1,545 research outputs found

    NLO Productions of ω\omega and KS0K^0_{\rm S} with a Global Extraction of the Jet Transport Parameter in Heavy Ion collisions

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    In this work, we pave the way to calculate the productions of ω\omega and KS0K^0_{\rm S} mesons at large pTp_T in p+p and A+A collisions at the RHIC and the LHC. The ω\omega meson fragmentation functions (FFs) in vacuum at next-to-leading order (NLO) are obtained by evolving NLO DGLAP evolution equations with rescaled ω\omega FFs at initial scale Q02=1.5Q_0^2=1.5 GeV2^2 from a broken SU(3) model, and the KS0K^0_{\rm S} FFs in vacuum are taken from AKK08 parametrization directly. Within the framework of the NLO pQCD improved parton model, we make good descriptions of the experimental data on ω\omega and KS0K^0_{\rm S} in p+p both at the RHIC and the LHC. With the higher-twist approach to take into account the jet quenching effect by medium modified FFs, the nuclear modification factors for ω\omega meson and KS0K^0_{\rm S} meson at the RHIC and the LHC are presented with different sets of jet transport coefficient q^0\hat{q}_0. Then we make a global extraction of q^0\hat{q}_0 at the RHIC and the LHC by confronting our model calculations with all available data on 6 identified mesons: π0\pi^0, η\eta, ρ0\rho^0, ϕ\phi, ω\omega, and KS0K^0_{\rm S}. The minimum value of the total χ2/d.o.f\chi^2/d.o.f for productions of these mesons gives the best value of q^0=0.5GeV2/fm\hat{q}_0=0.5\rm GeV^2/fm for Au+Au collisions with sNN=200\sqrt{s_{\rm NN}}=200 GeV at the RHIC, and q^0=1.2GeV2/fm\hat{q}_0=1.2\rm GeV^2/fm for Pb+Pb collisions with sNN=2.76\sqrt{s_{\rm NN}}=2.76 TeV at the LHC respectively, with the QGP spacetime evolution given by an event-by-event viscous hydrodynamics model IEBE-VISHNU. With these global extracted values of q^0\hat{q}_0, the nuclear modification factors of π0\pi^0, η\eta, ρ0\rho^0, ϕ\phi, ω\omega, and KS0K^0_{\rm S} in A+A collisions are presented, and predictions of yield ratios such as ω/π0\omega/\pi^0 and KS0/π0K^0_{\rm S}/\pi^0 at large pTp_T in heavy-ion collisions at the RHIC and the LHC are provided.Comment: 9 pages, 13 figures, 1 tabl

    Muon mass correction in partial wave analyses of charmed meson semi-leptonic decays

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    We derive the parameterization formula for partial wave analyses of charmed meson semi-leptonic decays with consideration of the effects caused by the lepton mass. As the proposed super-tau-charm factory will reach much enhanced luminosity and BESIII is taking ψ(3770)DDˉ\psi(3770)\to D\bar{D} data, our results are helpful to improve the measurement precision of future partial wave analyses of charmed meson semi-muonic decays

    Enhancement of baryon-to-meson ratios around jets as a signature of medium response

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    We present a unique signal of jet-induced medium excitations: the enhancement of baryon-to-meson ratios around the quenched jets. To illustrate this, we study jet-particle correlations and the distributions of jet-induced identified particles with respect to the jet direction in Pb+Pb collisions at the LHC via a multi-phase transport model. We find a strong enhancement of baryon-to-meson ratios for associated particles at intermediate transverse momentum around the triggered jets in Pb+Pb collisions relative to p+p collisions, due to the coalescence of jet-excited medium partons. Since the lost energy from jets can diffuse to large angles, such baryon-to-meson-ratio enhancement is more pronounced for larger relative distance from the jet axis. We argue that the experimental confirmation of the enhancement of jet-induced baryon-to-meson ratios around the jets will provide an unambiguous evidence for the medium response to jet quenching in heavy-ion collisions.Comment: 6 pages, 3 figure

    Photo-production of lowest Σ1/2\Sigma^*_{1/2^-} state within the Regge-effective Lagrangian approach

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    Since the lowest Σ\Sigma^{*} state, with quantum numbers spin-parity JP=1/2J^{P} =1/2^{-}, is far from established experimentally and theoretically, we have performed a theoretical study on the Σ1/2\Sigma^*_{1/2^-} photo-production within the Regge-effective Lagrangian approach. Taking into account that the Σ1/2\Sigma^*_{1/2^-} couples to the KˉN\bar{K}N channel, we have considered the contributions from the tt-channel KK exchange diagram. Moreover, these contributions from tt-channel KK^* exchange, ss-channel nucleon pole, uu-channel Σ\Sigma exchange, and the contact term, are considered. The differential and total cross sections of the process γnK+Σ1/2\gamma n \to K^{+}\Sigma^{*-}_{1/2^-} are predicted with our model parameters. The results should be helpful to search for the Σ1/2\Sigma^*_{1/2^-} state experimentally in future.Comment: 7 pages, 4 figure

    Non-volatile memory based on PZT/FeGa thin film memtranstor

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    The PZT/FeGa thin film memtranstor was prepared and the modulation of the magnetoelectric coefficient by external magnetic and electric fields was studied. The magnetoelectric coefficient of the PZT/FeGa memtranstor can be reversed by flipping the direction of magnetization of FeGa or ferroelectric polarization of PZT. Notably, the sign of the magnetoelectric coefficient can be switched repeatedly by reversing ferroelectric polarization of PZT when the external magnetic field remains constant. Moreover, the binary switching behavior can still be maintained under zero DC bias magnetic field. When the polarization direction remains stable, the magnetoelectric coefficient also does not change. This means that the magnetoelectric coefficient of PZT/FeGa is non-volatile. Furthermore, the retention and endurance characteristics of the PZT/FeGa thin film memtranstor have been investigated. These findings demonstrate the potential of the PZT/FeGa thin film memtranstor for non-volatile memory applications.Comment: 10 pages, 4 figure

    Scalable Incomplete Multi-View Clustering with Structure Alignment

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    The success of existing multi-view clustering (MVC) relies on the assumption that all views are complete. However, samples are usually partially available due to data corruption or sensor malfunction, which raises the research of incomplete multi-view clustering (IMVC). Although several anchor-based IMVC methods have been proposed to process the large-scale incomplete data, they still suffer from the following drawbacks: i) Most existing approaches neglect the inter-view discrepancy and enforce cross-view representation to be consistent, which would corrupt the representation capability of the model; ii) Due to the samples disparity between different views, the learned anchor might be misaligned, which we referred as the Anchor-Unaligned Problem for Incomplete data (AUP-ID). Such the AUP-ID would cause inaccurate graph fusion and degrades clustering performance. To tackle these issues, we propose a novel incomplete anchor graph learning framework termed Scalable Incomplete Multi-View Clustering with Structure Alignment (SIMVC-SA). Specially, we construct the view-specific anchor graph to capture the complementary information from different views. In order to solve the AUP-ID, we propose a novel structure alignment module to refine the cross-view anchor correspondence. Meanwhile, the anchor graph construction and alignment are jointly optimized in our unified framework to enhance clustering quality. Through anchor graph construction instead of full graphs, the time and space complexity of the proposed SIMVC-SA is proven to be linearly correlated with the number of samples. Extensive experiments on seven incomplete benchmark datasets demonstrate the effectiveness and efficiency of our proposed method. Our code is publicly available at https://github.com/wy1019/SIMVC-SA
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