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CP Violation and mixing of B mesons at CDF

Description: We report recent studies of CP-violation and mixing in neutral B mesons from the CDF experiment at the Fermilab Tevatron Collider. Results of a direct measurement of the CP-violation parameter sin 2{beta} using B{sup 0} {yields} J/{psi}K{sub S}{sup 0} with multi flavor tagging algorithms, a search for B{sub s}{sup 0} - {bar B}{sub s}{sup 0} mixing using semileptonic decays, and the updated precision measurements of the B{sup 0} - {bar B}{sup 0} mixing parameter will be presented. The prospects for B physics with the upgraded CDF detector in the next Tevatron Collider run will also be discussed.
Date: December 13, 1999
Creator: Miao, Ting
Partner: UNT Libraries Government Documents Department

B physics at CDF

Description: Results on B physics and heavy quarkonia production based on data collected during the Tevatron run Ia and Ib are presented. For B physics, results on B meson man measurement, B meson lifetimes, rare decay searches, B{sup o} {bar B} {sup o} mixing and B meson polarization are discussed. Accuracies comparable to those of leading e{sup +} e{sup {minus}} experiments are attained or expected to be attained by the end of Tevatron Run I in almost all these fields. features of J/{psi}, {psi}((2S), {chi}c, and {Upsilon} bound state production are also discussed.
Date: December 31, 1995
Creator: Meschi, E.
Partner: UNT Libraries Government Documents Department

B lifetimes and mixing with the SLD

Description: The lifetimes of B{sup 0} and B{sup {plus_minus}} mesons have been measured with the SLD detector at the SLC using topological reconstructions of the B mesons. Studies of B{sub s} mixing, using similar techniques, show that the prospects for measuring B{sub s} mixing with an upgraded vertex detector are good if x{sub x} {le} 15.
Date: December 1, 1995
Partner: UNT Libraries Government Documents Department

CP violation, mixing and rare decays at the Tevatron now and in Run II

Description: We review the status of current B mixing and CP violation measurements from the Fermilab Tevatron. With the existing data sample, the CDF collaboration has made competitive measurements of B{sub d}{sup 0} mixing; set limits on B{sub s}{sup 0} mixing and has begun a direct search of CP violation in the B system through the decay B{sup 0}/{anti B}{sup 0}{yields}J/{psi}K{sub S}{sup 0}. The prospects for future b measurements at the Tevatron, including CP violation, B{sub s}{sup 0} mixing and rare decay searches are discussed.
Date: December 1, 1998
Creator: Pitts, Kevin T.
Partner: UNT Libraries Government Documents Department

CP violation

Description: In this talk the author briefly reviews the cosmological importance of CP violation and the status of calculations of baryogenisis in the context of the Standard Model. The author then turns to a discussion of Standard Model Predictions for CP violation in B decays, stressing the importance of multiple measurements to overconstrain the model parameters and thus search for indications of beyond-Standard-Model physics.
Date: December 1, 1995
Creator: Quinn, H.
Partner: UNT Libraries Government Documents Department

Support of experimental high energy physics research at the University of South Carolina. Final technical report, 1980--1992

Description: Twelve years of support by the US Department of Energy have turned a two man team with no equipment and no graduate students working on a single experiment into an active group of four professors, one post-doctoral research associate and three graduate students working with appropriate equipment on three major experiments and several other projects. 162 references.
Date: December 31, 1992
Creator: Childers, R.L.; Darden, C.W.; Rosenfeld, C. & Wilson, J.R.
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

[Elementary particle physics. Annual report]

Description: The BABAR construction phase is ending and first data is expected during May, 1999. During construction, UTD has developed analysis framework software, contributed to the BABAR Physics Book, assembled a first rate computing facility, and pioneered Internet-based video techniques for the collaboration. The authors are now defining the physics goals, and are participating in the formation physics analysis groups. They are starting to use their computing facility for BABAR production jobs.
Date: December 31, 1998
Creator: Izen, J.M. & Lou, X.
Partner: UNT Libraries Government Documents Department

