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Review of Charm and Beauty Lifetimes

Description: A review of the latest experimental results on charm and beauty particle lifetimes is presented together with a brief summary of measurement methods used for beauty particle lifetime measurements. There have been significant updates to the D{sub s}{sup +}/D{sup 0}, B{sup +}/B{sub d}{sup 0} and {Lambda}{sub b}{sup 0}/B{sub d}{sup 0} lifetime ratios which have some theoretical implications. However more precise measurements are still needed before one can make conclusive statements about the theory used to calculate the particle lifetimes.
Date: February 5, 1999
Creator: Cheung, Harry W. K.
Partner: UNT Libraries Government Documents Department

B physics at the Tevatron Collider

Description: Precision B-physics results from the CDF and DO Collaborations based on data collected during the Tevatron 1992-96 run are presented. In particular we discuss the measurement of B hadron lifetimes, and B{sup 0} - {anti B}{sup 0} mixing results obtained using time- evolution analyses. Perspectives for the next Tevatron run, starting in 1999, are also reported.
Date: May 1, 1997
Creator: De Troconiz, J. F.
Partner: UNT Libraries Government Documents Department

Proposal for an Experiment to Measure Mixing, CP Violation and Rare Decays in Charm and Beauty Particle Decays at the Fermilab Collider - BTeV

Description: This proposal consists of five parts and two appendices. The first part provides a detailed physics justification for the BTe V experiment. The second part presents the considerations that drive the detector design, followed by a description of the detector itself. The third part summarizes our simulation results which demonstrate that the design does enable us to achieve our physics goals. The fourth part compares BTeV's physics reach to that of other experiments which will be active in B physics in the same time period. The fifth part gives a very brief, high level summary of the cost estimate for BTeV. Appendix A has additional technical details about many of the detector subsystems and R&D plans; it is intended to be read primarily by experts in each area. Appendix B contains a roadmap which describes the location in the proposal of the answers to questions posed to the BTeV collaboration by the Fermilab Program Advisory Committee in June of 1999.
Date: May 1, 2000
Creator: Kulyavtsev, A.; Procario, M.; Russ, J.; You, J.; Cumalat, J.; Appel, J. A. et al.
Partner: UNT Libraries Government Documents Department

Energy and rapidity dependence of beauty production at Tevatron

Description: The CDF and D0 experiments have measured bb production in pp interactions at {radical}s = 1800 GeV and 630 GeV (the energy at which the previous measurement was performed by the UAl experiment). The Tevatron measurements are used to evaluate, for the first time, the center-of-mass energy and rapidity dependence of b-quark production cross section measured with the same detectors. Preliminary results from these measurements are presented and compared with the next-to-leading order QCD predictions.
Date: September 1, 1997
Creator: Ba, M.M.
Partner: UNT Libraries Government Documents Department

A dedicated LHC collider Beauty experiment for precision measurements of CP-violation. LHC-B letter of intent

Description: The LHC-B Collaboration proposes to build a forward collider detector dedicated to the study of CP violation and other rare phenomena in the decays of Beauty particles. The forward geometry results in an average 80 GeV momentum of reconstructed B-mesons and, with multiple, efficient and redundant triggers, yields large event samples. B-hadron decay products are efficiently identified by Ring-Imaging Cerenkov Counters, rendering a wide range of multi-particle final states accessible and providing precise measurements of all angles, {alpha}, {beta} and {gamma} of the unitarity triangle. The LHC-B microvertex detector capabilities facilitate multi-vertex event reconstruction and proper-time measurements with an expected few-percent uncertainty, permitting measurements of B{sub s}-mixing well beyond the largest conceivable values of x{sub S}. LHC-B would be fully operational at the startup of LHC and requires only a modest luminosity to reveal its full performance potential.
Date: March 28, 1996
Creator: Crosetto, Dario B.
Partner: UNT Libraries Government Documents Department

