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Hadronic production of S-wave and P-wave charmed beauty mesons via heavy quark fragmentation

Description: At hadron colliders the dominant production mechanism of ({bar b}c) mesons with large transverse momentum is due to parton fragmentation. The authors compute in a model-independent way the production rates and transverse momentum spectra for S-wave and P-wave ({bar b}c) mesons at the Tevatron via the direct fragmentation of the bottom antiquark as well as the Altarelli-Parisi induced gluon fragmentation. Since all the radially and orbitally excited ({bar b}c) mesons below the BD flavor threshold will cascade into the pseudoscalar ground state B{sub c} through electromagnetic and/or hadronic transitions, they all contribute to the inclusive production of B{sub c}. The contributions of the excited S-wave and P-wave states to the inclusive production of B{sub c} are 58 and 23%, respectively, and hence significant.
Date: February 1, 1995
Creator: Cheung, K. & Yuan, Tzu Chiang
Partner: UNT Libraries Government Documents Department

Total cross sections of beauty and charmed mesons on protons

Description: Using a simple scaling law we predict the values of the total cross sections {sigma}(B{plus_minus}p), {sigma}B{sub d,s}{sup 0}, {sigma}({bar B}{sub d,s}{sup 0}P), {sigma}(D{sub d,s}{sup {plus_minus}}P), {sigma}(D{sup 0}p), {sigma}({bar D}{sup 0}p) from known total K{sub p} cross sections. We assume that mesons with the same light valence quark, q, and differing only by their heavy valence quark content, Q, have total cross sections on protons which scale as the inverse of the nth power of the reduced mass of the meson. We predict that {sigma}(Q{bar q})p > {sigma}({bar Q}q)p.
Date: June 1, 1991
Creator: Fridman, A. & Meshkov, S.
Partner: UNT Libraries Government Documents Department

First Flavor-Tagged Determination of Bounds on Mixing-Induced CP Violation in B^0_s --> j/psi phi Decays

Description: This Letter describes the first determination 1 of bounds on the CP-violation parameter 2{beta}{sub s} using B{sub s}{sup 0} decays in which the flavor of the bottom meson at production is identified. The result is based on approximately 2, 000 B{sub s}{sup 0} {yields} J/{psi}{phi} decays reconstructed in a 1.35 fb{sup -1} data sample collected with the CDFII detector using p{bar p} collisions produced at the Fermilab Tevatron. We report confidence regions in the two-dimensional space of 2{beta}{sub s} and the decay-width difference {Delta}{Lambda}. Assuming the standard model predictions of 2{beta}{sub s} and {Delta}{Lambda}, the probability of a deviation as large as the level of the observed data is 15%, corresponding to 1.5 Gaussian standard deviations.
Date: December 1, 2007
Creator: CDF Collaboration
Partner: UNT Libraries Government Documents Department

Measurements of Direct CP Violating Asymmetries in Charmless Decays of Strange Bottom Mesons and Bottom Baryons

Description: We report measurements of direct CP-violating asymmetries in charmless decays of neutral bottom hadrons to pairs of charged hadrons with the upgraded Collider Detector at the Fermilab Tevatron. Using a data sample corresponding to 1 fb{sup -1} of integrated luminosity, we obtain the first measurements of direct CP violation in bottom strange mesons, A{sub CP}(B{sub s}{sup 0} {yields} K{sup -}{pi}{sup +}) = +0.39 {+-} 0.15 (stat) {+-} 0.08 (syst), and botton baryons, A{sub CP}({Lambda}{sub b}{sup 0} {yields} p{pi}{sup -}) = + 0.03 {+-} 0.17 (stat) {+-} 0.05 (syst) and A{sub CP} ({Lambda}{sub b}{sup 0} {yields} pK{sup -}) = +0.37 {+-} 0.17 (stat) {+-} 0.03 (syst). In addition, they measure CP violation in B{sup 0} {yields} K{sup +}{pi}{sup -} decays with 3.5{sigma} significance, A{sub CP} (B{sup 0} {yields} K{sup +}{pi}{sup -}) = -0.086 {+-} 0.023 (stat) {+-} 0.009 (syst), in agreement with the current world average. Measurements of branching fractions of B{sub s}{sup 0} {yields} K{sup +}K{sup -} and B{sup 0} {yields} {pi}{sup +}{pi}{sup -} decays are also updated.
Date: March 1, 2011
Creator: Aaltonen, T.; Aaltonen, T.; Phys., /Helsinki Inst. of; Alvarez Gonzalez, B.; Phys., /Oviedo U. /Cantabria Inst. of; Amerio, S. et al.
Partner: UNT Libraries Government Documents Department