CP violation in K decays and rare decays

Description: The present status of CP violation in decays of neutral kaons is reviewed. In addition selected rare decays of both K and B mesons are discussed. The emphasis is in particular on observables that can be reliably calculated and thus offer the possibility of clean tests of standard model flavor physics. 105 refs.
Date: December 1, 1996
Creator: Buchalla, G.
Partner: UNT Libraries Government Documents Department

Prospects for mixing and CP violation at the Tevatron

Description: The Fermilab p{bar p} Tevatron collider, operating at {radical}s = 1. 8 TeV, is a proficient source of B hadrons. The first collider run, Run I, has clearly proven that B states can be observed cleanly and can be studied in great detail in a hadron collider environment. In this presentation the future of the study of B{bar B} mixing and of CP violation at the Tevatron, with an upgraded machine and detectors, is discussed.
Date: December 1, 1996
Creator: Rijssenbeek, M. & collaborations, The CDF and DO
Partner: UNT Libraries Government Documents Department

Studies of high energy phenomena using muons. Final report

Description: This report covers the activities of the NIU high energy physics group as supported by DOE contract DE-FG02-91ER40641.A000 during the period from 1992 to 1995, and is the final report for this award. The group had three main efforts. The first was the D0 experiment at the Fermilab proton-antiproton collider, with major emphasis on its muon system. The second is the involvement of a portion of the group in Fermilab Experiment 789. Finally, the authors were members of the SDC collaboration at the SSC. The group consisted of four faculty members, three research associates, and undergraduate and graduate students. The D0 experiment at Fermilab is one of two (the other is CDF) general purpose experiments operating at the Tevatron proton-antiproton collider. Starting in the Fall of 1992, the first data collection occurred at D0. Physics publications are tabulated in the Appendix, with the discovery of the top quark in 1995 being the most prominent. Members of the NIU group worked on a variety of physics topics: Hedin on B-physics and the top-quark search, Fortner on Drell-Yan and other QCD topics, Green on di-Boson production, and Markeloff on excited-quark states. Hedin was also co-coordinator of the B-physics group during this period. The primary emphasis of the NIU D0 group was the muon system. NIU had particular responsibilities for data acquisition; chamber calibration; the Level-2 trigger; and the reconstruction. Hedin also was coordinator of muon software and had the responsibility for muon identification. Work on these items is summarized in a series of D0 Notes listed in the Appendix. Willis, Sirotenko, Hedin and Fortener were also members of the SDC collaboration at the SSC. NIU was a key participant in the calculation of low-energy neutron and photon backgrounds in the SDC experiment, and in designing shielding for the proposed muon system.
Date: December 31, 1995
Partner: UNT Libraries Government Documents Department

Phenomenological study of strong decays of heavy hadrons in heavy quark effective theory

Description: The application of the tensor formalism of the heavy quark effective theory (HQET) at leading order to strong decays of heavy hadrons is presented. Comparisons between experimental and theoretical predictions of ratios of decay rated for B mesons, D mesons and kaons are given. The application of HQET to strange mesons presents some encouraging results. The spin-flavor symmetry is used to predict some decay rates that have not yet been measured.
Date: December 1999
Creator: Tregoures, N. & Roberts, W.
Partner: UNT Libraries Government Documents Department

Enhanced CP violation with B {r_arrow} KD{sup 0} ({anti D}{sup 0}) modes and extraction of the CKM angle {gamma}

