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Kang, Z.B.; Vitev, I.
Brookhaven National Laboratory Riken BNL Research Center (United States). Funding organisation: DOE - Office Of Science (United States)
arXiv e-print [ PDF ]2011
Brookhaven National Laboratory Riken BNL Research Center (United States). Funding organisation: DOE - Office Of Science (United States)
arXiv e-print [ PDF ]2011
AbstractAbstract
[en] We study the photon-triggered light and heavy meson production in both p+p and A+A collisions. We find that a parton energy loss approach that successfully describes inclusive hadron attenuation in nucleus-nucleus reactions at RHIC can simultaneously describe well the experimentally determined photon-triggered light hadron fragmentation functions. Using the same framework, we generalize our formalism to study photon-triggered heavy meson production. We find that the nuclear modification of photon-tagged heavy meson fragmentation functions in A+A collision is very different from that of the photon-tagged light hadron case. While photon-triggered light hadron fragmentation functions in A+A collisions are suppressed relative to p+p, photon-triggered heavy meson fragmentation functions can be either enhanced or suppressed, depending on the specific kinematic region. The anticipated smaller energy loss for b-quarks manifests itself as a flatter photon-triggered B-meson fragmentation function compared to that for the D-meson case. We make detailed predictions for both RHIC and LHC energies. We conclude that a comprehensive comparative study of both photon-tagged light and heavy meson production can provide new insights in the details of the jet quenching mechanism.
Primary Subject
Source
BNL--96334-2011-JA; AC02-98CH10886
Record Type
Journal Article
Journal
Physical Review. D, Particles, Fields, Gravitation and Cosmology; ISSN 1550-7998;
; v. 84(1); p. 014034

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AbstractAbstract
[en] The KEDR detector is a universal magnetic detector designed for studying the c- and b-quarks and two-photon physics, and is employed at the VEPP-4M e+ e− collider. A specific feature of the experiment is the measurement of absolute beam energy using two methods: the resonant depolarization and the faster but less precise Compton backscattering of laser photons. This allowed a large series of measurements to be performed, in which the accuracy of determination of such fundamental parameters of particles as mass and total and leptonic widths was improved.
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Source
Available from http://link.springer.com/openurl/pdf?id=doi:10.1134/S1063779613040035; Copyright (c) 2013 Pleiades Publishing, Ltd.; Country of input: International Atomic Energy Agency (IAEA)
Record Type
Journal Article
Journal
Physics of Particles and Nuclei; ISSN 1063-7796;
; v. 44(4); p. 657-702

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AbstractAbstract
[en] The phenomenon of CP violation and its explanation are of vital interest in our understanding of the structure of matter and perhaps of the excess of matter over anti-matter in the universe. The mixing between quark generations, represented by the CKM matrix, has been suggested as the mechanism responsible for CP violation and particle/anti-particle oscillation observed in neutral K mesons. The elements of the CKM matrix describe the phenomena of CP violation, particle/anti-particle oscillation and inter-generational transitions. All these phenomena were also predicted for hadrons containing the b quark. Since that prediction, particle/anti-particle oscillation has been observed in Bd mesons, however, no evidence has yet been seen for CP violation in the B sector. All the phenomena related to the CKM mixing matrix in the b sector can be summarized in a (unitarity triangle'. Once the sides and angles of this triangle have all been measured, whether or not they form a triangle will determine if the CKM prescription is the correct description of CP violation. We will report about the status of particle oscillation in the B sector as well as on recent attempt to observe asymmetries in the decay of neutral B mesons
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Source
Weizmann Institute of Science, The Faculty of Physics, Rehovot (Israel); 196 p; 8 Apr 1998; p. 111; 44. annual meeting of the Israel Physical Society; Rehovot (Israel); 8 Apr 1998
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Miscellaneous
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Conference
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AbstractAbstract
[en] Six years after the discovery of the Higgs boson, the ATLAS and CMS experiments at CERN have confirmed the decay of this particle in 2 bottom quarks. The measurements made still agree with the predictions of the Standard Model. (A.C.)
Original Title
Du nouveau sur le boson de Higgs
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Source
2 refs.
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Journal Article
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Menke, Sven
Stanford Linear Accelerator Center, Menlo Park, CA (United States). Funding organisation: USDOE Office of Energy Research ER (United States)2002
Stanford Linear Accelerator Center, Menlo Park, CA (United States). Funding organisation: USDOE Office of Energy Research ER (United States)2002
AbstractAbstract
[en] The determination of |Vub| from inclusive semileptonic B decays is limited by uncertainties in modeling the decay distributions in b → u(ell)ν transitions. The largest uncertainties arise from the limited knowledge of the appropriate b quark mass and Fermi momentum to use in the parameterization of the shape function. This paper presents a new method in which these shape function parameters are constrained by the same data used to measure |Vub|. The method requires measurements of the momenta of both the charged lepton and the neutrino in semileptonic B decays. From these quantities two complementary observables can be constructed, one for discriminating between b → u(ell)ν transitions and background and the other for constraining the shape function. Using this technique the uncertainties in |Vub| from the shape function may be significantly reduced
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14 May 2002; [vp.]; AC03-76SF00515; Available from PURL: https://www.osti.gov/servlets/purl/799069-mBB9wD/native/
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Report
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Smith, Mark, E-mail: mark.smith@cern.ch
LHCb collaboration2019
LHCb collaboration2019
AbstractAbstract
[en] Several measurements have shown deviations from lepton universality in tree-level semi-leptonic decays of b hadrons. In these proceedings three LHCb measurements of lepton universality in such decays are presented along with a brief overview for the future possibilities of these and similar observables. (paper)
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BEACH 2018: 13. International Conference on Beauty, Charm and Hyperon Hadrons; Peniche (Portugal); 17-23 Jun 2018; Available from http://dx.doi.org/10.1088/1742-6596/1137/1/012017; Country of input: International Atomic Energy Agency (IAEA)
Record Type
Journal Article
Literature Type
Conference
Journal
Journal of Physics. Conference Series (Online); ISSN 1742-6596;
; v. 1137(1); [5 p.]

