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

Description: We report on the measurement of inclusive muon and b quark production by the D0 collaboration in p{bar p} collisions at {radical}s = 1.8 TeV at the Fermilab Tevatron Collider. The results represent a refined analysis of the previously published 1992--93 data. We measure the muon cross section due to b quark decays over the kinematic range 4 < p{sub T}{sup {mu}} < 30 GeV/c and {vert_bar}y{sup {mu}}{vert_bar} < 0.8. The extracted b quark production cross section is consistent with next to leading order QCD predictions within theoretical and experimental errors. The improved inclusive b quark production cross section is 6.9 {plus_minus}0.1(stat) {plus_minus} 2.2(syst) {mu}b for p{sub T}{sup {mu}} > 6 GeV/c and {vert_bar}y{sup b}{vert_bar} < 1.0.
Date: July 1, 1995
Creator: Abachi, S.
Partner: UNT Libraries Government Documents Department

J/{psi} production in p{anti p} collisions at {radical}s = 1.8 TeV

Description: The authors have studied J/{psi} production in p{anti p} collisions at {radical}s = 1.8 TeV with the D0 detector at Fermilab, using a {mu}{sup +}{mu}{sup {minus}} data sample corresponding to an integrated luminosity of 13 pb{sup {minus}1}. They have measured the inclusive J/{psi} production cross section as a function of J/{psi} transverse momentum p{sub T}. For the kinematic range p{sub T} > 8 GeV/c and {vert_bar}{eta}{vert_bar} < 0.6 they obtain Br(J/{psi} {yields} {mu}{sup +}{mu}{sup {minus}}) {center_dot} {sigma}(p{anti p} {yields} J/{psi} + X) = 1.93 {+-} 0.16(stat) {+-} 0.43(syst) nb. Using the muon impact parameter they have estimated the fraction of J/{psi} mesons coming from B meson decays to be f{sub b} = 0.35 {+-} 0.09 (stat) {+-} 0.10 (syst) and inferred the inclusive b production cross section. From the information on the event topology a fraction of non-isolated J/{psi} events has been measured to be f{sub non-isol} = 0.64 {+-} 0.09(stat) {+-} 0.06(syst). They have also obtained the fraction of events resulting from radiative decays of {chi}{sub c} states as f{sub {chi}} = 0.30 {+-} 0.07(stat) {+-} 0.07(syst). They discuss the implications of the measurements for charmonium production processes.
Date: July 1, 1995
Creator: Abachi, S.
Partner: UNT Libraries Government Documents Department

Rapidity dependence of the inclusive J/{Psi} production in p{bar p} collisions at {radical}s = 1.8 TeV

Description: We have studied J/{psi} production in p{bar p} collisions at {radical}s = 1.8 TeV with the D0 detector at Fermilab, using a {mu}{sup +}{mu}{sup {minus}} data sample collected during the 1994--1995 collider run. We have measured the inclusive J/{psi} production cross section as a function of the J/{psi} transverse momentum, p{sub T}{sup J/{psi}}, in the central and forward rapidity regions. The cross section d{sigma}/dp{sub T}{sup J/{psi}} for {vert_bar}{eta}{sup J/{psi}}{vert_bar}<0.6 covers the p{sub T}{sup J/{psi}} range from 8 to 20 GeV/c. The new measurements are in a good agreement with the CDF and earlier D0 results. The cross section d{sigma}/dp{sub T}{sup J/{psi}} for 2.6 <{vert_bar}{eta}{sup J/{psi}}{vert_bar}<3.4 covers the p{sub T}{sup J/{psi}} range from 3 to 12 GeV/c. We combine the measurements in the two {vert_bar}{eta}{sup J/{psi}}{vert_bar} regions to calculate d{sigma}/d{eta}{sup J/{psi}} for p{sub T}{sup J/{psi}} > 8 GeV/c. The data are compared with the next-to-leading (NLO) QCD calculations, which take into account different J/{psi} production mechanisms.
Date: November 1, 1995
Creator: Abachi, S.
Partner: UNT Libraries Government Documents Department

