13,117 research outputs found

    Study of the K1(1270)βˆ’K1(1400)K_1(1270)-K_1(1400) mixing in the decays Bβ†’J/Ξ¨K1(1270),J/Ξ¨K1(1400)B\to J/\Psi K_1(1270), J/\Psi K_1(1400)

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    We studied the B meson decays Bβ†’J/Ξ¨K1(1270,1400)B\to J/\Psi K_1(1270,1400) in the pQCD approach beyond the leading order. With the vertex corrections and the NLO Wilson coefficients included, the branching ratios of the considered decays are Br(B+β†’J/Ξ¨K1(1270)+)=1.76βˆ’0.69+0.65Γ—10βˆ’3,Br(B+β†’J/Ξ¨K1(1400)+)=7.03βˆ’2.52+2.70Γ—10βˆ’4Br(B^+\to J/\Psi K_1(1270)^+)=1.76^{+0.65}_{-0.69}\times10^{-3}, Br(B^+\to J/\Psi K_1(1400)^+)=7.03^{+2.70}_{-2.52}\times10^{-4}, and Br(B0β†’J/Ξ¨K1(1270)0)=(1.63βˆ’0.64+0.60)Γ—10βˆ’3Br(B^0\to J/\Psi K_1(1270)^0)=(1.63^{+0.60}_{-0.64})\times10^{-3} with the mixing angle ΞΈK1=33∘\theta_{K_1}=33^\circ, which can agree well with the data or the present experimental upper limit within errors. So we support the opinion that ΞΈK1∼33∘\theta_{K_1}\sim33^\circ is much more favored than 58∘58^{\circ}. Furthermore, we also give the predictions for the polarization fractions, direct CP violations from the different polarization components, the relative phase angles for the considered decays with the mixing angle ΞΈK1=33∘\theta_{K_1}=33^\circ and 58∘58^\circ, respectively. The direct CP violations of the two charged decays B+β†’J/Ξ¨K1(1270,1400)+B^+\to J/\Psi K_1(1270,1400)^+ are very small (10βˆ’4∼10βˆ’5)(10^{-4}\sim10^{-5}), because there is no weak phase until up to O(Ξ»4)\mathcal{O}(\lambda^4) with the Wolfenstein parameter Ξ»=0.22537\lambda=0.22537. These results can be tested at the running LHCb and forthcoming Super-B experiments.Comment: 14 pages,3 figures,to appear in EPJ

    ME-Net: Towards Effective Adversarial Robustness with Matrix Estimation

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    Deep neural networks are vulnerable to adversarial attacks. The literature is rich with algorithms that can easily craft successful adversarial examples. In contrast, the performance of defense techniques still lags behind. This paper proposes ME-Net, a defense method that leverages matrix estimation (ME). In ME-Net, images are preprocessed using two steps: first pixels are randomly dropped from the image; then, the image is reconstructed using ME. We show that this process destroys the adversarial structure of the noise, while re-enforcing the global structure in the original image. Since humans typically rely on such global structures in classifying images, the process makes the network mode compatible with human perception. We conduct comprehensive experiments on prevailing benchmarks such as MNIST, CIFAR-10, SVHN, and Tiny-ImageNet. Comparing ME-Net with state-of-the-art defense mechanisms shows that ME-Net consistently outperforms prior techniques, improving robustness against both black-box and white-box attacks.Comment: ICML 201

    An improved method to test the Distance--Duality relation

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    Many researchers have performed cosmological-model-independent tests for the distance duality (DD) relation. Theoretical work has been conducted based on the results of these tests. However, we find that almost all of these tests were perhaps not cosmological-model-independent after all, because the distance moduli taken from a given type Ia supernovae (SNe Ia) compilation are dependent on a given cosmological model and Hubble constant. In this Letter, we overcome these defects and by creating a new cosmological-model-independent test for the DD relation. We use the original data from the Union2 SNe Ia compilation and the angular diameter distances from two galaxy cluster samples compiled by De Filippis et al. and Bonamente et al. to test the DD relation. Our results suggest that the DD relation is compatible with observations, and the spherical model is slightly better than the elliptical model at describing the intrinsic shape of galaxy clusters if the DD relation is valid. However, these results are different from those of previous work.Comment: 5 pages, 2 figures, published on ApJ

    Some new applications for heat and fluid flows via fractional derivatives without singular kernel

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    This paper addresses the mathematical models for the heat-conduction equations and the Navier-Stokes equations via fractional derivatives without singular kernel.Comment: This is a preprint of a paper whose final and definite form will be published in Thermal Science. Paper Submitted 28/ Dec /2016; Revised 20/Jan/2016; Accepted for publication 21/Jan/201
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