Description: The Gronau-London-Wyler (GLW) method extracts the CKM angle {gamma} by measuring B{sup {+-}} decay rates involving D{sup 0}/{anti D}{sup 0} mesons. Since that method necessitates the interference between two amplitudes that are significantly different in magnitude, the resulting asymmetries tend to be small. CP violation can be greatly enhanced for decays to final states that are common to both D{sup 0} and {anti D}{sup 0} and that are not CP eigenstates. In particular, large asymmetries are possible for final states f such that D{sup 0} {r_arrow} f is doubly Cabibbo suppressed while {anti D}{sup 0} {r_arrow} f is Cabibbo allowed. The measurement of interference effects in two such modes allows the extraction of {gamma} without prior knowledge of Br(B{sup {minus}} {r_arrow} K{sup {minus}} {anti D}{sup 0}), which may be difficult to determine due to backgrounds.
Date: December 1, 1996
Creator: Atwood, David; Dunietz, Isard & Soni, Amarjit
Partner: UNT Libraries Government Documents Department

Exact heavy to light meson form factors in the combined heavy quark, large N{sub c} and chiral limits

Description: We demonstrate that the form factors of local operators between a heavy meson state (like the B) and a light pseudoscalar state (like the pion) are given exactly by a single pole form in the combined heavy quark, large N{sub c} (number of colors) and chiral limits. We discuss the deviations from this exact result from finite heavy quark masses, non-zero light quark masses and finite N{sub c}. We comment on some of the numerous implications of this result.
Date: December 1, 1993
Creator: Grinstein, B. & Mende, P.
Partner: UNT Libraries Government Documents Department

Lattice QCD and the unitarity triangle

Description: Theoretical and computational advances in lattice calculations are reviewed, with focus on examples relevant to the unitarity triangle of the CKM matrix. Recent progress in semi-leptonic form factors for B {yields} {pi}/v and B {yields} D*lv, as well as the parameter {zeta} in B{sup 0}-{bar B}{sup 0} mixing, are highlighted.
Date: December 3, 2001
Creator: Kronfeld, Andreas S
Partner: UNT Libraries Government Documents Department

Heavy quark production at CDF

Description: Heavy quark production cross-sections, correlations and polarizations have been measured at the Collider Detector at Fermilab (CDF) using 118 pb{sup -1} of data collected from the 1992 to 1995 Run I of the Fermilab Tevatron. There is still disagreement between theoretical predictions of bottom and charm hadro-production cross-sections and the Run I results. The observed transverse momentum spectrum of the prompt J/{psi} production polarization is still not understood. Run II of the Tevatron began in July of 2001 and the CDF Run II detector [11] has collected 70 pb{sup -1} of physics quality data since January 2002. Large statistics of onia states have been collected. Exclusive B meson decay modes have been reconstructed and the SVT level 2 displaced track trigger has produced large samples of D mesons. The prompt charm and b {yields} cX fractions in both charmonium and D meson samples have been measured. Run II is now poised to greatly enhance the knowledge of heavy quark production dynamics well beyond the reach of the Run I detector.
Date: December 13, 2002
Creator: Bishai, M.
Partner: UNT Libraries Government Documents Department

Overview of the BTeV Pixel Detector

Description: BTeV is a new Fermilab beauty and charm experiment designed to operate in the CZero region of the Tevatron collider. Critical to the success of BTeV is its pixel detector. The unique features of this pixel detector include its proximity to the beam, its operation with a beam crossing time of 132 ns, and the need for the detector information to be read out quickly enough to be used for the lowest level trigger. This talk presents an overview of the pixel detector design, giving the motivations for the technical choices made. The status of the current R&D on detector components is also reviewed. Additional Pixel 2002 talks on the BTeV pixel detector are given by Dave Christian[1], Mayling Wong[2], and Sergio Zimmermann[3]. Table 1 gives a selection of pixel detector parameters for the ALICE, ATLAS, BTeV, and CMS experiments. Comparing the progression of this table, which I have been updating for the last several years, has shown a convergence of specifications. Nevertheless, significant differences endure. The BTeV data-driven readout, horizontal and vertical position resolution better than 9 {micro}m with the {+-} 300 mr forward acceptance, and positioning in vacuum and as close as 6 mm from the circulating beams remain unique. These features are driven by the physics goals of the BTeV experiment. Table 2 demonstrates that the vertex trigger performance made possible by these features is requisite for a very large fraction of the B meson decay physics which is so central to the motivation for BTeV. For most of the physics quantities of interest listed in the table, the vertex trigger is essential. The performance of the BTeV pixel detector may be summarized by looking at particular physics examples; e.g., the B{sub s} meson decay B{sub s} {yields} D{sub s}{sup -} K{sup +}. For that decay, studies ...
Date: December 10, 2002
Creator: Appel, Jeffrey A
Partner: UNT Libraries Government Documents Department

