upgraded before the start of the 1992--93 run. The authors have collected {approximately}21 pb{sup {minus}1} of data with this upgraded detector during the 1992--93 run. During the 1988--89 collider run CDF has shown that once can study quarkonia physics and b physics even in a harsh p{anti p} collider environment. The data collected with the upgraded CDF detector during the 1992--93 run are leading them to a rich program which focuses on the production and decay of quarkonia and b-quarks, and which will answer many of the questions posed during the 1988--89 collider run. Results from both runs are concluded.
Date: October 1, 1993
Creator: Papadimitriou, Vaia
Partner: UNT Libraries Government Documents Department

Measurement of the polarization in the decay B{sup 0} {yields} J/{psi}K{sup *0} in {bar p}p collisions at {radical}s = 1.8 TeV

Description: This paper reports on the measurement of the polarization in the decay B{sup o} {yields} J/{psi}K{sup *o} using data collected at the collider Detector at Fermilab in {bar p}p collisions at {radical}s = 1.8 TeV. B{sup O} mesons were reconstructed through the decay chain B{sup o} {yields} J/{psi}K{sup *o}, J/{psi} {yields} {mu}{sup +}{mu}{sup {minus}}, K{sup *o} {yields} K{sup +}{pi}{sup {minus}}. A sample of 50 {plus_minus} 11 events was used in the measurement, yielding the result {Gamma}{sub L}/{Gamma} = 0.66 {plus_minus} 0.10 (stat) {sub {minus}}0.10 {sup +0.08} (sys).
Date: May 26, 1994
Creator: CDF Collaboration
Partner: UNT Libraries Government Documents Department

Polarization of charmonium in {pi}N collisions

Description: Measurements of the polarization of J/{psi} produced in pion-nucleus collisions are in disagreement with leading twist QCD prediction were J/{psi} is observed to have negligible polarization whereas theory predicts substantial polarization. We argue that this discrepancy cannot be due to poorly known structure functions nor the relative production rates of J/{psi} and X{sub J}. The disagreement between theory and experiment suggests important higher twist corrections, as has earlier been surmised from the anomalous non-factorized nuclear A-dependence of the J/{psi} cross section.
Date: September 1, 1994
Creator: Tang, Wai-Keung
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: November 1, 1992
Creator: Burchat, P.; Dorfan, D.; Litke, A.; Heusch, C.; Sadrozinski, H.; Schalk, T. et al.
Partner: UNT Libraries Government Documents Department

Summary of the working group on tests of QCD

Description: The working group discussed several topics related to charm production that can provide important input for our understanding of QCD. It was recognized that studies of both open and hidden charm in a high-statistics experiment will be essential in order to understand the production mechanisms. Nuclear effects were also discussed and a connection was made to similar effects observed in other reactions.
Date: September 1, 1994
Creator: Papavassiliou, V.
Partner: UNT Libraries Government Documents Department

Techniques in meson spectroscopy

Description: This report contains lectures on the following topics: the quark model and beyond using quantum chromodynamics; analysis of formation reactions; energy dependence of the partial wave amplitudes; where the data for the t-matrix analysis comes from; and coupled channel analysis of isoscalar mesons.
Date: December 31, 1991
Creator: Longacre, R. S.
Partner: UNT Libraries Government Documents Department

Inclusive B production at CDF and D0

Description: We present the latest results on inclusive b production studies from CDF and D0 collaborations in p{bar p} collisions at {radical}s = 1.8 TeV at the Fermilab Tevatron Collider. The results are from recently completed analyses of 198889 data and preliminary analyses of 1992--1993 data. This report includes new b cross section measurements using semileptonic b decays to muons, J/{psi} production in dimuon events, and a study of b{bar b} correlations in e{mu} events. The new results from CDF and D0 show no major discrepancies between the Tevatron data and the NLO QCD prediction for p{sub t} values down to 6 GeV.
Date: September 1, 1994
Creator: Bazizi, K. A. & Collaborations, CDF and D0
Partner: UNT Libraries Government Documents Department

