Using pp collision data collected by LHCb at center-of-mass energies s=7 TeV and 8 TeV, corresponding to an integrated luminosity of 3 fb−1, the ratio of the branching fraction of the Bc+→ψ(2S)π+ decay relative t...
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Using pp collision data collected by LHCb at center-of-mass energies s=7 TeV and 8 TeV, corresponding to an integrated luminosity of 3 fb−1, the ratio of the branching fraction of the Bc+→ψ(2S)π+ decay relative to that of the Bc+→J/ψπ+ decay is measured to be 0.268±0.032(stat)±0.007(syst)±0.006(BF). The first uncertainty is statistical, the second is systematic, and the third is due to the uncertainties on the branching fractions of the J/ψ→μ+μ− and ψ(2S)→μ+μ− decays. This measurement is consistent with the previous LHCb result, and the statistical uncertainty is halved.
An analysis of the decays of B∓→DK∓ and B∓→Dπ∓ is presented in which the D meson is reconstructed in the three-body final states K∓π±π0, π+π−π0 and K+K−π0. Using data from LHCb corresponding to an integr...
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An analysis of the decays of B∓→DK∓ and B∓→Dπ∓ is presented in which the D meson is reconstructed in the three-body final states K∓π±π0, π+π−π0 and K+K−π0. Using data from LHCb corresponding to an integrated luminosity of 3.0 fb−1 of pp collisions, measurements of several CP observables are performed. First observations are obtained of the suppressed Atwood-Dunietz-Soni decay B∓→[π∓K±π0]Dπ∓ and the quasi-Gronau-London-Wyler decay B∓→[K+K−π0]Dπ∓. The results are interpreted in the context of the unitarity triangle angle γ and related parameters.
The resonant substructures of B0→D¯0π+π− decays are studied with the Dalitz plot technique. In this study a data sample corresponding to an integrated luminosity of 3.0 fb−1 of pp collisions collected by the ...
The resonant substructures of B0→D¯0π+π− decays are studied with the Dalitz plot technique. In this study a data sample corresponding to an integrated luminosity of 3.0 fb−1 of pp collisions collected by the LHCb detector is used. The branching fraction of the B0→D¯0π+π− decay in the region m(D¯0π±)>2.1 GeV/c2 is measured to be (8.46±0.14±0.29±0.40)×10−4, where the first uncertainty is statistical, the second is systematic and the last arises from the normalization channel B0→D*(2010)−π+. The π+π− S-wave components are modeled with the isobar and K-matrix formalisms. Results of the Dalitz plot analyses using both models are presented. A resonant structure at m(D¯0π−)≈2.8 GeV/c2 is confirmed and its spin-parity is determined for the first time as JP=3−. The branching fraction, mass and width of this structure are determined together with those of the D0*(2400)− and D2*(2460)− resonances. The branching fractions of other B0→D¯0h0 decay components with h0→π+π− are also reported. Many of these branching fraction measurements are the most precise to date. The first observation of the decays B0→D¯0f0(500), B0→D¯0f0(980), B0→D¯0ρ(1450), B0→D3*(2760)−π+ and the first evidence of B0→D¯0f0(2020) are presented.
The Dalitz plot distribution of B0→D¯0K+π− decays is studied using a data sample corresponding to 3.0 fb−1 of pp collision data recorded by the LHCb experiment during 2011 and 2012. The data are described by a...
The Dalitz plot distribution of B0→D¯0K+π− decays is studied using a data sample corresponding to 3.0 fb−1 of pp collision data recorded by the LHCb experiment during 2011 and 2012. The data are described by an amplitude model that contains contributions from intermediate K*(892)0, K*(1410)0, K2*(1430)0 and D2*(2460)− resonances. The model also contains components to describe broad structures, including the K0*(1430)0 and D0*(2400)− resonances, in the Kπ S-wave and the Dπ S- and P-waves. The masses and widths of the D0*(2400)− and D2*(2460)− resonances are measured, as are the complex amplitudes and fit fractions for all components included in the amplitude model. The model obtained will be an integral part of a future determination of the angle γ of the Cabibbo-Kobayashi-Maskawa quark mixing matrix using B0→DK+π− decays.
