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The discovery of the b quark at Fermilab in 1977: The experiment coordinator`s story

Description: I present the history of the discovery of the Upsilon ({Upsilon}) particle (the first member of the b-quark family to be observed) at Fermilab in 1977 by the CFS (Columbia-Fermilab-Stony Brook collaboration) E288 experiment headed by Leon Lederman. We found the first evidence of the {Upsilon} in November 1976 in an early phase of E288. The subsequent discovery in the spring of 1977 resulted from an upgraded E288 the {mu}{mu}II phase, optimized for dimuons, with about 100 times the sensitivity of the previous investigatory dimuon phase (which had been optimized for dielectrons). The events leading to the discovery, the planning of {mu}{mu}II and the running, including a misadventure (the infamous Shunt Fire of May 1977), are described. Some discussions of the aftermath, a summary, and an acknowledgement list end this brief historical note.
Date: December 1, 1997
Creator: Yoh, J.
Partner: UNT Libraries Government Documents Department

Realizing the potential of quarkonium

Description: I recall the development of quarkonium quantum mechanics after the discovery of {Upsilon}. I emphasize the empirical approach to determining the force between quarks from the properties of c{anti c} and b{anti b} bound states. I review the application of scaling laws, semiclassical methods, theorems and near-theorems, and inverse- scattering techniques. I look forward to the next quarkonium spectroscopy in the B{sub c} system.
Date: July 1, 1997
Creator: Quigg, C.
Partner: UNT Libraries Government Documents Department

Update on onium masses with three flavors of dynamical quarks

Description: We update results presented at Lattice 2005 on charmonium masses. New ensembles of gauge configurations with 2+1 flavors of improved staggered quarks have been analyzed. Statistics have been increased for other ensembles. New results are also available for P-wave mesons and for bottomonium on selected ensembles.
Date: January 1, 2006
Creator: Gottlieb, Steven A.; Levkova, L.; U., /Indiana; Di Pierro, Massimo; U., /DePaul; El-Khadra, Aida Xenia et al.
Partner: UNT Libraries Government Documents Department

QUARKONIA IN A DECONFINED GLUONIC PLASMA.

Description: We discuss lattice results on the properties of finite momentum cliarmonium states in a gluonic plasma. We also present preliminary results for bottomonium correlators and spectral functions in the plasma. Significant modifications of {chi}{sub b{sub 0.1}} states are seen at temperatures of 1.5 T{sub c}.
Date: October 24, 2005
Creator: Datta, S.; Jakovac, A.; Karsch, F. & Petreczky, P.
Partner: UNT Libraries Government Documents Department

Recent Bottomonium Results from BaBar and Belle

Description: Selected studies in bottomonium physics carried out by the BaBar and Belle experiments are presented. They include a study of radiative bottomonium transitions using {gamma} {yields} e{sup +}e{sup -} conversions done by BaBar, the search for the h{sub b}(1P) and h{sub b}(2P) states leading to an evidence for the h{sub b}(1P) seen by BaBar in {Upsilon}(3S) {yields} {pi}{sup 0} h{sub b} decay and to the Belle observation of both the h{sub b}(1P) and the h{sub b}(2P) in the reaction e{sup +}e{sup -} {yields} {pi}{sup +}{pi}{sup -} h{sub b}(1P,2P) from {Upsilon}(5S) data.
Date: June 25, 2012
Creator: Ziegler, Veronique
Partner: UNT Libraries Government Documents Department

Onium and b production at the Tevatron

Description: Recent data from the CDF and D0 experiments at the Tevatron are presented on b quark production cross sections, J/{psi}, {psi}{prime} and {Upsilon} production cross sections. An analysis from CDF of the production polarization of the J/{psi}, {psi}{prime} and {Upsilon}(1S) is reviewed and the results discussed in the context of the color octet model.
Date: January 27, 2000
Creator: Sumorok, K.
Partner: UNT Libraries Government Documents Department

W and Z properties at the Tevatron

Description: The authors present recent results from CDF and D0 on W and Z production cross sections, the width of the W boson, {tau}-e universality in W decays, trilinear gauge boson couplings, and on the observation of Z {r{underscore}arrow} b{anti b}.
Date: January 26, 2000
Creator: Ellison, J.
Partner: UNT Libraries Government Documents Department

