33,038 research outputs found

    Pose-Guided Multi-Granularity Attention Network for Text-Based Person Search

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    Text-based person search aims to retrieve the corresponding person images in an image database by virtue of a describing sentence about the person, which poses great potential for various applications such as video surveillance. Extracting visual contents corresponding to the human description is the key to this cross-modal matching problem. Moreover, correlated images and descriptions involve different granularities of semantic relevance, which is usually ignored in previous methods. To exploit the multilevel corresponding visual contents, we propose a pose-guided multi-granularity attention network (PMA). Firstly, we propose a coarse alignment network (CA) to select the related image regions to the global description by a similarity-based attention. To further capture the phrase-related visual body part, a fine-grained alignment network (FA) is proposed, which employs pose information to learn latent semantic alignment between visual body part and textual noun phrase. To verify the effectiveness of our model, we perform extensive experiments on the CUHK Person Description Dataset (CUHK-PEDES) which is currently the only available dataset for text-based person search. Experimental results show that our approach outperforms the state-of-the-art methods by 15 \% in terms of the top-1 metric.Comment: published in AAAI2020(oral

    The order p8p^8 mesonic chiral Lagrangian

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    We derive the chiral Lagrangian at next-to-next-to-next-to-leading order (NNNLO) for a general number NfN_f of light quark flavours as well as for Nf=2,3N_f=2,3. We enumerate the contact terms separately. We also discuss the cases where some of the external fields are not included. An example of a choice of Lagrangian is given in the supplementary material.Comment: 23 pages, The file basis.pdf contains the full basis. Minor misprints corrected w.r.t. v

    Pair Production of Doubly-Charged Scalars: Neutrino Mass Constraints and Signals at the LHC

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    We study the pair production of doubly charged Higgs bosons at the Large Hadron Collider (LHC), assuming the doubly charged Higgs to be part of an SU(2)_L triplet which generates Majorana masses for left-handed neutrinos. Such pair-production has the advantage that it is not constrained by the triplet vacuum expectation value, which tends to make the single production rate rather small. We point out that, in addition to the Drell-Yan (DY) production mechanism, two-photon processes also contribute to H++H++ production at a level comparable to the QCD corrections to the DY channel. Decays of the doubly charged Higgs into both the l+l+ and W+W+ modes are studied in detail to optimize the signal observation over the backgrounds. Doubly charged scalars should be observable at the LHC with 300 fb^-1 integrated luminosity in the ll channel upto the mass range of 1 TeV even with a branching fraction of about 60 %, and in the WW channel upto a mass of 700 GeV. Such a doubly charged Higgs, if it is a member of a triplet generating neutrino masses,cannot be long-lived on the scale of collider detectors although it might lead to a displaced secondary vertex during its decay if it is lighter than about 250 GeV.Comment: revtex4, 23 pages, 14 figures, version published in Physical Review

    Quantum critical dynamics for a prototype class of insulating antiferromagnets

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    Quantum criticality is a fundamental organizing principle for studying strongly correlated systems. Nevertheless, understanding quantum critical dynamics at nonzero temperatures is a major challenge of condensed matter physics due to the intricate interplay between quantum and thermal fluctuations. The recent experiments in the quantum spin dimer material TlCuCl3_3 provide an unprecedented opportunity to test the theories of quantum criticality. We investigate the nonzero temperature quantum critical spin dynamics by employing an effective O(N)O(N) field theory. The on-shell mass and the damping rate of quantum critical spin excitations as functions of temperature are calculated based on the renormalized coupling strength, which are in excellent agreements with experiment observations. Their Tln⁑TT\ln T dependence is predicted to be dominant at very low temperatures, which is to be tested in future experiments. Our work provides confidence that quantum criticality as a theoretical framework, being considered in so many different contexts of condensed matter physics and beyond, is indeed grounded in materials and experiments accurately. It is also expected to motivate further experimental investigations on the applicability of the field theory to related quantum critical systems.Comment: 9 pages, 7 figure

    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
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