5,652 research outputs found

    Annihilation Rates of Heavy 1βˆ’βˆ’1^{--} S-wave Quarkonia in Salpeter Method

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    The annihilation rates of vector 1βˆ’βˆ’1^{--} charmonium and bottomonium 3S1^3S_1 states Vβ†’e+eβˆ’V \rightarrow e^+e^- and Vβ†’3Ξ³V\rightarrow 3\gamma, Vβ†’Ξ³ggV \rightarrow \gamma gg and Vβ†’3gV \rightarrow 3g are estimated in the relativistic Salpeter method. We obtained Ξ“(J/Οˆβ†’3Ξ³)=6.8Γ—10βˆ’4\Gamma(J/\psi\rightarrow 3\gamma)=6.8\times 10^{-4} keV, Ξ“(ψ(2S)β†’3Ξ³)=2.5Γ—10βˆ’4\Gamma(\psi(2S)\rightarrow 3\gamma)=2.5\times 10^{-4} keV, Ξ“(ψ(3S)β†’3Ξ³)=1.7Γ—10βˆ’4\Gamma(\psi(3S)\rightarrow 3\gamma)=1.7\times 10^{-4} keV, Ξ“(Ξ₯(1S)β†’3Ξ³)=1.5Γ—10βˆ’5\Gamma(\Upsilon(1S)\rightarrow 3\gamma)=1.5\times 10^{-5} keV, Ξ“(Ξ₯(2S)β†’3Ξ³)=5.7Γ—10βˆ’6\Gamma(\Upsilon(2S)\rightarrow 3\gamma)=5.7\times 10^{-6} keV, Ξ“(Ξ₯(3S)β†’3Ξ³)=3.5Γ—10βˆ’6\Gamma(\Upsilon(3S)\rightarrow 3\gamma)=3.5\times 10^{-6} keV and Ξ“(Ξ₯(4S)β†’3Ξ³)=2.6Γ—10βˆ’6\Gamma(\Upsilon(4S)\rightarrow 3\gamma)=2.6\times 10^{-6} keV. In our calculations, special attention is paid to the relativistic correction, which is important and can not be ignored for excited 2S2S, 3S3S and higher excited states.Comment: 10 pages,2 figures, 5 table

    Zero-Shot Visual Recognition using Semantics-Preserving Adversarial Embedding Networks

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    We propose a novel framework called Semantics-Preserving Adversarial Embedding Network (SP-AEN) for zero-shot visual recognition (ZSL), where test images and their classes are both unseen during training. SP-AEN aims to tackle the inherent problem --- semantic loss --- in the prevailing family of embedding-based ZSL, where some semantics would be discarded during training if they are non-discriminative for training classes, but could become critical for recognizing test classes. Specifically, SP-AEN prevents the semantic loss by introducing an independent visual-to-semantic space embedder which disentangles the semantic space into two subspaces for the two arguably conflicting objectives: classification and reconstruction. Through adversarial learning of the two subspaces, SP-AEN can transfer the semantics from the reconstructive subspace to the discriminative one, accomplishing the improved zero-shot recognition of unseen classes. Comparing with prior works, SP-AEN can not only improve classification but also generate photo-realistic images, demonstrating the effectiveness of semantic preservation. On four popular benchmarks: CUB, AWA, SUN and aPY, SP-AEN considerably outperforms other state-of-the-art methods by an absolute performance difference of 12.2\%, 9.3\%, 4.0\%, and 3.6\% in terms of harmonic mean value
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