Quarkonia production with leptons and hadrons

Description: We discuss current issues and present the latest measurements on quarkonia production from experiments monitoring hadron-hadron and lepton-hadron collisions. These measurements include cross section and polarization results for charmonium and bottomonium states.
Date: June 9, 2004
Creator: Papadimitriou, V.
Partner: UNT Libraries Government Documents Department

Decays rates for S- and P-wave bottomium

Description: The authors use the Bodwin-Braaten-Lepage factorization scheme to separate the long- and short-distance factors that contribute to the decay rates of {Upsilon}, {eta}{sub b} (S-wave) and {chi}{sub b},h{sub b} (P-wave). The long distance matrix elements are calculated on the lattice in the quenched approximation using a non-relativistic formulation of the b quark dynamics.
Date: November 1, 1994
Creator: Bodwin, G. T.; Kim, S. & Sinclair, D. K.
Partner: UNT Libraries Government Documents Department

Bottomonium Results By BaBar

Description: Summary: Observation of {eta}{sub b}; Energy scan above {Upsilon}(4S); Search for {Upsilon} {r_arrow} {gamma}A{sup 0}, A{sup 0} {r_arrow} invisible; Hadronic transitions {Upsilon}(4S) {r_arrow} {Upsilon}(nS).
Date: April 3, 2012
Creator: Tosi, Silvano & /Genoa U. /INFN, Genoa
Partner: UNT Libraries Government Documents Department

Observation of the Bottomonium Ground State in the Decay Y(3S) to ynb

Description: The authors report the results of a search for the bottomonium ground state {eta}{sub b}(1S) in the photon energy spectrum with a sample of (109 {+-} 1) million of {Upsilon}(3S) recorded at the {Upsilon}(3S) recorded at the {Upsilon}(3S) energy with the BABAR detector at the PEP-II B factory at SLAC. They observe a peak in the photon energy spectrum at E{sub {gamma}} = 921.2{sub -2.8}{sup +2.1}(stat) {+-} 2.4(syst) MeV with a significance of 10 standard deviations. They interpret the observed peak as being due to monochromatic photons from the radiative transition {Upsilon}(3S) {yields} {gamma} {eta}{sub b}(1S). This photon energy corresponds to an {eta}{sub b}(1S) mass of 9388.9{sub -2.3}{sup +3.1}(stat) {+-} 2.7(syst) MeV/c{sup 2}. The hyperfine {Upsilon}(1S)-{eta}{sub b}(1S) mass splitting is 71.4{sub -3.1}{sup +2.3}(stat) {+-} 2.7(syst) MeV/c{sup 2}. The branching fraction for this radiative {Upsilon}(3S) decay is estimated to be (4.8 {+-} 0.5(stat) {+-} 1.2(syst)) x 10{sup -4}.
Date: July 11, 2008
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

A Study of Radiative Bottomonium Transitions using Converted Photons

Description: The authors use (111 {+-} 1) million {Upsilon}(3S) and (89 {+-} 1) million {Upsilon}(2S) events recorded by the BABAR detector at the PEP-II B-factory at SLAC to perform a study of radiative transitions betwen bottomonium states using photons that have been converted to e{sup +}e{sup -} pairs by the detector material. They observe {Upsilon}(3S) {yields} {gamma}{chi}{sub b0,2}(1P) decay, make precise measurements of the branching fractions for {chi}{sub b1,2}(1P, 2P) {yields} {gamma}{Upsilon}(1S) and {chi}{sub b1,2}(2P) {yields} {gamma}{Upsilon}(2S) decays, and search for radiative decay to the {eta}{sub b}(1S) and {eta}{sub b}(2S) states.
Date: August 15, 2011
Creator: Lees, J.P.; Poireau, V.; Prencipe, E.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J. et al.
Partner: UNT Libraries Government Documents Department

Quarkonium States at B-Factories

Description: An overview is given on recent progress in the study of quarkonium spectroscopy at the B-factories. In particular, an updated status report is presented of the long list of 'charmonium-like' resonances newly discovered, whose assignment as true charmonium states is in most cases at least controversial. Also, new measurements on the decay properties of bottomonium states above open-B production thresholds are shown. Much of the progress attained in recent years in the study of the quarkonium spectra is owed to the measurements performed at B-factories. The impressive amount of data recorded by the BABAR and Belle experiments has made it possible to study rare decay chains and to look for as yet undiscovered resonances in the charmonium and bottomonium mass regions. Results presented here are based on different subsamples of the full datasets recorded up to now by the two experiments, corresponding to integrated luminosities of about 430 fb{sup -1}(BABAR - final) and about 850 fb{sup -1}(Belle). Significant contributions also come from the analysis of the various data samples recorded by the CLEO detector.
Date: November 21, 2011
Creator: Robutti, Enrico & /INFN, Genoa
Partner: UNT Libraries Government Documents Department