The BaBar cesium iodide electromagnetic calorimeter

Description: The BABAR Cesium Iodide Electromagnetic Calorimeter is currently in the technical design stage. The calorimeter consists of approximately 10,000 individual thallium-doped cesium iodide crystals arranged in a near-hermetic barrel and endcap structure. Taking previous cesium iodide calorimeters as a benchmark, we hope to build a system with roughly two times better energy resolution. This will be achieved by a combination of high quality crystal growing, precision mechanical processing of crystals and support structure, highly efficient light collection and low noise readout electronics. The calorimeter described here represents the current state of the design and we are undertaking an active period of optimization before this design is finalized. We discuss here the physics motivation, the current design and options for optimization.
Date: December 1, 1994
Creator: Wuest, C.R.
Partner: UNT Libraries Government Documents Department

Problems at the interface between heavy flavor physics, QCD and hadron spectroscopy.

Description: The following subjects are discussed in this report: (1) Pentaquark--why it is important and how new technologies (vertex detectors) suggest drastically different approaches form the search used by Ashery et al.; (2) problems in B decays with implications for heavy quark decays to excited light quark states like the Al; (3) problems in B and D decays to final states including {eta} and {eta}{prime} indicating that standard quark mixing might not hold; (4) possible contributions of hybrid quarkonium states to B decays; (5) heavy flavor decays to {omega}{tau} which disagree with conventional expectations; and (6) possible new spin effects in {Lambda}{sub b} decay and the effect on the lifetime difference between the {Lambda}{sub b} and B mesons.
Date: December 12, 1997
Creator: Lipkin, H. J.
Partner: UNT Libraries Government Documents Department

B and D meson decay constants from 2+1 flavor improved staggered simulations

Description: We give an update on simulation results for the decay constants f{sub B}; f{sub B{sub s}}, f{sub D} and f{sub D{sub s}}. These decay constants are important for precision tests of the standard model, in particular entering as inputs to the global CKM unitarity triangle fit. The results presented here make use of the MILC (2+1)-flavor asqtad ensembles, with heavy quarks incorporated using the clover action with the Fermilab method. Partially quenched, staggered chiral perturbation theory is used to extract the decay constants at the physical point. In addition, we give error projections for a new analysis in progress, based on an extended data set.
Date: December 1, 2011
Creator: Neil, E.T.; Bailey, Jon A.; Bazavov, A.; Bernard, C.; Bouchard, C.M.; DeTar, C. et al.
Partner: UNT Libraries Government Documents Department

Observation of the Rare Decay B+ \to K+pi0pi0 and Measurement of the Quasi-two Body Contributions B+ \to K*(892)+pi0, B+ \to f0(980)K+ and B+ \to chic0K+

