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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

Recent results from Fermilab E687 on charm spectroscopy

Description: Recent analyses of charm spectroscopy from Fermilab fixed target experiment 687 are summarized. Emphasis is placed on the phenomenology of Cabibbo suppression in the meson sector. Such transitions have been observed in the semileptonic modes and hadronic modes. While the former transitions give us an opportunity to observe the weak current and the CKM matrix, a systematic comparison of the latter transitions allow us to study strong interaction effects, and possibly, light quark spectroscopy.
Date: July 1, 1997
Creator: Lebrun, P.
Partner: UNT Libraries Government Documents Department

CHARM 2010: Experiment summary and future charm facilities

Description: The CHARM 2010 meeting had over 30 presentations of experimental results, plus additional future facilities talks just before this summary talk. Since there is not enough time to even summarize all that has been shown from experiments and to recognize all the memorable plots and results - tempting as it is to reproduce the many clean signals and data vs theory figures, the quantum correlations plots, and the D-mixing plots before and after the latest CLEO-c data is added. So, this review will give only my personal observations, exposing my prejudices and my areas of ignorance, no doubt. This overview will be at a fairly high level of abstraction - no re-showing individual plots or results. I ask the forgiveness of those who will have been slighted in this way - meaning all the presents.
Date: December 1, 2010
Creator: Appel, Jeffrey A.
Partner: UNT Libraries Government Documents Department

Charmonium and charm decays from the Fermilab fixed target program

Description: Recent results on charm decay physics from the Fermilab Fixed Target program will be presented. There have been many physics results within the past year from experiments E687 and E791 and these will be highlighted. Many of these results are related to rare phenomena and searches. These will become even more interesting with the FOCUS experiment dataset of 1 million fully reconstructed charm decays. Preliminary signals from FOCUS as well as from SELEX will be presented together with prospects for the future. Preliminary results from E835 on the {eta}`{sub c} search will also be presented.
Date: May 1, 1998
Creator: Cheung, G.W.K.
Partner: UNT Libraries Government Documents Department

Nuevos aspectos en el estudio de la particula D en el experimento FOCUS de Fermilab

Description: The purpose of this work is to improve the reconstruction techniques of the decays of the particles that contain charm in the quark composition using the information of the Target Silicon Detector of the experiment E831 (FOCUS). That experiment runs during 1997 to 1998 in Fermilab National Laboratory. The objective of the experiment was improving the understanding of the particles that contain charm. Adding the Target Silicon Detector information in the reconstruction process of the primary vertex the position error. This reduction produces an improvement in the mass signal and the knowledge of the charm particles properties. This ad to the possibility's that in other analysis will use the techniques developed in this work.
Date: January 1, 2005
Creator: Quinones Gonzalez, Jose A. & /Puerto Rico U., Mayaguez
Partner: UNT Libraries Government Documents Department

Study of Inclusive $B^-$ and $\bar{B}^0$ Decays toFlavor-Tagged $D$, $D_s$ and $\Lambda_c$

Description: We report on a study of inclusive B{sup -} and {bar B}{sup 0} meson decays to D{sup 0}X, {bar D}{sup 0}X, D{sup +}X, D{sup -}X, D{sub s}{sup +}X, D{sub s}{sup -}X, {Lambda}{sub c}{sup +}X, {bar {Lambda}}{sub c}{sup -}X, based on a sample of 231 million B{bar B} events recorded with the BABAR detector at the {Upsilon}(4S) resonance. Events are selected by completely reconstructing one B and searching for a reconstructed charm particle in the rest of the event. From the measured branching fractions of these decays, we infer the number of charm and anti-charm particles per {bar B} decay, separately for charged and neutral parents. We derive the total charm yield per B{sup -} decay, n{sub c}{sup -} = 1.202 {+-} 0.023 {+-} 0.040{sub -0.029}{sup +0.035}, and per {bar B}{sup 0} decay, n = 1.193 {+-} 0.030 {+-} 0.034{sub -0.035}{sup +0.044} where the first uncertainty is statistical, the second is systematic, and the third reflects the charm branching-fraction uncertainties. We also present the charm momentum distributions measured in the {bar B} rest frame.
Date: June 15, 2006
Creator: Aubert, B.
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

Triggering BTeV

Description: BTeV is a collider experiment at Fermilab designed for precision studies of CP violation and mixing. Unlike most collider experiments, the BTeV detector has a forward geometry that is optimized for the measurement of B and charm decays in a high-rate environment. While the rate of B production gives BTeV an advantage of almost four orders of magnitude over e{sup +} e{sup {minus}} B factories, the BTeV Level 1 trigger must be able to accept data at a rate of 100 Gigabytes per second, reconstruct tracks and vertices, trigger on B events with high efficiency, and reject minimum bias events by a factor of 100:1. An overview of the Level 1 trigger will be presented.
Date: April 16, 1999
Creator: Gottschalk, Erik
Partner: UNT Libraries Government Documents Department

