3,314 research outputs found

    NRQCD Predictions of D-Wave Quarkonia 3DJ(J=1,2,3)^3D_{J}(J=1,2,3) Decay into Light Hadrons at Order αs3\alpha_{s}^{3}

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    In this paper, in the framework of NRQCD we study the light hadron (LH) decays of the spin-triplet (S=1) D-wave heavy quarkonia. The short distance coefficients of all Fock states in the 3DJ(J=1,2,3)^3D_J(J=1,2,3) quarkonia including D-wave color-singlet, P-wave color-octet and S-wave color-singlet and color-octet are calculated perturbatively at αs3\alpha_{s}^3 order. The operator evolution equations of the four-fermion operators are also derived and are used to estimate the numerical values of the long distance matrix elements. We find that for the ccˉc\bar{c} system, the LH decay widths of ψ(13DJ)\psi(1^3D_J) predicted by NRQCD is about 2∼32\sim3 times larger than the phenomenological potential model results, while for the bbˉb\bar{b} system the two theoretical estimations of Γ(Υ(13DJ)→LH)\Gamma(\Upsilon(1^3D_J)\to LH) are in coincidence with each other. Our predictions for ψ(13DJ)\psi(1^3D_J) LH decay widths are Γ(ψ(13DJ)→LH)=(0.43,0.05,0.17)\Gamma(\psi(1^3D_J)\to LH)=(0.43,0.05,0.17)MeV for J=1,2,3; and for Υ(13DJ)\Upsilon(1^3D_J), Γ(Υ(13DJ)→LH)=(6.91,0.75,2.75)\Gamma(\Upsilon(1^3D_J)\to LH)=(6.91,0.75,2.75)KeV for J=1,2,3.Comment: 12 figures, references added, published version in PR

    CleanNet: Transfer Learning for Scalable Image Classifier Training with Label Noise

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    In this paper, we study the problem of learning image classification models with label noise. Existing approaches depending on human supervision are generally not scalable as manually identifying correct or incorrect labels is time-consuming, whereas approaches not relying on human supervision are scalable but less effective. To reduce the amount of human supervision for label noise cleaning, we introduce CleanNet, a joint neural embedding network, which only requires a fraction of the classes being manually verified to provide the knowledge of label noise that can be transferred to other classes. We further integrate CleanNet and conventional convolutional neural network classifier into one framework for image classification learning. We demonstrate the effectiveness of the proposed algorithm on both of the label noise detection task and the image classification on noisy data task on several large-scale datasets. Experimental results show that CleanNet can reduce label noise detection error rate on held-out classes where no human supervision available by 41.5% compared to current weakly supervised methods. It also achieves 47% of the performance gain of verifying all images with only 3.2% images verified on an image classification task. Source code and dataset will be available at kuanghuei.github.io/CleanNetProject.Comment: Accepted to CVPR 201

    Probing Electroweak Symmetry Breaking Mechanism at the LHC: A Guideline from Power Counting Analysis

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    We formulate the equivalence theorem as a theoretical criterion for sensitively probing the electroweak symmetry breaking mechanism, and develop a precise power counting method for the chiral Lagrangian formulated electroweak theories. Armed with these, we perform a systematic analysis on the sensitivities of the scattering processes W±W±→W±W±W^\pm W^\pm \rightarrow W^\pm W^\pm and qqˉ′→W±Zq\bar{q}'\rightarrow W^\pm Z for testing all possible effective bosonic operators in the chiral Lagrangian formulated electroweak theories at the CERN Large Hadron Collider (LHC). The analysis shows that these two kinds of processes are "complementary" in probing the electroweak symmetry breaking sector.Comment: Extended version, 11-page-Latex-file and 3 separate PS-Figs. To be Published in Mod.Phys.Lett.

    Sensitivity of the LHC to Electroweak Symmetry Breaking: Equivalence Theorem as a Criterion

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    Based upon our recent study on the intrinsic connection between the longitudinal weak-boson scatterings and probing the electroweak symmetry breaking (EWSB) mechanism, we reveal the profound physical content of the Equivalence Theorem (ET) as being able to discriminate physical processes which are sensitive/insensitive to probing the EWSB sector. With this physical content of the ET as a criterion, we analyze the complete set of the bosonic operators in the electroweak chiral Lagrangian and systematically classify the sensitivities to probing all these operators at the CERN LHC via the weak-boson fusion in W±W±W^\pm W^\pm channel. This is achieved by developing a precise power counting rule (a generalization from Weinberg's counting method) to {\it separately} count the power dependences on the energy EE and all relevant mass scales.Comment: 33 pages, LaTeX, 10 figures and Table-1b are in the separate file figtab.uu. (The only change made from the previous version is to fix the bugs in the uuencoded file.

    Comment on "Chiral Suppression of Scalar Glueball Decay"

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    Comment on ``Chiral Suppression of Scalar Glueball Decay''Comment: Comment published in Phys. Rev. Lett. 98, 149103(2007

    Longitudinal/Goldstone boson equivalence and phenomenology of probing the electroweak symmetry breaking

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    We formulate the equivalence between the longitudinal weak-boson and the Goldstone boson as a criterion for sensitively probing the electroweak symmetry breaking mechanism and develop a precise power counting rule for chiral Lagrangian formulated electroweak theories. With these we semi-quatitatively analyze the sensitivities to various effective operators related to electrowaeak symmetry breaking via weak-boson scatterings at the CERN Large Hadron Collider (LHC).Comment: 6 pages, LaTex, 1 postscript figure included using psfig.te

    Search for C=+C=+ charmonium and bottomonium states in e+e−→γ+Xe^+e^-\to \gamma+ X at B factories

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    We study the production of C=+C=+ charmonium states XX in e+e−→γ+Xe^+e^-\to \gamma + X at B factories with X=ηc(nS)X=\eta_c(nS) (n=1,2,3), χcJ(mP)\chi_{cJ}(mP) (m=1,2), and 1D2(1D)^1D_2(1D). In the S and P wave case, contributions of tree-QED with one-loop QCD corrections are calculated within the framework of nonrelativistic QCD(NRQCD) and in the D-wave case only the tree-QED contribution are considered. We find that in most cases the QCD corrections are negative and moderate, in contrast to the case of double charmonium production e+e−→J/ψ+Xe^+e^-\to J/\psi + X, where QCD corrections are positive and large in most cases. We also find that the production cross sections of some of these states in e+e−→γ+Xe^+e^-\to \gamma + X are larger than that in e+e−→J/ψ+Xe^+e^-\to J/\psi + X by an order of magnitude even after the negative QCD corrections are included. So we argue that search for the X(3872), X(3940), Y(3940), and X(4160) in e+e−→γ+Xe^+e^-\to \gamma + X at B factories may be helpful to clarify the nature of these states. For completeness, the production of bottomonium states in e+e−e^+e^- annihilation is also discussed.Comment: 13pages, 4 figure
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