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Revisiting the nature of the Pc pentaquarks

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arXiv 2021年

作者： Du, Meng-Lin Baru, Vadim Guo, Feng-Kun Hanhart, Christoph Meißner, Ulf G. Oller, José A. Wang, Qian Helmholtz-Institut für Strahlen- und Kernphysik Bethe Center for Theoretical Physics Universität Bonn BonnD-53115 Germany Instituto de Física Corpuscular Centro Mixto CSIC-UV Institutos de Investigación de Paterna Apartado 22085 Valencia46071 Spain Institut für Theoretische Physik II Ruhr-Universität Bochum BochumD-44780 Germany Institute for Theoretical and Experimental Physics NRC "Kurchatov Institute" Moscow117218 Russia P.N. Lebedev Physical Institute The Russian Academy of Sciences Leninskiy Prospect 53 Moscow119991 Russia CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences Zhong Guan Cun East Street 55 Beijing100190 China School of Physical Sciences University of Chinese Academy of Sciences Beijing100049 China Institute for Advanced Simulation Institut für Kernphysik Jülich Center for Hadron Physics Forschungszentrum Jülich JülichD-52425 Germany Tbilisi State University Tbilisi0186 Georgia Departamento de Física Universidad de Murcia MurciaE-30071 Spain Guangdong Provincial Key Laboratory of Nuclear Science Institute of Quantum Matter South China Normal University Guangzhou510006 China Guangdong-Hong Kong Joint Laboratory of Quantum Matter Southern Nuclear Science Computing Center South China Normal University Guangzhou510006 China Institute of High Energy Physics Chinese Academy of Sciences Beijing100049 China

The nature of the three narrow hidden-charm pentaquark Pc states, i.e., Pc(4312), Pc(4440) and Pc(4457), is under intense discussion since their discovery from the updated analysis of the process Λ0b → J/ψpK− by LHCb. In this work we extend our previous coupled-channel approach [Phys. Rev. Lett. 124, 072001 (2020)], in which the Pc states are treated as (Formula Presented) molecules, by including the (Formula Presented) and ηcp as explicit inelastic channels in addition to the J/ψp, as required by unitarity and heavy quark spin symmetry (HQSS), respectively. Since inelastic parameters are very badly constrained by the current data, three calculation schemes are considered: (a) scheme I with pure contact interactions between the elastic, i.e., (Formula Presented), and inelastic channels and without the (Formula Presented) interactions, (b) scheme II, where the one-pion exchange (OPE) is added to scheme I, and (c) scheme III, where the (Formula Presented) interactions are included in addition. It is shown that to obtain cutoff independent results, OPE in the multichannel system is to be supplemented with S-wave-to-D-wave mixing contact terms. As a result, in line with our previous analysis, we demonstrate that the experimental data for the J/ψp invariant mass distribution are consistent with the interpretation of the (Formula Presented) hadronic molecules, respectively, and that the data show clear evidence for a new narrow state, Pc(4380), identified as a (Formula Presented) molecule, which should exist as a consequence of HQSS. While two statistically equally good solutions are found in scheme I, only one of these solutions with the quantum numbers of the Pc(4440) and Pc(4457) being JP = 3/2− and 1/2−, respectively, survives the requirement of regulator independence once the OPE is included. Moreover, we predict the line shapes in the elastic and inelastic channels and demonstrate that those related to the Pc(4440) and the (Formula Presented) and ηcp mass distributi

关键词： Hadrons

The power of trading polarity: Evidence from China stock market crash

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arXiv 2018年

作者： Lu, Shan Zhao, Jichang Wang, Huiwen School of Economics and Management Beihang University Beijing China Beijing Key Laboratory of Emergency Support Simulation Technologies for City Operations Beijing China Beijing Advanced Innovation Center for Big Data and Brain Computing Beijing China