Charm and beauty production and polarization at CDF

Description: In this paper the authors present results on Charm and Beauty production as well as on production and polarization of Quarkonia at {radical}s = 1.8 TeV. These results were obtained from data taken with the CDF detector at Fermilab. They cover recently completed analyses of the 1992--96 collider run.
Date: October 10, 2000
Creator: Papadimitriou, Vaia
Partner: UNT Libraries Government Documents Department

Inclusive dimuon and b-quark production cross sections in p{bar p} collisions at {radical}s = 1.8 TeV

Description: We report on a preliminary measurement of the inclusive dimuon cross section in p{bar p} collisions at {radical}s = 1.8 TeV using the D0 detector at the Fermilab Tevatron. From these results, we extract the inclusive b-quark production cross section for the kinematic range {vert_bar}y{sup b}{vert_bar} < 1.0 and 9 GeV/c < p{sub T}{sup b min} < 25 GeV/c. The difference in azimuthal angle in the transverse plane for dimuon pairs from b{bar b} production is also shown.
Date: July 1, 1995
Creator: Abachi, S.; Abbott, B. & Abolins, M.
Partner: UNT Libraries Government Documents Department

Recent B physics results at CDF

Description: Three recent B physics results at CDF are presented. The first analysis measures the production polarization of the {psi}(2S) from its decay into {mu}<sup>+</sup>{mu}<sup>-</sup>. The second one determines the {chi}<sub>b</sub> contribution to the {Upsilon}(1S) production. Both analyses are important tests of the Color Octet Model. The third analysis related here is a measurement of the full decay amplitudes of B<sup>0</sup> {yields} J/{psi}K<sup>*0</sup> and B<sup>0</sup><sub>s</sub> {yields} J/{psi}{phi}. This provides both a test of the factorization model and information relevant to CP violation studies in the B sector. All of the results are to be considered preliminary.
Date: July 26, 1999
Creator: Ribon, A.
Partner: UNT Libraries Government Documents Department

Searches for new physics at Tevatron

Description: This paper reviews the most recent results on searches for physics beyond the Standard Model at Tevatron. Both the collider experiments: CDF and D0 are performing a large variety of searches such as searches for scalar top and scalar bottom particles, search for new gauge bosons, search for long-lived massive particles and general searches for new particles decaying into dijets. The results, summarized here, are a selection of what obtained recently by both the collaborations using the Run II data, collected so far.
Date: March 15, 2004
Creator: Pagliarone, C.
Partner: UNT Libraries Government Documents Department

Design of a secondary-vertex trigger system

Description: For the selection of beauty and charm events with high efficiency at the Tevatron, a secondary-vertex trigger system is under design. It would operate on forward-geometry events. The system would use on-line tracking of all tracks in the vertex detector, to identify events with clearly detached secondary vertices.
Date: June 1, 1995
Creator: Husby, D.; Chew, P.; Sterner, K. & Selove, W.
Partner: UNT Libraries Government Documents Department

b quark and b hadron production in {anti p} p collisions at CDF

Description: We report on the status of {ital b} quark and {ital b} hadron production using 110 pb{sup -1} of data collected by the CDF detector between 1992 and 1995. We present the first direct measurement of the ratio of {ital b} quark cross sections at {radical}{ital s} = 630 GeV and {radical}{ital s} = 1800 GeV, and an update on the measurement of the {ital B} meson differential cross section. We also present measurements of the branching fraction for b {r_arrow} J{Psi} A, and the product of fragmentation fraction and branching fractions for the semileptonic decay b {r_arrow} {mu}{sup +}{ital e}{sup -} {nu}X. The last two equations were illegible and are a best guess to the original intent.
Date: December 31, 1996
Creator: Olsen, J.
Partner: UNT Libraries Government Documents Department