The B−→D+K−π− decay is observed in a data sample corresponding to 3.0 fb−1 of pp collision data recorded by the LHCb experiment during 2011 and 2012. Its branching fraction is measured to be B(B−→D+K−π−)=(7.31...
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The B−→D+K−π− decay is observed in a data sample corresponding to 3.0 fb−1 of pp collision data recorded by the LHCb experiment during 2011 and 2012. Its branching fraction is measured to be B(B−→D+K−π−)=(7.31±0.19±0.22±0.39)×10−5 where the uncertainties are statistical, systematic and from the branching fraction of the normalization channel B−→D+π−π−, respectively. An amplitude analysis of the resonant structure of the B−→D+K−π− decay is used to measure the contributions from quasi-two-body B−→D0*(2400)0K−, B−→D2*(2460)0K−, and B−→DJ*(2760)0K− decays, as well as from nonresonant sources. The DJ*(2760)0 resonance is determined to have spin 1.
The associated production of a W boson with a jet originating from either a light parton or heavy-flavor quark is studied in the forward region using proton-proton collisions. The analysis uses data corresponding to i...
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The associated production of a W boson with a jet originating from either a light parton or heavy-flavor quark is studied in the forward region using proton-proton collisions. The analysis uses data corresponding to integrated luminosities of 1.0 and 2.0 fb−1 collected with the LHCb detector at center-of-mass energies of 7 and 8 TeV, respectively. The W bosons are reconstructed using the W→μν decay and muons with a transverse momentum, pT, larger than 20 GeV in the pseudorapidity range 2.0<η<4.5. The partons are reconstructed as jets with pT>20 GeV and 2.2<η<4.2. The sum of the muon and jet momenta must satisfy pT>20 GeV. The fraction of W+jet events that originate from beauty and charm quarks is measured, along with the charge asymmetries of the W+b and W+c production cross sections. The ratio of the W+jet to Z+jet production cross sections is also measured using the Z→μμ decay. All results are in agreement with Standard Model predictions.
Angular correlations in B+→X(3872)K+ decays, with X(3872)→ρ0J/ψ, ρ0→π+π− and J/ψ→μ+μ−, are used to measure orbital angular momentum contributions and to determine the JPC value of the X(3872) meson. The da...
Angular correlations in B+→X(3872)K+ decays, with X(3872)→ρ0J/ψ, ρ0→π+π− and J/ψ→μ+μ−, are used to measure orbital angular momentum contributions and to determine the JPC value of the X(3872) meson. The data correspond to an integrated luminosity of 3.0 fb−1 of proton-proton collisions collected with the LHCb detector. This determination, for the first time performed without assuming a value for the orbital angular momentum, confirms the quantum numbers to be JPC=1++. The X(3872) is found to decay predominantly through an S wave and an upper limit of 4% at 95% C.L. is set on the D-wave contribution.
A search for the rare decay of a B0 or Bs0 meson into the final state J/ψγ is performed, using data collected by the LHCb experiment in pp collisions at s=7 and 8 TeV, corresponding to an integrated luminosity of 3 ...
A search for the rare decay of a B0 or Bs0 meson into the final state J/ψγ is performed, using data collected by the LHCb experiment in pp collisions at s=7 and 8 TeV, corresponding to an integrated luminosity of 3 fb−1. The observed number of signal candidates is consistent with a background-only hypothesis. Branching fraction values larger than 1.5×10−6 for the B0→J/ψγ decay mode are excluded at 90% confidence level. For the Bs0→J/ψγ decay mode, branching fraction values larger than 7.3×10−6 are excluded at 90% confidence level; this is the first branching fraction limit for this decay.
We report a study of the suppressed B−→DK−π+π− and favored B−→Dπ−π+π− decays, where the neutral D meson is detected through its decays to the K∓π± and CP -even K+K− and π+π− final states. The measuremen...