The imbalance of buying and selling functions profoundly in the formation of market trends, however, a fine-granularity investigation of the imbalance is still missing. This paper investigates a unique transaction dataset that enables us to inspect the imbalance of buying and selling on the man-times level at high frequency, what we call 'trading polarity', for a large cross-section of stocks from Shenzhen Stock Exchange. The trading polarity measures the market sentiment toward stocks from a view of very essence of trading desire. When using the polarity to examine market crash, we find that trading polarity successfully reects the changing of market-level behavior in terms of its ipping times, depth, and length. We further investigate the relationship between polarity and return. At market-level, trading polarity is negatively correlated with returns, while at stock-level, this correlation changes according to market conditions, which becomes a good signal of market psychology transition. Also, the significant correlation disclosed by the market polarity and market emotion implies that our presented polarity, which essentially calculated in the context of high-frequency trading data, can real-timely reect the sentiment of the market. The trading polarity indeed provides a new way to understand and foresee the market behavior. Copyright © 2018, The Authors. All rights reserved.

关键词： Large dataset

FK/Fπ from Möbius domain-wall fermions solved on gradient-flowed HISQ ensembles

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Physical Review D 2020年第3期102卷 034507-034507页

作者： Nolan Miller Henry Monge-Camacho Chia Cheng Chang (張家丞) Ben Hörz Enrico Rinaldi Dean Howarth Evan Berkowitz David A. Brantley Arjun Singh Gambhir Christopher Körber Christopher J. Monahan M. A. Clark Bálint Joó Thorsten Kurth Amy Nicholson Kostas Orginos Pavlos Vranas André Walker-Loud Department of Physics and Astronomy University of North Carolina Chapel Hill North Carolina 27516-3255 USA Interdisciplinary Theoretical and Mathematical Sciences Program (iTHEMS) RIKEN 2-1 Hirosawa Wako Saitama 351-0198 Japan Nuclear Science Division Lawrence Berkeley National Laboratory Berkeley California 94720 USA Department of Physics University of California Berkeley California 94720 USA Arithmer Inc. R&D Headquarters Minato Tokyo 106-6040 Japan Physics Division Lawrence Livermore National Laboratory Livermore California 94550 USA Department of Physics University of Maryland College Park Maryland 20742 USA Institut für Kernphysik and Institute for Advanced Simulation Forschungszentrum Jülich 54245 Jülich Germany Design Physics Division Lawrence Livermore National Laboratory Livermore California 94550 USA Department of Physics The College of William & Mary Williamsburg Virginia 23187 USA Theory Center Thomas Jefferson National Accelerator Facility Newport News Virginia 23606 USA NVIDIA Corporation 2701 San Tomas Expressway Santa Clara California 95050 USA Scientific Computing Group Thomas Jefferson National Accelerator Facility Newport News Virginia 23606 USA

We report the results of a lattice quantum chromodynamics calculation of FK/Fπ using Möbius domain-wall fermions computed on gradient-flowed Nf=2+1+1 highly improved staggered quark (HISQ) ensembles. The calculation is performed with five values of the pion mass ranging from 130≲mπ≲400 MeV, four lattice spacings of a∼0.15, 0.12, 0.09 and 0.06 fm and multiple values of the lattice volume. The interpolation/extrapolation to the physical pion and kaon mass point, the continuum, and infinite volume limits are performed with a variety of different extrapolation functions utilizing both the relevant mixed-action effective field theory expressions as well as discretization-enhanced continuum chiral perturbation theory formulas. We find that the a∼0.06 fm ensemble is helpful, but not necessary to achieve a subpercent determination of FK/Fπ. We also include an estimate of the strong isospin breaking corrections and arrive at a final result of FK^+/Fπ^+=1.1942(45) with all sources of statistical and systematic uncertainty included. This is consistent with the Flavour Lattice Averaging Group average value, providing an important benchmark for our lattice action. Combining our result with experimental measurements of the pion and kaon leptonic decays leads to a determination of |Vus|/|Vud|=0.2311(10).