Description: We report an analysis of charmless hadronic decays of charged B mesons to the final state K{sup +}{pi}{sup 0}{pi}{sup 0}, using a data sample of (470.9 {+-} 2.8) x 10{sup 6} B{bar B} events collected with the BABAR detector at the {Gamma}(4S) resonance. We observe an excess of signal events, with a significance above 10 standard deviations including systematic uncertainties, and measure the branching fraction and CP asymmetry to be {Beta}(B{sup +} {yields} K{sup +}{pi}{sup 0}{pi}{sup 0}) = (16.2 {+-} 1.2 {+-} 1.5) x 10{sup -6} and A{sub CP}(B{sup +} {yields} K{sup +}{pi}{sup 0}{pi}{sup 0}) = -0.06 {+-} 0.06 {+-} 0.04, where the uncertainties are statistical and systematic, respectively. Additionally, we study the contributions of the B{sup +} {yields} K{sup +}(892){sup +}{pi}{sup 0}, B{sup +} {yields} f{sub 0}(980)K{sup +}, and B{sup +} {yields} {chi}{sub c0}K{sup +} quasi-two-body decays. We report the world's best measurements of the branching fraction and CP asymmetry of the B{sup +} {yields} K{sup +}{pi}{sup 0}{pi}{sup 0} and B{sup +} {yields} K{sup +}(892){sup +}{pi}{sup 0} channels.
Date: December 13, 2011
Creator: Lees, J.P.; Poireau, V.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E. et al.
Partner: UNT Libraries Government Documents Department

Study of B to pi l nu and B to rho l nu Decays and Determination of |V_ub|

Description: We present an analysis of exclusive charmless semileptonic B-meson decays based on 377 million B{bar B} pairs recorded with the BABAR detector at the {Upsilon} (4S) resonance. We select four event samples corresponding to the decay modes B{sup 0} {yields} {pi}{sup -}{ell}{sup +}{nu}, B{sup +} {yields} {pi}{sup 0}{ell}{sup +}{nu}, B{sup 0} {yields} {rho}{sup -}{ell}{sup +}{nu}, and B{sup +} {yields} {rho}{sup 0}{ell}{sup +}{nu}, and find the measured branching fractions to be consistent with isospin symmetry. Assuming isospin symmetry, we combine the two B {yields} {pi}{ell}{nu} samples, and similarly the two B {yields} {rho}{ell}{nu} samples, and measure the branching fractions {Beta}(B{sup 0} {yields} {pi}{sup -}{ell}{sup +}{nu}) = (1.41 {+-} 0.05 {+-} 0.07) x 10{sup -4} and {Beta}(B{sup 0} {yields} {rho}{sup 0}{ell}{sup +}{nu}) = (1.75 {+-} 0.15 {+-} 0.27) x 10{sup -4}, where the errors are statistical and systematic. We compare the measured distribution in q{sup 2}, the momentum transfer squared, with predictions for the form factors from QCD calculations and determine the CKM matrix element |V{sub ub}|. Based on the measured partial branching fraction for B {yields} {pi}{ell}{nu} in the range q{sup 2} < 12 GeV{sup 2} and the most recent LCSR calculations we obtain |V{sub ub}| = (3.78 {+-} 0.13{sub -0.40}{sup +0.55}) x 10{sup -3}, where the errors refer to the experimental and theoretical uncertainties. From a simultaneous fit to the data over the full q{sup 2} range and the FNAL/MILC lattice QCD results, we obtain |V{sub ub}| = (2.95 {+-} 0.31) x 10{sup -3} from B {yields} {pi}{ell}{nu}, where the error is the combined experimental and theoretical uncertainty.
Date: December 9, 2011
Creator: del Amo Sanchez, P.; Lees, J.P.; Poireau, V.; Prencipe, E.; Tisserand, V.; /Annecy, LAPP et al.
Partner: UNT Libraries Government Documents Department

Charmless and Penguin Decays at CDF

Description: Penguin transitions play a key role in the search of New Physics hints in the heavy flavor sector. During the last decade CDF has been exploring this opportunity with a rich study of two-body charmless decays of neutral B mesons into charged final-state particles. After briefly introducing the aspects of this physics peculiar to the hadron collision environment, I report on two interesting results: the first polarization measurement of the B{sub s}{sup 0} {yields} {phi}{phi} decay and the update of the B{sub (s)}{sup 0} {yields} h{sup +}h{prime}{sup -} decays analysis.
Date: December 1, 2010
Creator: Dorigo, Mirco & Collaboration, for the CDF
Partner: UNT Libraries Government Documents Department