VIIth Blois Workshop summary: experimental

Description: The Blois Workshop has become a conference not just restricted to diffractive scattering, but including topics such as searches for SUSY and Higgs, measurements of the top mass and b-decays. I will mention these briefly but will mostly discuss new results (and needed future measurements) in hard diffraction at HERA and the Tevatron.
Date: October 1, 1997
Creator: Albrow, M.G.
Partner: UNT Libraries Government Documents Department

Recent Results from the Tevatron

Description: We review recent results from fixed-target and collider experiments at the Fermilab Tevatron. Among the topics discussed are jet production rates, {alpha}{sub S} measurements, the {anti d}/{anti u} ratio in the proton sea, diffraction, heavy quark physics and leptoquark searches.
Date: June 1, 1998
Creator: Demorden, L.
Partner: UNT Libraries Government Documents Department

CDF Run I B physics results

Description: The CDF Run I B physics program has been very successful, making numerous measurements over a wide variety of B physics topics. Measurements have included masses and lifetimes; discovery of the B{sub c}; B{sub s} {r_arrow} J/{psi}{phi} polarization; B{sup 0} {leftrightarrow} {bar B}{sup 0} mixing; sin (2{beta}); and rare decay limits. Recent results include a search for {Lambda}{sub b} {r_arrow} {Lambda}{gamma} and a study of B{sup 0} {r_arrow} J/{psi}K(*){sup 0} {pi}{sup +}{pi}{sup {minus}} decays. The tools and experience developed during Run I are quite valuable as CDF enters Run II.
Date: March 8, 2001
Creator: Bailey, S.
Partner: UNT Libraries Government Documents Department

D-Zero prospects for Run II physics

Description: Run II at the Tevatron will begin in the spring of 2001. With p{bar p} collisions at {radical}s = 2.0 TeV and an expected instantaneous luminosity of 2 x 10{sup 32} cm{sup -2} s{sup -1}, D0 is expected to collect an integrated luminosity of 2 fb{sup -1} in the first two years of running. The ongoing upgrade of the detector will allow the experiment not only to take full advantage of the high luminosity but will also allow for a rich B physics program at D0. In this paper the prospects for some important B physics measurements will be reviewed. These measurements include CP violation, B{sub s} mixing, rare B decays, and lifetimes and mass measurements of bottom particles such as the {Lambda}{sub b} and B{sub c}.
Date: August 24, 2001
Creator: Gutierrez, Gaston R
Partner: UNT Libraries Government Documents Department

B physics at CDF

Description: From 1992 to 1995 the CDF experiment has taken 110 pb{sup {minus}1} of p{anti p} collisions at a center-of-mass energy of 1.8 TeV. These data gave rise to a variety of important B physics measurements. Most importantly B mass, lifetime and mixing measurements, the observation of the last missing meson, the B{sub c}, and a measurement of the CP violation parameter sin 2{beta}. The highlights of those results are described and a perspective for the upcoming Run II period is given.
Date: October 10, 2000
Creator: Paus, Christoph
Partner: UNT Libraries Government Documents Department

The magnitude of the gluon condensate and the masses of c and b quarks from the families of T/{Psi} and {Upsilon} mesons

Description: It is shown that the model used by Shifman, Vainshtein, and Zakharov for the description of the experimental function R{sub c}(s) in the form of a sum of {delta}-functions and the plateau contradicts the Wilson operator expansion (O.E.) in the terms due to the gluon condensate. A QCD model with an infinite number of vector mesons does satisfy the requirements of the O.E. for masses and electronic width resonances close to the experimental values. The region of allowable values of the masses of c- and b-quarks and the gluon condensate compatible with the O.E. is obtained.
Date: November 1, 1993
Creator: Geshkenbein, B. & Morgunov, V.
Partner: UNT Libraries Government Documents Department