First Flavor-Tagged Determination of Bounds on Mixing-Induced CP Violation in B0(s) ---> J/psi phi Decays

Description: This Letter describes the first determination of bounds on the CP-violation parameter 2{beta}{sub s} using B{sub s}{sup 0} decays in which the flavor of the bottom meson at production is identified. The result is based on approximately 2,000 B{sub s}{sup 0} {yields} J/{psi}{phi} decays reconstructed in a 1.35 fb{sup -1} data sample collected with the CDFII detector using p{bar p} collisions produced at the Fermilab Tevatron. We report confidence regions in the two-dimensional space of 2{beta}{sub s} and the decay-width difference {Delta}{Lambda}. Assuming the standard model predictions of 2{beta}{sub s} and {Delta}{Lambda}, the probability of a deviation as large as the level of the observed data is 15%, corresponding to 1.5 Gaussian standard deviations.
Date: December 1, 2007
Creator: Aaltonen, T.; Phys., /Helsinki Inst. of; Adelman, J.; /Chicago U., EFI; Akimoto, T.; U., /Tsukuba et al.
Partner: UNT Libraries Government Documents Department

Evidence for B+ -> K*0bar K*+

Description: We present measurements of the branching fraction and fraction of longitudinal polarization for the decay B{sup +} {yields} {bar K}*{sup 0} K*{sup +} with a sample of 467 {+-} 5 million B{bar B} pairs collected with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} collider at the SLAC National Accelerator Laboratory. We obtain the branching fraction {Beta}(B{sup +} {yields} {bar K}*{sup 0} K*{sup +}) = (1.2 {+-} 0.5 {+-} 0.1) x 10{sup ?6} with a significance of 3.7 standard deviations including systematic uncertainties. We measure the fraction of longitudinal polarization f{sub L} = 0.75{sub -0.26}{sup +0.16} {+-} 0.03. The first error quoted is statistical and the second is systematic.
Date: June 19, 2009
Creator: Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prencipe, E. et al.
Partner: UNT Libraries Government Documents Department

Beauty for pedestrians toy models for CP violation and baryon asymmetry

Description: Why are particles different from antiparticles? C and P Violation - 1956; CP Violation - 1964. Why so little new experimental information in thirty years? Where has all the antimatter gone? Toy models are presented showing: (1) How CPT and {Delta}I = 1/2 make life difficult in kaon physics by requiring equal K{sup {plus_minus}} total widths and also equal partial widths to many exclusive channels. (2) How to understand and get around CPT restrictions. (3) How CP asymmetries can occur in exclusive partial widths and still add up to equal total widths. (4) Sakharov`s 1966 scenario for how CP Violation + proton decay can explain baryon asymmetry (5) How B physics can help.
Date: December 1, 1995
Creator: Lipkin, H.J.
Partner: UNT Libraries Government Documents Department

Latest Results on Orbitally Excited Strange Bottom Mesons with the CDF II Detector

Description: The authors present the latest results on the spectroscopy of orbitally excited strange bottom mesons from {approx} 1 fb{sup -1} of CDF data. The measurements are performed with fully reconstructed B decays collected by the CDF II detector at {radical}s = 1.96 TeV in both the di-muon and the fully hadronic trigger paths.
Date: October 1, 2006
Creator: Gorelov, Igor V. & U., /New Mexico
Partner: UNT Libraries Government Documents Department