Searching for new physics with charm

Description: The author considers the prospect of using the charm system as a laboratory for probing new physics. The theoretical expectations for rare charm meson decays, D{sup 0} - {bar D}{sup 0}, and charm quark asymmetries in Z decays are examined in the Standard Model. The effects of new physics from several classes of nonstandard dynamical models are summarized for these phenomena.
Date: June 1995
Creator: Hewett, J. L.
Partner: UNT Libraries Government Documents Department

Signals from flavor changing scalar currents at the future colliders

Description: We present a general phenomenological analysis of a class of Two Higgs Doublet Models with Flavor Changing Neutral Currents arising at the tree level. The existing constraints mainly affect the couplings of the first two generations of quarks, leaving the possibility for non negligible Flavor Changing couplings of the top quark open. The next generation of lepton and hadron colliders will offer the right environment to study the physics of the top quark and to unravel the presence of new physics beyond the Standard Model. In this context we discuss some interesting signals from Flavor Changing Scalar Neutral Currents.
Date: November 22, 1996
Creator: Atwood, D.; Reina, L. & Soni, A.
Partner: UNT Libraries Government Documents Department

From symmetry violation to dynamics: The charm window

Description: C.S. Wu observed parity violation in the low energy process of nuclear decay. She was the first to observe this symmetry violation at any energy. Yet, her work taught us about the form and strengths of the couplings of the massive weak boson. Today, we use the same approach. We look for very much higher mass-scale interactions through symmetry violations in the decays of charm quark systems. These charm decays provide a unique window to new physics.
Date: December 1, 1997
Creator: Appel, J.A.
Partner: UNT Libraries Government Documents Department

Recent results from Fermilab charm Experiment E791

Description: We report the results of some recent E791 charm analyses. They include 1) a search for rare and forbidden decays, 2) measurements of form factors for D{sup +} {yields} K{sup *0}l{sup +}{nu}{sub l} and D{sup +}{sub s} {yields}{phi}l{sup +}{nu}{sub l}, and 3) D{sup +}{sub s} and D{sup 0} lifetime measurements including the lifetime difference between D{sup 0} {yields} K{sup -}{pi}{sup +} and D{sup 0} {yields} K{sup -}K{sup +}. The latter is the first direct search for a possible lifetime difference that could contribute to D{sup 0} - {anti D}{sup 0} mixing.
Date: April 29, 1999
Creator: Sanders, David A.
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

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

Hadronic Charm Decays From B Factories

Description: The B factories, KEKB and PEPII, provide enormous samples of charmed mesons and baryons as well as B{bar B} events. The BELLE and BaBar collaborations have discovered many new particles containing charm quarks in the last few years and have measured their properties with increasing precision. The current status and most recent studies of these charm particle properties is briefly reviewed.
Date: November 9, 2007
Creator: Band, H. R.
Partner: UNT Libraries Government Documents Department

Direct photons at CDF

Description: Direct Photon measurements from the CDF experiment will be described. These include the inclusive photon pt spectrum, photon+jet angular distributions, diphoton production, photon+2jet production, and photon+charm production. Comparisons to QCD predictions will be made.
Date: October 1, 1996
Creator: Nodulman, L.
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

Photons and diphotons from the Tevatron

Description: Photon measurements from the CDF and D0 collaboration are described. The subjects touched on are loosely organized around the fact that they all have some bearing on the structure functions and pQCD. The methodology of collider measurements is briefly reviewed, and the results for single photons, photons plus jets, photons plus charm and diphotons are discussed. Finally there is a very brief indication of what is expected from the Tevatron based experiments in the future.
Date: August 1, 1997
Creator: Blair, R. & Collaborations, CDF and D0
Partner: UNT Libraries Government Documents Department

Charm results on CP violation and mixing

Description: The most recent results on CP violation and mixing in the charm system are reviewed as a guide to the future. While no surprising results are reported so far, charm provides a unique window to physics beyond the Standard Model. The results reported here come from four sources, ALEPH at LEP, E791 and FOCUS/E831 at Fermilab, and CLEO II.V at CESR. Results beyond these sources may be expected as a byproduct of B-motivated experiments.
Date: March 14, 2000
Creator: Appel, J.A.
Partner: UNT Libraries Government Documents Department

Anomalous charm production at large x{sub F}

Description: We show that the new QCD production mechanisms which were proposed by S.J. Brodsky, P. Hoyer, A.H. Mueller and the author can explain at least some of the anomalous behavior of open and/or closed charm production at large x{sub F}.
Date: October 1, 1995
Creator: Tang, W. K.
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