Jet physics and QCD tests at the Tevatron collider

Description: Results are presented detailing the status of tests of perturbative QCD in hard parton-parton collisions generated by high energy collisions of protons and antiprotons at the Fermilab Collider. Recent data fro the CDF and DO experiments are compared to Next-to-Leading Order QCD calculations in hadronic jet production, prompt photon production, jet production in events with W bosons, and b-quark production.
Date: February 1, 1994
Creator: Plunkett, R.
Partner: UNT Libraries Government Documents Department

Photoproduction of charm near threshold

Description: Charm and bottom production near threshold is sensitive to the multi-quark, gluonic, and hidden-color correlations of hadronic and nuclear wavefunctions in QCD since all of the target's constituents must act coherently within the small interaction volume of the heavy quark production subprocess. Although such multi-parton subprocess cross sections are suppressed by powers of 1/m{sub Q}{sup 2}, they have less phase-space suppression and can dominate the contributions of the leading-twist single-gluon subprocesses in the threshold regime. The small rates for open and hidden charm photoproduction at threshold call for a dedicated facility.
Date: November 1, 2000
Creator: Brodsky, S.J.; Chudakov, E.; Hoyer, P. & Laget, J.M.
Partner: UNT Libraries Government Documents Department

Direct {anti b}b production in {anti p}p collisions at {radical}s = 1.8 TeV

Description: The first measurement of bottom quark production in the forward detector at CDF is presented in this thesis. Events from the 1988/89 Fermilab collider run were selected with forward muons with nearby jets to form a bottom quark tag. The efficiency and acceptance of the detector are then taken into account and the number of events is turned into a cross section: {sigma}(p{sub t}{sup b} > 20 GeV, 1.9 < {vert_bar}{eta}{sup b}{vert_bar} < 2.5) = (124. {+-} 35. {+-} 76.) nb. The contribution from direct bottom quarks is {sigma}(p{sub t}{sup b} > 20 GeV, p{sub t}{sup {anti b}} > 15 GeV, 1.9 < {vert_bar}{eta}{sup b}{vert_bar} < 2.5) = (100. {+-} 30.{sub {minus}31.}{sup +30.}) nb.
Date: December 31, 1993
Creator: Lamoureux, J.
Partner: UNT Libraries Government Documents Department

Measurement of the charged multiplicity of Z{sup 0} {yields} b{bar b} events

Description: Using an impact parameter tag to select an enriched sample of Z{sup 0} {yields} b{bar b} events, the authors have measured the difference between the average charged multiplicity of Z{sup 0} {yields} b{bar b} and Z{sup 0} {yields} hadrons to be {bar n}{sub b} - {bar n}{sub had} = 2.24 {+-} 0.30(stat.) {+-} 0.33(syst.) tracks per event. From this, they have derived {bar n}{sub b} - {bar n}{sub uds} = 3.31 {+-} 0.41 {+-} 0.79. Comparing this measurement with those at lower center-of-mass energies, the authors find no evidence that {bar n}{sub b} - {bar n}{sub uds} depends on energy, in agreement with a precise prediction of perturbative QCD.
Date: August 1, 1994
Creator: Burrows, P. N.
Partner: UNT Libraries Government Documents Department

Heavy quark and neutrino physics. Final technical report, FY1994--FY1998

Description: This report begins with an overview of KSU history in personnel and funding, creation of infrastructure, and physics. Then brief summaries are given for the following research projects: Fermilab E653: Measuring Charm and Beauty Decays via Hadronic Production in a Hybrid Emulsion Spectrometer; Fermilab E791: Continued Study of Heavy Flavors at TPL; Fermilab E815: Precision Measurements of Neutrino Neutral-Current Interactions Using a Sign-Selected Beam; Fermilab E872/DONUT: Direct Observation of {nu}{sub {tau}}; Fermilab E803/COSMOS: Neutrino Oscillations; KSU at the Fermilab D0 collider; Muon Collider; OJI Progress Report: Multisampling Drift Chamber.
Date: December 31, 1998
Partner: UNT Libraries Government Documents Department