Rare decays of heavy flavor at the Tevatron

Description: In this report the author reviews recent results in the field of rare decays at the Tevatron CDF II and D0 experiments. The presentation is focused on rare decays of charm and bottom mesons with two muons in the final state. This includes improvements over the previously available limits on the following branching ratios: {Beta}(D{sup +} {yields} {pi}{sup +}{mu}{sup +} {mu}{sup -}) < 4.7 x 10{sup -6}, {Beta}(B{sub s}{sup 0} {yields} {phi}{mu}{sup +} {mu}{sup -}) < 3.2 x 10{sup -6}, {Beta}(B{sub s}{sup 0} {yields} {mu}{sup +}{mu}{sup -}) < 1 x 10{sup -7}, and {Beta}(B{sub d}{sup 0} {yields} {mu}{sup +}{mu}{sup -}) < 3 x 10{sup -8} all at the 90% confidence level. Also reported are the first direct observation of D{sub s}{sup +} {yields} {phi}{pi}{sup +} {yields} {mu}{sup +}{mu}{sup -}{pi}{sup +} with a significance above background of over 7 standard deviations and evidence of D{sup +} {yields} {phi}{pi}{sup +} {yields} {mu}{sup +}{mu}{sup -}{pi}{sup +} with a significance of 3.1 and {Beta}(D{sup +} {yields} {phi}{pi}{sup +} {yields} {mu}{sup +}{mu}{sup -}{pi}{sup +}) = (1.75 {+-} 0.7 {+-} 0.5) x 10{sup -6}.
Date: September 1, 2006
Creator: Krutelyov, V. & /UC, Santa Barbara
Partner: UNT Libraries Government Documents Department

B Hadron properties measured in the D0 experiment

Description: The study of charm and beauty mesons and baryons provides many opportunities to not only measure and classify their spectroscopic states, but also it serves as a testing ground for aspects of flavor QCD such as heavy quark effective theory and lattice gauge calculations, that are used in precise calculations of masses, lifetimes and cross sections. The Fermilab Tevatron has provided both fixed target and proton--antiproton collider facilities that not only account for the discovery of b-quarks but also have dovetailed well with the b-factories to answer a variety of b-physics questions, some of which were not readily explored at existing e{sup +} e{sup -} and electron-positron colliders. An added feature of the hadron colliders is their large cross-section and high luminosity for production of b-quark states that compliments the high luminosities of the b-factories. We report on the observation of b-hadron states reconstructed using the D0 detector data at the Tevatron Collider. Measurements of the mass and relative rates of neutral excited B{sub d} and B{sub s} mesons, and the discovery of the {Xi}{sub b} baryon are described.
Date: December 1, 2008
Creator: Fisk, H.Eugene
Partner: UNT Libraries Government Documents Department

A relativistic chiral quark model for pseudoscalar emission from heavy mesons

Description: The amplitudes for one-pion mediated transitions between heavy meson excited states are obtained in the framework of the relativistic chiral quark model. The effective coupling constants to pions and the decay widths of excited heavy mesons with l {<=} 2 for non-radially excited, and the l=0 radially excited mesons are presented for both charmed and beauty mesons. They also discuss the allowed decays of strange excited heavy mesons by emission of a K-meson.
Date: September 1, 1998
Creator: Goity, J. L. & Roberts, W.
Partner: UNT Libraries Government Documents Department

Heavy quark fragmentation functions for D-wave quarkonium and charmed beauty mesons

Description: At the large transverse momentum region, the production of heavy-heavy bound-states such as charmonium, bottomonium, and {anti b}c mesons in high energy e{sup +}e{sup {minus}} and hadronic collisions is dominated by parton fragmentation. The authors calculate the heavy quark fragmentation functions into the D-wave quarkonium and {anti b}c mesons to leading order in the strong coupling constant and in the non-relativistic expansion. In the {anti b}c meson case, one set of its D-wave states is expected to lie below the open flavor threshold. The total fragmentation probability for a {anti b} antiquark to split into the D-wave {anti b}c mesons is about 2 {times} 10{sup {minus}5}, which implies that only 2% of the total pseudo-scalar ground state B{sub c} comes from the cascades of these orbitally excited states.
Date: September 1, 1995
Creator: Cheung, K. & Yuan, T.C.
Partner: UNT Libraries Government Documents Department