We report a study of the suppressed B−→DK−π+π− and favored B−→Dπ−π+π− decays, where the neutral D meson is detected through its decays to the K∓π± and CP -even K+K− and π+π− final states. The measurement is carried out using a proton-proton collision data sample collected by the LHCb experiment, corresponding to an integrated luminosity of 3.0 fb−1. We observe the first significant signals in the CP -even final states of the D meson for both the suppressed B−→DK−π+π− and favored B−→Dπ−π+π− modes, as well as in the doubly Cabibbo suppressed D→K+π− final state of the B−→Dπ−π+π− decay. Evidence for the suppressed decay B−→DK−π+π−, with D→K+π−, is also presented. From the observed yields in the B−→DK−π+π−, B−→Dπ−π+π− and their charge conjugate decay modes, the most probable value of the weak phase γ corresponds to γ=(74−19+20)°. This is one of the most precise single-measurement determinations of γ to date.
作者:
TUCK, EFPATTERSON, DPSTUART, JRLAWRENCE, MHCalling Communications Corporation. 1900 West Garvey Ave
South. Suite 200 West Covina CA 91790 USA. Chairman of Calling Communications Corporation. He is also the Managing Director of Kinship Venture Management
Inc. the general partner of Kinship Partners 11 and a General Partner of Boundary the general partner of The Boundary Fund. As a venture capitalist he has founded or participated in founding several telecommunications companies including Calling Communications Corporation Magellan Systems Corporation
manufactures of Global Positioning System receivers Applied Digital Access
manufacturer of DS-3 test access and network performance monitoring equipment Endgate Technology Corporation
specialists in satellite phased array antennas and Poynting Systems Corporation. now a division of Reliance Corporation
manufacturers of fibre optic transport equipment. He was a founder of Kebby Microwave Corporation where he invented the first solid-state. frequency-modulated commercial microwave link system. The company was acquired by ITT Corporation where he rose to the position of V.P. and Technical Director of ITT North America Telecommunications Inc. Subsequently he was V.P. of Marketing and Engineering at American Telecommunications Inc. (ATC). He was founding Director of American Telecom Inc. a joint venture between ATC and Fujitsu and has served on more than 20 boards of directors including those of three public companies. He has authored articles on microwave engineering and telephone signalling and was a contributor to Reference Data For Radio Engineers. He is a graduate of the University of Missouri at Rolla where he was later awarded an honorary Professional degree and serves on its Academy of Electrical Engineering. Mr Tuck is a Senior Member of the IEEE a Fellow of the Institution of Engineers (Australia) a Professional Member of the AIAA and a registered professional engineer in three states. More than 25 years of experience in the telecommunications industry where he has been responsibl
There is a very large demand for basic telephone service in developing nations, and remote parts of industrialized nations, which cannot be met by conventional wireline and cellular systems. This is the world's la...
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There is a very large demand for basic telephone service in developing nations, and remote parts of industrialized nations, which cannot be met by conventional wireline and cellular systems. This is the world's largest unserved market. We describe a system which uses recent advances in active phased arrays, fast-packet switching technology, adaptive routeing, and light spacecraft technology, in part based on the work of the Jet Propulsion laboratory and on recently-declassified work done on the Strategic Defense Initiative, to make it possible to address this market with a global telephone network based on a large low-Earth-orbit constellation of identical satellites. A telephone utility can use such a network to provide the same modern basic and enhanced telephone services offered by telephone utilities in the urban centres of fully-industrialized nations. Economies of scale permit capital and operating costs per subscriber low enough to provide a service to all subscribers, regardless of location, at prices comparable to the same services in urban areas of industrialized nations, while generating operating profits great enough to attract the capital needed for its construction. The bandwidth needed to support the capacity needed to gain these economies of scale requires that the system use K(alpha)-band frequencies. This choice of frequencies places unusual constraints on the network design, and in particular forces the use of a large number of satellites. Global demand for basic and enhanced telephone service is great enough to support at least three networks of the size described herein. The volume of advanced components, and services such as launch services, required to construct and replace these networks is sufficient to propel certain industries to market leadership positions in the early 21st Century.
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