Measurement of the polarization in the decay B{sup 0} {yields} J/{psi}K*{sup 0} in {bar p}p collisions at {radical}s = 1.8 TeV

Description: We report on a measurement of data of the polarization in the decay B{sup 0} {yields} J/{psi}K*{sup 0} using data collected at the Collider Detector at Fermilab in p{bar p} collisions at {radical}s = 1.8 TeV. B{sup 0} mesons were reconstructed through the decay chain B{sup 0} {yields} J/{psi}K*{sup 0}, J/{psi} {yields} {mu}{sup +}{mu}{sup {minus}}, K*{sup 0} {yields} K{sup +}{pi}{sup {minus}}. The results, based on a sample of 60 {plus_minus} 11 events, is {Gamma}{sub L}/{Gamma} = 0.66 {plus_minus} 0.10 (stat) {sub {minus}0.10}{sup +0.08} (sys).
Date: August 1, 1994
Creator: Ohl, K. E. & Collaboration, CDF
Partner: UNT Libraries Government Documents Department

J/{psi},{psi}{prime} {yields} {mu}{sup +}{mu}{sup {minus}} and B {yields} J/{psi},{psi}{prime} cross sections

Description: This paper presents a measurement of J/{psi},{psi}{prime} differential cross sections in p{bar p} collisions at {radical}s = 1.8 TeV. The cross sections are measured above 4 GeV/c in the central region ({vert_bar}{eta}{vert_bar} < 0.6) using the dimuon decay channel. The fraction of events from B decays is measured, and used to calculate b quark cross sections and direct J/{psi},{psi}{prime} cross sections. The direct cross sections for the {psi}{prime} are found to be more than an order of magnitude above theoretical expectations.
Date: August 1, 1994
Creator: Daniels, T. & Collaboration, CDF
Partner: UNT Libraries Government Documents Department

Measurement of the B meson differential cross-sections in p{bar p} collisions at {radical}s = 1.8 TeV using the exclusive decays B{sup {plus_minus}} {yields} J/{psi}K{sup {plus_minus}} and B{sup 0} {yields} J/{psi}K*{sup 0}

Description: This paper presents the first measurement of the differential B{sup {plus_minus}}and B{sup o} cross-sections, d{sigma}/d{sub PT} in p{bar p} collisions at {radical}s = 1.8 TeV. The data sample used represents an integrated luminosity of 19.3 {plus_minus} 0.8 pb{sup {minus}1} accumulated by the Collider Detector at Fermilab (CDF). The cross-sections are measured over the PT range 6--15 GeV/c in the central pseudorapidity region {vert_bar}{eta}{vert_bar} < 1 by fully reconstructing the B meson decays B{plus_minus} {yields} and J/{psi}K{sup *o}, where the J/{psi} is required to decay to two muons, and the K{sup *o} is required to decay to K{plus_minus}{pi}{plus_minus}. The results are compared to the theoretical QCD prediction calculated at next-to-leading order.
Date: August 1, 1994
Creator: Bailey, M. W. & Collaboration, CDF
Partner: UNT Libraries Government Documents Department

Recent results on top, bottom and exotic physics at the Tevatron

Description: A summary of results from the recently concluded 1991--1993 Tevatron run is presented. Selected topics from b physics and exotic particle searches from the CDF and D0 collaborations are reviewed. Preliminary results from the CDF top search, using 12pb{sup {minus}1} from the 1992--1993 run, are given. In particular, the lepton + b-tag and dilepton analyses are discussed. Preliminary results from the CDF dilepton analysis places a lower limit on the top quark mass of 108GeV/c{sup 2} at the 95% C.L.
Date: August 1, 1993
Creator: Shaw, N. M.
Partner: UNT Libraries Government Documents Department