Study of di-pion Bottomonium Transitions and Search for the h_b(1P) State

Description: We study inclusive di-pion decays using a sample of 108 x 10{sup 6} {Upsilon}(3S) events recorded with the BABAR detector. We search for the decay mode {Upsilon}(3S) {yields} {pi}{sup +}{pi}{sup -}h{sub b} (1P) and find no evidence for the bottomonium spin-singlet state h{sub b}(1P) in the invariant mass distribution recoiling against the {pi}{sup +}{pi}{sup -} system. Assuming the h{sub b}(1P) mass to be 9.900 GeV/c{sup 2}, we measure the upper limit on the branching fraction {Beta}[{Upsilon}(3S) {yields} {pi}{sup +}{pi}{sup -}h{sub b}(1P)] < 1.2 x 10{sup -4}, at 90% confidence level. We also investigate the {chi}{sub bJ}(2P) {yields} {pi}{sup +}{pi}{sup -} {chi}{sub bJ}(1P), {Upsilon}(3S) {yields} {pi}{sup +}{pi}{sup -}{Upsilon}(2S), and {Upsilon}(2S) {yields} {pi}{sup +}{pi}{sup -}{Upsilon}(1S) di-pion transitions and present an improved measurement of the branching fraction of the {Upsilon}(3S) {yields} {pi}{sup +}{pi}{sup -}{Upsilon}(2S) decay and of the {Upsilon}(3S) - {Upsilon}(2S) mass difference.
Date: December 9, 2011
Creator: Lees, J.P.; Poireau, V.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E. et al.
Partner: UNT Libraries Government Documents Department

Cold Nuclear Matter Effects on J/psi and Upsilon Production at the LHC

Description: The charmonium yields are expected to be considerably suppressed if a deconfined medium is formed in high-energy heavy-ion collisions. In addition, the bottomonium states, with the possible exception of the {Upsilon}(1S) state, are also expected to be suppressed in heavy-ion collisions. However, in proton-nucleus collisions the quarkonium production cross sections, even those of the {Upsilon}(1S), scale less than linearly with the number of binary nucleon-nucleon collisions. These 'cold nuclear matter' effects need to be accounted for before signals of the high density QCD medium can be identified in the measurements made in nucleus-nucleus collisions. We identify two cold nuclear matter effects important for midrapidity quarkonium production: 'nuclear absorption', typically characterized as a final-state effect on the produced quarkonium state and shadowing, the modification of the parton densities in nuclei relative to the nucleon, an initial-state effect. We characterize these effects and study their energy and rapidity dependence.
Date: June 23, 2009
Creator: Vogt, R
Partner: UNT Libraries Government Documents Department

Lattice calculation of quarkonium decay matrix elements

Description: The authors calculate the NRQCD (nonrelativistic QCD) matrix elements for the decays of the lowest-lying S- and P-wave states of charmonium and bottomonium in quenched lattice QCD. They also compute the one-loop relations between the lattice and continuum matrix elements.
Date: September 1996
Creator: Bodwin, G. T.; Sinclair, D. K. & Kim, S.
Partner: UNT Libraries Government Documents Department

Decay rates of various bottomonium systems

Description: Using the Bodwin-Braaten-Lepage factorization theorem in heavy quarkonium decay and production processes, the authors calculated matrix elements associated with S- and P-wave bottomonium decays via lattice QCD simulation methods. In this work, they report preliminary results on the operator matching between the lattice expression and the continuum expression at one loop level. Phenomenological implications are discussed using these preliminary {ovr MS} matrix elements.
Date: December 31, 1995
Creator: Kim, S.
Partner: UNT Libraries Government Documents Department