J/{psi} and {psi}{prime} production at CDF

Description: This paper presents measurements of the J/{psi} and {psi}{prime} production cross sections in p{ovr p} collisions at {radical}s = 1.8 TeV. The cross sections are measured in the kinematic region P{sub T} {gt} 5 GeV/c, {vert_bar}{eta}{vert_bar} {lt} 0.6 using the dimuon decay channel. The fraction of events from B decays is measured and used to calculate the J/{psi} and {psi}{prime} cross sections from B decay. The fraction of J/{psi} events from {chi}{sub c} decays is also measured and used to calculate the J/{psi} cross section from direct production. 11 refs., 5 figs., 1 tab.
Date: July 1, 1996
Creator: Abe, F.
Partner: UNT Libraries Government Documents Department

A limit on {sigma} {center_dot} BR (B{sub c}{sup {+-}} {yields} J/{psi} + {pi}{sup {+-}})/{sigma} {center_dot} BR(B{sub u}{sup {+-}} {yields} J/{psi} + K{sup {+-}}) in {radical}s = 1.8 TeV proton-antiproton collisions

Description: We report on the results of a search for the B{sub c} (b{bar c}) meson in the decay B{sub c}{sup +-} {yields} J/{psi} + {pi}{sup +-}. This search is guided by a control sample of decays of B{sub u} mesons to J/{psi} + K and uses {approx_equal} 75pb{sup -1} of data collected at the Collider Detector Facility (CDF) at Fermilab. The lifetime of the B{sub c} meson is unknown, so the 95% confidence level limit on {sigma} {center_dot} BR(B{sub c} {yields} {psi} + {pi})/{sigma} {center_dot} BR(B{sub u} {yields} {psi} + K) is obtained as a function of the B{sub c} lifetime.
Date: July 15, 1995
Creator: Abe, F.
Partner: UNT Libraries Government Documents Department

Measurement of the B{sup +} and B{sup 0} meson lifetimes using exclusive B {yields} {psi}K decays at CDF

Description: The authors present recent CDF measurements of {tau}{sup +}, {tau}{sup 0}, and {tau}{sup +}/{tau}{sup 0} using exclusive B {yields} {psi}K decays, where B = B{sup +} or B{sup 0}, {psi} = J/{psi} or {psi}(2S), and K = K{sup +}, K*(892){sup 0}, K{sub S}{sup 0}, or K*(892){sup +}. The precision of these results is less than 10% and is nearly identical to that previously reported at LEP.
Date: July 1995
Creator: Abe, F.
Partner: UNT Libraries Government Documents Department

Measurement of the polarization in the decays B{sup 0} {yields} J/{psi}K*{sup 0} and B{sub s}{sup 0} {yields} J/{psi}{phi}

Description: The authors report on a measurement of the longitudinal polarization fraction in the decay B{sup 0} {yields} J/{psi}K*{sup 0} using data collected with the Collider Detector at Fermilab. B{sup 0} mesons are 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}}. A sample of 65 {+-} 10 events is used to obtain the result {Lambda}{sub L}/{Lambda} = 0.65 {+-} 0.10 (stat) {+-} 0.04 (sys). The first measurement of {Lambda}{sub L}/{Lambda} in the decay B{sub s}{sup 0} {yields} J/{psi}{phi} is also presented.
Date: July 1995
Creator: Abe, F.
Partner: UNT Libraries Government Documents Department

Observation of B{sup +} {yields} J/{psi}{pi}{sup +}

Description: We report on the observation of the Cabibbo-suppresed mode B{sup +} J/{psi}{pi}{sup +}, with J/{psi} {yields} {mu}{sup +}{mu}{sup {minus}}. Further, we calculate the relative branching ratio. BR(B{sup +} - J/{psi}{pi}{sup +})/BR(B{sup +} {yields} J/{psi}K{sup +}) and find a value of (4.9{sub {minus}1.7}{sup +}{plus_minus}1.1)%.
Date: July 1, 1995
Creator: Abe, F.
Partner: UNT Libraries Government Documents Department