关键词： Lattice QCD Leptonic, semileptonic & radiative decays Particle decays Particle mixing & oscillations Quantum chromodynamics

A flexible spatial autoregressive modelling framework for mixed covariates of multiple data types

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arXiv 2018年

作者： Wang, Huiwen Huang, Tingting Wang, Shanshan School of Economics and Management Beihang University Beijing China Beijing Advanced Innovation Center for Big Data and Brain Computing Beihang University Beijing China Beijing Key Laboratory of Emergence Support Simulation Technologies for City Operations Beijing China

Mixed spatial autoregressive (SAR) models with numerical covariates have been well studied. However, as non-numerical data, such as functional data and compositional data, receive substantial amounts of attention and are applied to economics, medicine and meteorology, it becomes necessary to develop exible SAR models with multiple data types. In this article, we integrate three types of covariates, functional, compositional and numerical, in an SAR model. The new model has the merits of classical functional linear models and compositional linear models with scalar responses. Moreover, we develop an estimation method for the proposed model, which is based on functional principal component analysis (FPCA), the isometric logratio (ilr) transformation and the maximum likelihood estimation method. Monte Carlo experiments demonstrate the effectiveness of the estimators. A real dataset is also used to illustrate the utility of the proposed model. Copyright © 2018, The Authors. All rights reserved.

关键词： Principal component analysis

FK/Fπ from möbius domain-wall fermions solved on gradient-flowed hisq ensembles

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arXiv 2020年

作者： Miller, Nolan Monge-Camacho, Henry Chang, Chia Cheng Hörz, Ben Rinaldi, Enrico Howarth, Dean Berkowitz, Evan Brantley, David A. Gambhir, Arjun Singh Körber, Christopher Monahan, Christopher J. Clark, M.A. Joó, Bálint Kurth, Thorsten Nicholson, Amy Orginos, Kostas Vranas, Pavlos Walker-Loud, André Department of Physics and Astronomy University of North Carolina Chapel HillNC27516-3255 United States RIKEN 2-1 Hirosawa Wako Saitama351-0198 Japan Nuclear Science Division Lawrence Berkeley National Laboratory BerkeleyCA94720 United States Department of Physics University of California BerkeleyCA94720 United States Arithmer Inc. R&D Headquarters Minato Tokyo106-6040 Japan Physics Division Lawrence Livermore National Laboratory LivermoreCA94550 United States Department of Physics University of Maryland College ParkMD20742 United States Institut für Kernphysik Institute for Advanced Simulation Forschungszentrum Jülich Jülich54245 Germany Design Physics Division Lawrence Livermore National Laboratory LivermoreCA94550 United States Department of Physics College of William & Mary WilliamsburgVA 23187 United States Theory Center Thomas Jefferson National Accelerator Facility Newport NewsVA23606 United States NVIDIA Corporation 2701 San Tomas Expressway Santa ClaraCA95050 United States Scientific Computing Group Thomas Jefferson National Accelerator Facility Newport NewsVA23606 United States

We report the results of a lattice QCD calculation of FK/Fπ using Möbius Domain-Wall fermions computed on gradient-flowed Nf = 2 + 1 + 1 HISQ ensembles. The calculation is performed with five values of the pion mass ranging from 130. mπ. 400 MeV, four lattice spacings of a ∼ 0.15, 0.12, 0.09 and 0.06 fm and multiple values of the lattice volume. The interpolation/extrapolation to the physical pion and kaon mass point, the continuum, and infinite volume limits are performed with a variety of different extrapolation functions utilizing both the relevant mixed-action effective field theory expressions as well as discretization-enhanced continuum chiral perturbation theory formulas. We find that the a ∼ 0.06 fm ensemble is helpful, but not necessary to achieve a sub-percent determination of FK/Fπ. We also include an estimate of the strong isospin breaking corrections and arrive at a final result of FK + /Fπ+ = 1.1942(45) with all sources of statistical and systematic uncertainty included. This is consistent with the FLAG average value, providing an important benchmark for our lattice action. Combining our result with experimental measurements of the pion and kaon leptonic decays leads to a determination of |Vus|/|Vud| = 0.2311(10). Copyright © 2020, The Authors. All rights reserved.