γ Production at CDF

Description: We report on preliminary measurements of the {gamma}(1S), {gamma}(2S) and {gamma}(3S) differential and integrated cross sections in p{bar p} at {radical}s = 1.8 TeV using a sample of 16.6 {+-} 0.6 pb{sup -1} collected by the Collider Detector at Fermilab. The three resonances were reconstructed through the decay {gamma} {yields} {mu}{sup +}{mu}{sup -} in the rapidity region {vert_bar}y{vert_bar} < 0.4. The cross section results are compared to theoretical models of direct bottomonium production.
Date: July 1, 1995
Creator: Abe, F.
Partner: UNT Libraries Government Documents Department

Bottom hadrons from lattice QCD with domain wall and NRQCD fermions

Description: Dynamical 2+1 flavor lattice QCD is used to calculate the masses of bottom hadrons, including B mesons, singly and doubly bottom baryons, and for the first time also the triply-bottom baryon Omega{sub bbb}. The domain wall action is used for the up-, down-, and strange quarks (both valence and sea), while the bottom quark is implemented with non-relativistic QCD. A calculation of the bottomonium spectrum is also presented.
Date: July 1, 2009
Creator: Stefan Meinel, William Detmold, C.-J. David Lin, Matthew Wingate
Partner: UNT Libraries Government Documents Department

Observation of the Bottomonium Ground State, eta_b, at BaBar

Description: The authors present the first observation of the bottomonium ground state {eta}{sub b}(1S) in the photon energy spectrum using a sample of (109 {+-} 1) million of {Upsilon}(3S) events recorded at the {Upsilon}(3S) energy with the BaBar detector at the PEP-II B factory at SLAC. A peak at E{sub {gamma}} = 921.2{sub -2.8}{sup +2.1}(stat) {+-} 2.4(syst) MeV observed with a significance of 10 standard deviations in the photon energy spectrum is interpreted as being due to the radiative transition {Upsilon}(3S) {yields} {gamma} {eta}{sub b}(1S). This photon energy corresponds to an {eta}{sub b}(1S) mass of 9388.9{sub -2.3}{sup +3.1}(stat) {+-} 2.7(syst) MeV/c{sup 2}. The hyperfine {Upsilon}(1S)-{eta}{sub b}(1S) mass splitting is 71.4{sub -3.1}{sup +2.3}(stat) {+-} 2.7(syst) MeV/c{sup 2}. The branching fraction for this radiative {Upsilon}(3S) decay is obtained as (4.8 {+-} 0.5(stat) {+-} 1.2(syst)) x 10{sup -4}.
Date: September 9, 2008
Creator: Grenier, Philippe & Collaboration, for the BABAR
Partner: UNT Libraries Government Documents Department

Quarkonium Spectroscopy and New States from BaBar

Description: We review results on charmonium and bottomonium spectroscopy by the BaBar experiment at the PEP-II e{sup +}e{sup -} collider at SLAC. More space is reserved to the new results like the observation of hadronic non-B{bar B} {Upsilon}(4S) decays and the investigation on the production and decay properties of the recently discovered charmonium-like states X(3872) and Y (4260). These results are preliminary, unless otherwise specified.
Date: June 8, 2007
Creator: Vitale, L. & /Trieste U. /INFN, Trieste
Partner: UNT Libraries Government Documents Department

Observation of the Upsilon(13DJ ) Bottomonium State through Decays to pi+pi-Upsilon(1S)

Description: Based on 122X10{sup 6} {upsilon}(3S) events collected with the BABAR detector, we have observed the {upsilon}(1{sup 3}D{sub J}) bottomonium state through the {upsilon}(3S){yields}{gamma}{gamma}{upsilon}(1{sup 3}D{sub J}){yields}{gamma}{gamma}{pi}{sub +}{pi}{sub -}{upsilon}(1S) decay chain. The significance is 6.2 standard deviations including systematic uncertainties. The mass of the J = 2 member of the {upsilon}(1{sup 3}D{sub J}) triplet is determined to be 10164.5{-+}0.8 (stat.) {-+} 0.5 (syst.) MeV/c{sup 2}. We use the {pi}{sup +}{pi}{sup -} invariant mass and decay angular distributions to confirm the consistency of the observed state with the orbital angular momentum and parity assignments of the {upsilon}(1{sup 3}D{sub J}).
Date: June 2, 2010
Creator: del Amo Sanchez, P.; Lees, J.P.; Poireau, V.; Prencipe, E.; Tisserand, V.; /Annecy, LAPP et al.
Partner: UNT Libraries Government Documents Department