An Enquiry Concerning Charmless Semileptonic Decays of Bottom Mesons

Description: The branching fractions for the decays B {yields} P{ell}{nu}{sub {ell}}, where P are the pseudoscalar charmless mesons {pi}{sup {+-}}, {pi}{sup 0}, {eta} and {eta}{prime} and {ell} is an electron or muon, are measured with B{sup 0} and B{sup {+-}} mesons found in the recoil of a second B meson decaying as B {yields} D{ell}{nu}{sub {ell}} or B {yields} D*{ell}{nu}{sub {ell}}. The measurements are based on a data set of 348 fb{sup -1} of e{sup +}e{sup -} collisions at {radical}s = 10.58 GeV recorded with the BABAR detector. Assuming isospin symmetry, measured pionic branching fractions are combined into {Beta}(B{sup 0} {yields} {pi}{sup -}{ell}{sup +}{nu}{sub {ell}}) = (1.54 {+-} 0.17{sub (stat)} {+-} 0.09{sub (syst)}) x 10{sup -4}. First evidence of the B{sup +} {yields} {eta}{ell}{sup +}{nu}{sub {ell}} decay is seen; its branching fraction is measured to be {Beta}(B{sup +} {yields} {eta}{ell}{sup +}{nu}{sub {ell}}) = (0.64 {+-} 0.20{sub (stat)} {+-} 0.03{sub (syst)}) x 10{sup -4}. It is determined that {Beta}(B{sup +} {yields} {eta}{prime}{ell}{sup +}{nu}{sub {ell}}) < 0.47 x 10{sup -4} to 90% confidence. Partial branching fractions for the pionic decays in ranges of the momentum transfer and various published calculations of the B {yields} {pi} hadronic form factor are used to obtain values of the magnitude of the Cabibbo-Kobayashi-Maskawa matrix element V{sub ub} between 3.61 and 4.07 x 10{sup -3}.
Date: September 19, 2008
Creator: Chaisanguanthum, Kris Somboon & /SLAC, /Harvard U.
Partner: UNT Libraries Government Documents Department

Search for the B{sub c} meson in hadronic Z{sup 0} decays using the OPAL detector at LEP

Description: A search for decays of the B{sub c} meson was performed using data collected from 1990--1995 with the OPAL detector on or near the Z{sup 0} peak at LEP. The decay channels B{sub c}{sup +} {r_arrow} J/{psi}{pi}{sup +}, B{sub c}{sup +} {r_arrow} J/{psi}a{sub 1}{sup +} and B{sub c}{sup +} {r_arrow} J/{psi}{ell}{sup +}{nu} were investigated, where {ell} denotes an electron or a muon. Two candidates are observed in the mode B{sub c}{sup +} {r_arrow} J/{psi}{pi}{sup +}, with an estimated background of (0.63 {+-} 0.20) events. The weighted mean of the masses of the two candidates is (6.32 {+-} 0.06) GeV/c{sup 2}, which is consistent with the predicted mass of the B{sub c} meson. One candidate event is observed in the mode B{sub c}{sup +} {r_arrow} J/{psi}{ell}{sup +}{nu}, with an estimated background of (0.82 {+-} 0.19) events. No candidate events are observed in the B{sub c}{sup +} {r_arrow} J/{psi}a{sub 1}{sup +} decay mode, with an estimated background of (1.10 {+-} 0.22) events. Upper bounds at the 90% confidence level are set on the production rates for these processes.
Date: January 1, 1999
Creator: Herndon, M.F.
Partner: UNT Libraries Government Documents Department

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

Fundamental physics at the intensity frontier. Report of the workshop held December 2011 in Rockville, MD.

Description: Particle physics aims to understand the universe around us. The Standard Model of particle physics describes the basic structure of matter and forces, to the extent we have been able to probe thus far. However, it leaves some big questions unanswered. Some are within the Standard Model itself, such as why there are so many fundamental particles and why they have different masses. In other cases, the Standard Model simply fails to explain some phenomena, such as the observed matter-antimatter asymmetry in the universe, the existence of dark matter and dark energy, and the mechanism that reconciles gravity with quantum mechanics. These gaps lead us to conclude that the universe must contain new and unexplored elements of Nature. Most of particle and nuclear physics is directed towards discovering and understanding these new laws of physics. These questions are best pursued with a variety of approaches, rather than with a single experiment or technique. Particle physics uses three basic approaches, often characterized as exploration along the cosmic, energy, and intensity frontiers. Each employs different tools and techniques, but they ultimately address the same fundamental questions. This allows a multi-pronged approach where attacking basic questions from different angles furthers knowledge and provides deeper answers, so that the whole is more than a sum of the parts. A coherent picture or underlying theoretical model can more easily emerge, to be proven correct or not. The intensity frontier explores fundamental physics with intense sources and ultra-sensitive, sometimes massive detectors. It encompasses searches for extremely rare processes and for tiny deviations from Standard Model expectations. Intensity frontier experiments use precision measurements to probe quantum effects. They typically investigate very large energy scales, even higher than the kinematic reach of high energy particle accelerators. The science addresses basic questions, such as: Are there new sources of ...
Date: June 5, 2012
Creator: Hewett, J.L.; Weerts, H.; Brock, R.; Butler, J.N.; Casey, B.C.K.; Lu, Z.T. et al.
Partner: UNT Libraries Government Documents Department