关键词： Hadrons

Exciton behavior under the influence of metal nanoparticle near fields: Significance of nonlocal effects

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Physical Review B 2018年第11期98卷 115430-115430页

作者： Harini Hapuarachchi Sarath D. Gunapala Qiaoliang Bao Mark I. Stockman Malin Premaratne Advanced Computing and Simulation Laboratory (AχL) Department of Electrical and Computer Systems Engineering Monash University Clayton Victoria 3800 Australia Jet Propulsion Laboratory California Institute of Technology Pasadena California 91109 USA Department of Materials Science and Engineering Monash University Clayton Victoria 3800 Australia Department of Physics and Astronomy Georgia State University Atlanta Georgia 30303 USA

We analytically characterize the influence of a neighboring metal nanoparticle (MNP) on the behavioral trends of a quantum dot (QD) using a generalized nonlocal optical response (GNOR) method based approach, taking the MNP distance dependent modifications to the QD population relaxation and dephasing rates into account. The GNOR model is a recent generalization and an extension of the hydrodynamic Drude model (HDM), which goes beyond HDM by taking into account both the convection current and electron diffusion in the MNPs. It allows unified theoretical explanation of some experimentally observed plasmonic phenomena which otherwise would require ab initio analysis as the conventional local response approximation (LRA) fails to account for them. For example, it has been demonstrated in literature that the GNOR model captures size dependent resonance shifts of small MNPs which are unrevealed by the conventional LRA based methods, and it has proven to yield results displaying better agreement with the experimental observations for plasmonic experiments. Attempts to incorporate MNP nonlocal effects in the analytical characterization of vicinal excitons found in literature utilize the phenomenological hydrodynamic model and assume the absence of MNP interband effects. Moreover, they are only applicable to narrow parameter regions. In this paper we present a complete analytical characterization which overcomes these drawbacks and lends to the perusal of the system over wide continua of various parameters, enabling us to get an elevated view at a much lesser level of complexity compared to the conventional LRA based numerical methods or the conventional ab initio methods of accounting for the nonlocal effects. Our proposed GNOR based model predicts strong modifications to various QD properties such as population difference, absorption, MNP induced shifts to excitonic energy and Förster enhanced broadening, coherent plasmonic field enhancement, and quantum state purity, comp

关键词： Excitons Near-field optics Plasmonics Nanoparticles Quantum dots

Spatial functional linear model and its estimation method

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arXiv 2018年

作者： Huang, Tingting Saporta, Gilbert Wang, Huiwen Wang, Shanshan School of Economics and Management Beihang University Beijing China CEDRIC CNAM 292 rue St Martin Paris Cedex 0375141 France Beijing Advanced Innovation Center for Big Data and Brain Computing Beihang University Beijing China Beijing Key Laboratory of Emergence Support Simulation Technologies for City Operations Beijing China School of Economics and Management Beihang University Xueyuan Road No.37 Haidian District Beijing China

The classical functional linear regression model (FLM) and its extensions, which are based on the assumption that all individuals are mutually independent, have been well studied and are used by many researchers. This independence assumption is sometimes violated in practice, especially when data with a network structure are collected in scientific disciplines including marketing, sociology and spatial economics. However, relatively few studies have examined the applications of FLM to data with network structures. We propose a novel spatial functional linear model (SFLM), that incorporates a spatial autoregressive parameter and a spatial weight matrix into FLM to accommodate spatial dependencies among individuals. The proposed model is relatively flexible as it takes advantage of FLM in handling high-dimensional covariates and spatial autoregressive (SAR) model in capturing network dependencies. We develop an estimation method based on functional principal component analysis (FPCA) and maximum likelihood estimation. simulation studies show that our method performs as well as the FPCA-based method used with FLM when no network structure is present, and outperforms the latter when network structure is present. A real weather data is also employed to demonstrate the utility of the SFLM. Copyright © 2018, The Authors. All rights reserved.