Production of J/{Psi} from {chi}{sub c} decays at CDF

Description: We have measured the fraction of J/{psi} originating from {chi}{sub c} states in p{bar p} collisions at {radical}s = 1.8 TeV in four bins of J/{psi} P{sub T}. The fraction in the inclusive CDF J/{psi} sample with P{sub T}{sup J/{psi}} > 4.0 GeV/c and {vert_bar}{eta}{sup J/{psi}}{vert_bar} < 0.6 is f{sub x}{sup J/{psi}} = 28.3{+-}1.6(stat){+-}6.8(syst)%. The fraction of J/{psi} from {chi}{sub c} not including contributions from B{yields}J/{psi}. X and B {yields} {chi}{sub c} X is f(Nob){chi}{sup J/{psi}} = 32.3{+-}2.0(stat){+-}8.5(syst)%. We have also found that directly produced {chi}{sub c}`s are produced in the ratio = {sigma}({chi}{sub c2}) over {sigma}({chi}{sub cl}) + {sigma}({chi}{sub c2})= 0.47{+-}0.08(stat){+-}0.02(syst.)
Date: July 1, 1995
Creator: Abe, F.
Partner: UNT Libraries Government Documents Department

Heavy flavor production in fixed-target experiments

Description: This presentation is a review of recent measurements on charm production at fixed-target experiments. The measurements are relevant to a number of basic physics issues: tests of perturbative QCD, fragmentation, and basic hadronic structure. We now have high quality, high statistics data from several fixed-target experiments. These include a total of about 30,000 fully reconstructed open charm decays and even more copious J/{Psi}, {Psi}, and {Upsilon} decays. Reconstruction of the full data is now reaching completion and we await final results for systematic physics interpretations. This review of the current situation will be followed by a brief look beyond, toward beauty production at fixed-target experiments.
Date: September 1, 1990
Creator: Appel, J.A.
Partner: UNT Libraries Government Documents Department

Precision measurements of charmonium states formed in {anti p}p annihilation

Description: Fermilab experiment E-760 studies the resonant formation of Charmonium states in proton-antiproton interactions using a hydrogen gas-jet target in the antiproton Accumulator ring at Fermilab. Precision measurements of the mass and width of the Charmonium states, {chi}{sub 1}, {chi}{sub 2} and a new measurement of the {psi} mass are presented.
Date: August 1, 1991
Creator: Armstrong, T.A.; Bettoni, D. & Bharadwaj, V.
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

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

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

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

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

B-physics at CDF

Description: During the 1988/1989 run at the Fermilab Tevatron, the CDF detector collected {approx equal}4.1 pb{sup {minus}1} of p{bar p} data at {radical}s = 1.8 TeV. The main goals of this run being physics at high p{sub t}, the CDF trigger was tuned'' for maximizing signals from Z{sup 0}s, Ws, t-quarks, etc. As such, compared to the high p{sub t} physics, the b-physics program was of secondary importance other than that which would be used for background calculations. Also, CDF had no vertex chamber capability for seeing displaced vertices. However, significant b-quark, physics results are evident in two data samples; inclusive electrons and inclusive J/{psi} where J/{psi} {yields} {mu}{sup +}{mu}{sup {minus}}. We can then ask ourselves, given all this, why is it that CDF is able to do b-quark physics The answer is that nature has been kind enough to provide b-quarks at an extremely high rate at the Tevatron. The production cross-section for b{bar b} production is quite large. In the rest of this paper, I will try to specify the goals for b-physics using the inclusive electrons and J/{psi} signals for the 1988/1989 data set. I will then provide a brief look at the data, and will finish with some highly speculative guesses as to whether or not experiments at the Tevatron which look for CP violation in the b sector are possible.
Date: December 10, 1990
Creator: Baden, A.R. (Harvard Univ., Cambridge, MA (USA))
Partner: UNT Libraries Government Documents Department

Quarkonia production in p{bar p}-collisions with CDF

Description: The production cross sections for {gamma}`s, {psi}`s and {chi}{sub c}`s in high energy p{bar p} collisions have been measured using the CDF detector at Fermilab. Heavy quarkonia production involves a variety of mechanisms, and the data is used to disentangle various components. Large prompt {psi}-cross sections were observed, contrary to conventional expectations.
Date: July 1, 1995
Creator: Bauer, G.
Partner: UNT Libraries Government Documents Department

Inclusive b quark and heavy quarkonium production at DO

Description: The authors report the latest results on the measurement of inclusive b quark and heavy quarkonium production by the DO collaboration in p{anti p} collisions at {radical}s = 1.8 TeV at the Fermilab Tevatron Collider. The results are from analyses of the 1992--93 data. This report includes measurements of inclusive b quark, J/{psi} and {Upsilon} meson production cross sections. The b quark production cross section, measured in inclusive muon data, is consistent with next to leading order QCD predictions within theoretical and experimental errors. They study J/{psi} and {Upsilon} meson production in dimuon events and perform an investigation of the J/{psi} production mechanisms. Including the latest developments in charmonium phenomenology, the J/{psi} production rates are now almost all accounted for in the transverse momentum range above 8 GeV/c. The observed {Upsilon} production rates, however, are higher than expected by a factor five.
Date: July 1, 1995
Creator: Bazizi, K.A.
Partner: UNT Libraries Government Documents Department