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Not Available
Fermi National Accelerator Lab., Batavia, IL (United States). Funding organisation: US Department of Energy (United States)
arXiv e-print [ PDF ]2006
Fermi National Accelerator Lab., Batavia, IL (United States). Funding organisation: US Department of Energy (United States)
arXiv e-print [ PDF ]2006
AbstractAbstract
[en] We report on a measurement of the Bd0 mixing frequency and the calibration of an opposite-side flavor tagger in the D0 experiment. Various properties associated with the b quark on the opposite side of the reconstructed B meson are combined using a likelihood-ratio method into a single variable with enhanced tagging power. Its performance is tested with data, using a large sample of reconstructed semileptonic B → μD0 X and B → μD* X decays, corresponding to an integrated luminosity of approximately 1 fb-1. The events are divided into groups depending on the value of the combined tagging variable, and an independent analysis is performed in each group. Combining the results of these analyses, the overall effective tagging power is found to be (varepsilon)(prime)D2 = (2.48 ± 0.21-0.06+0.08)%. The measured Bd0 mixing frequency Δmd = 0.506 ± 0.020 (stat) ± 0.016 (syst) ps-1 is in good agreement with the world average value
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1 Sep 2006; 19 p; ARXIV EPRINT NUMBER HEP-EX/0609034; AC02-76CH03000; Available from http://lss.fnal.gov/cgi-bin/find_paper.pl?pub-06-341.pdf; PURL: https://www.osti.gov/servlets/purl/897265-0eyFD1/
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Report
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AbstractAbstract
[en] Known perturbative expressions for the decay rates of 115 GeV Higgs particle into either two gluons or a b bar b pair are shown to exhibit renormalization-scale (μ) dependence that is largely removed via renormalization-group or Padeprime-approximant estimates of these rates' next order contributions. The extrema in μ characterizing both rates, as determined from fully known orders of perturbation theory, are very nearly equal to corresponding μ-insensitive rates obtained via estimation of their next order contributions, consistent with 'minimal-sensitivity' expectations
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Othernumber: PRVDAQ000064000001016007000001; 051113PRD; The American Physical Society
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Journal Article
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Adam K Leibovich
Fermi National Accelerator Lab., Batavia, IL (United States). Funding organisation: USDOE Office of Energy Research (ER) (United States)2000
Fermi National Accelerator Lab., Batavia, IL (United States). Funding organisation: USDOE Office of Energy Research (ER) (United States)2000
AbstractAbstract
[en] Current errors on vertbarVubvertbar are dominated by model dependence. For inclusive decays, the model dependence comes from the Fermi motion of the b quark. By combining the endpoint photon and lepton spectra from the inclusive decays B rarrow Xsγ and B rarrow Xuellbar ν, it is possible to remove this model dependence. We show how to combine these rates including the resummation of the end-point logs at next to leading order. The theoretical errors on vertbarVubvertbar on the order of 10% are possible. We also give a brief discussion on comparing different extractions
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30 Nov 2000; 9 p; Radcor 2000; Carmel, CA (United States); Sep 2000; AC02-76CH03000; Available from PURL: https://www.osti.gov/servlets/purl/768527-3SwXyH/native/
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Report
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AbstractAbstract
[en] We discuss the polar angle decay distribution in the decay of on-shell and off-shell polarized (W, Z) gauge bosons into massive quark pairs. In particular for the off-shell decays in it is important to keep the masses of the charm and bottom quarks at their finite values since the scale of the problem is not set by m2 W,Z but by the offshellness of the gauge boson which varies in the range (m 1 + m 2)2 ≤ q 2 ≤ (m H − m W,Z )2.
Primary Subject
Source
Available from http://link.springer.com/openurl/pdf?id=doi:10.1134/S1063779614010419; Copyright (c) 2014 Pleiades Publishing, Ltd.; Country of input: International Atomic Energy Agency (IAEA)
Record Type
Journal Article
Journal
Physics of Particles and Nuclei; ISSN 1063-7796;
; v. 45(1); p. 214-216

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