关键词： Economics

Short range operator contributions to 0νββ decay from LQCD

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arXiv 2019年

作者： Monge-Camacho, H. Berkowitz, E. Brantley, D. Chang, C.C. Clark, M.A. Gambhir, A. Garron, N. Joó, B. Kurth, T. Nicholson, A. Rinaldi, E. Tiburzi, B.C. Vranas, P. Walker-Loud, A. Department of Physics and Astronomy University of North Carolina Chapel HillNC27516-3255 United States Department of Physics College of William & Mary WilliamsburgVA 23187 United States Nuclear Science Division Lawrence Berkeley National Laboratory BerkeleyCA94720 United States Institut für Kernphysik Institute for Advanced Simulation Forschungszentrum Jülich Jülich54245 Germany Physics Division Lawrence Livermore National Laboratory LivermoreCA94550 United States RIKEN 2-1 Hirosawa Wako Saitama351-0198 Japan NVIDIA Corporation 2701 San Tomas Expressway Santa ClaraCA95050 United States Theoretical Physics Division Department of Mathematical Sciences University of Liverpool LiverpoolL69 3BX United Kingdom Scientific Computing Group Thomas Jefferson National Accelerator Facility Newport NewsVA23606 United States NERSC Lawrence Berkeley National Laboratory BerkeleyCA94720 United States RIKEN BNL Research Center Brookhaven National Laboratory UptonNY11973 United States Department of Physics The City College of New York New YorkNY10031 United States

The search for neutrinoless double beta decay of nuclei is believed to be one of the most promising means to search for new physics. Observation of this very rare nuclear process, which violates Lepton Number conservation, would imply the neutrino sector has a Majorana mass component and may also provide an explanation for the universe matter-antimatter asymmetry of the universe. In the case where a heavy intermediate particle is exchanged in this process, QCD contributions from short range interactions become relevant and the calculation of matrix elements with four-quark operators becomes necessary. In these proceedings we will discuss our current progress in the calculation of these four-quark operators from LQCD. Copyright © 2019, The Authors. All rights reserved.

关键词： Elementary particles

Short Range Operator Contributions to 0νββ decay from LQCD 36

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Short Range Operator Contributions to 0νββ decay from LQC...

36th Annual International Symposium on Lattice Field Theory, LATTICE 2018

作者： Monge-Camacho, H. Berkowitz, E. Brantley, D. Chang, C.C. Clark, M.A. Gambhir, A. Garron, N. Joó, B. Kurth, T. Nicholson, A. Rinaldi, E. Tiburzi, B.C. Vranas, P. Walker-Loud, A. Department of Physics and Astronomy University of North Carolina Chapel HillNC27516-3255 United States Department of Physics College of William and Mary WilliamsburgVA23187 United States Nuclear Science Division Lawrence Berkeley National Laboratory BerkeleyCA94720 United States Institut für Kernphysik Institute for Advanced Simulation Forschungszentrum Jülich Jülich54245 Germany Physics Division Lawrence Livermore National Laboratory LivermoreCA94550 United States RIKEN 2-1 Hirosawa Wako Saitama351-0198 Japan NVIDIA Corporation 2701 San Tomas Expressway Santa ClaraCA95050 United States Theoretical Physics Division Department of Mathematical Sciences University of Liverpool LiverpoolL69 3BX United Kingdom Scientific Computing Group Thomas Jefferson National Accelerator Facility Newport NewsVA23606 United States NERSC Lawrence Berkeley National Laboratory BerkeleyCA94720 United States RIKEN BNL Research Center Brookhaven National Laboratory UptonNY11973 United States Department of Physics City College of New York New YorkNY10031 United States

The search for neutrinoless double beta decay of nuclei is believed to be one of the most promising means to search for new physics. Observation of this very rare nuclear process, which violates Lepton Number conservation, would imply the neutrino sector has a Majorana mass component and may also provide an explanation for the universe matter-antimatter asymmetry of the universe. In the case where a heavy intermediate particle is exchanged in this process, QCD contributions from short range interactions become relevant and the calculation of matrix elements with four-quark operators becomes necessary. In these proceedings we will discuss our current progress in the calculation of these four-quark operators from LQCD. © Copyright owned by the author(s) under the terms of the Creative Commons.

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