Signatures of color-octet quarkonium production

Description: Quarkonium spectroscopy, decay and production has provided scientists with an interesting place to test their ideas on QCD ever since charmonium was discovered in 1974. Yet, the potential of perturbative QCD (PQCD) to treat production and decay has been fully exploited only recently in a development comparable to that of Heavy Quark Effective Theory for heavy-light mesons. About the same time, experiments measuring quarkonium production at large transverse momentum have confronted theorists with surprisingly large cross sections. These observations have led to the understanding that fragmentation and hadronization of color-octet quark-antiquark (Q{anti Q}) pairs are essential in the production process. Color-octet mechanisms were considered in quarkonium decays already a while ago. They were found to solve the problem of infrared divergences in P-wave decays in a systematic way. Taking them into account also in S-wave production, where they are not required by perturbative consistency in leading order of a nonrelativistic expansion, opens the promise of a quantitative description of quarkonium production. The author briefly reviews the nonrelativistic QCD picture of quarkonium production and its confrontation with experiment in various production processes.
Date: May 1, 1996
Creator: Beneke, M.
Partner: UNT Libraries Government Documents Department

Report from the polarization group of the Fermilab injector workshop

Description: The group considered physics, accelerator, and polarized source issues. Most of the physics study was concerned with what significant and unique experiments could be done if polarized protons could be accelerated in the main injector and eventually in the Tevatron. 12 refs., 4 figs.
Date: July 20, 1989
Creator: Berger, E.; Glass, G.; Imai, K.; Jones, L.; Lin, A.M.T.; Mane, S.R. et al.
Partner: UNT Libraries Government Documents Department

Partial wave analysis of the K sup + K sup 0. pi. sup minus system produced in the reaction. pi. sup minus p yields K sup + K sup 0. pi. sup minus n at 8 GeV/c

Description: We have performed a partial wave analysis of the K{sup +}K{sub S}{sup 0}{pi}{sup {minus}} system produced in the reaction {pi}{sup {minus}}p {yields} K{sup +}{bar K}{sup 0}{pi}{sup {minus}}n at 8 GeV/c. We present the results of the analysis of 30,740 events in the mass range 1.24--1.60 GeV/c{sup 2}, with 0.0 {le} {minus}t < 1. 0 GeV{sup 2}/c{sup 2}. In the 1.28 GeV/c{sup 2} mass region, we see evidence for a J{sup PG} = 0{sup {minus plus}} resonance in addition to the resonant 1{sup 2+} wave. We observe a 0{sup {minus plus}} resonance and possibly a small 1{sup 2+} resonance in the 1.42 GeV/c{sup 2} region. We also observe a 1{sup 2+} state near 1.5 GeV/c{sup 2}. 8 refs., 5 figs.
Date: January 1, 1988
Creator: Blessing, S.; Crittenden, R.; Dzierba, A.; Marshall, T.; Teige, S.; Zieminska, D. et al.
Partner: UNT Libraries Government Documents Department

Measurement of sin2{beta} from J/{psi} K{sub s} decays

Description: The CP-violating parameter sin 2{beta} is directly measured using 110 pb{sup {minus}1} of data accumulated with the CDF detector at the Fermilab {anti p}p Tevatron collider operating at {radical}s = 1.8 TeV. The signal consists of 395 {+-} 31 B{sub d}{sup 0} {r{underscore}arrow} J/{psi} K{sub s} events. Three tagging methods are used to identify the type of B meson at production (B{sub d}{sup 0} or {anti B}{sub d}{sup 0}). From the CP asymmetry, sin 2{beta} is measured to be 0.79 {sub {minus}0.44}{sup +0.41}, consistent with Standard Model predictions. Sin 2{beta} is in the interval 0 {lt} sin2{beta} {lt} 1 at the 93% confidence level.
Date: January 24, 2000
Creator: Blocker, C.A.
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