Dynamical models of B yields. psi. /J K sub + *

Description: An issue of some interest in the general theory of CP violation on B meson decay is the relative admixture of even and odd final CP eigenstates in B {yields} {psi}/JK*{sub +}. For example, dominance of one sign of CP in this decay would increase the available modes for measuring the CP violation in the respective B meson decays in a beauty factory by a factor {approximately}2.5 and, hence, would decrease the luminosity requirements for such a factory from the CP violation perspective. Here, we therefore study this relative admixture in several dynamical models of the respective decay. We are encouraged by our findings. 12 refs., 3 figs.
Date: September 1, 1990
Creator: Ward, B.F.L. (Tennessee Univ., Knoxville, TN (USA). Dept. of Physics and Astronomy Stanford Linear Accelerator Center, Menlo Park, CA (USA) International Centre for Theoretical Physics, Trieste (Italy))
Partner: UNT Libraries Government Documents Department

[Research programs from the University of South Carolina on High Energy Physics]. Technical progress report for 1992

Description: Work on three main experiments is summarized: (1) study of charm physics in a wide-band photon beam; (2) charmless two-body decays of b-flavored mesons and baryons studied with a ring imaging Cherenkov counter; and (3) the AMY Program, which studies e{sup +}e{sup {minus}} interactions using the TRISTAN collider at KEK, with emphasis on trigger upgrades. Future work related to the existence of a 17-keV neutrino in {beta} decay and {nu}{sub {mu}}/{nu}{sub {tau}} oscillation is described.
Date: February 1, 1993
Creator: Rosenfeld, C.
Partner: UNT Libraries Government Documents Department

D0 papers on B-physics submitted to DPF '96: b-quark inclusive cross sections and b anti-b correlations using dimuons from the D0 experiment; Single muon production in the forward region at [radical]s=1. 8 TEV; Rapidity dependence of the inclusive J[psi] production in the forward region [radical]s=1. 8 TEV; A search for b [r arrow] X[mu][sup +][mu][sup [minus]] and B[sup 0] [r arrow] [mu][sup +][mu][sup [minus]] decays in p anti-p collisions at [radical]s=1. 8 TEV

Description: Paper 1: Using dimuons collected with the D0 detector during the 1993--1995 Tevatron collider run, the authors have measured the b-quark cross section and b[anti b] correlations as given by the difference in azimuthal angle between the two muons. Both measurements agree with the NLO QCD predictions within experimental and theoretical errors. (Three other papers are included in this report.)
Date: November 1, 1996
Creator: Vititoe, D.L. (Arizona Univ., Tucson, AZ (United States). Dept. of Physics); Kozelov, Alexander; Jesik, Richard & Collaboration., D0
Partner: UNT Libraries Government Documents Department

[Research programs from the University of South Carolina on High Energy Physics]. [119 Technical Progress Report]

Description: Work on three main experiments is summarized: (1) study of charm physics in a wide-band photon beam; (2) charmless two-body decays of b-flavored mesons and baryons studied with a ring imaging Cherenkov counter; and (3) the AMY Program, which studies e[sup +]e[sup [minus]] interactions using the TRISTAN collider at KEK, with emphasis on trigger upgrades. Future work related to the existence of a 17-keV neutrino in [beta] decay and [nu][sub [mu]]/[nu][sub [tau]] oscillation is described.
Date: January 1, 1993
Creator: Rosenfeld, C.
Partner: UNT Libraries Government Documents Department