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Ds0(2317) and Ds1(2460) in an unquenched quark model

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arXiv 2021年

作者： Tan, Yue Ping, Jialun Department of Physics Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal University Nanjing210023 China

Recently, BESIII Collaboration updated the data of exotic state, D∗s0(2317), with mass at 2318.3 ± 1.2 ± 1.2 MeV in the positronium annihilation process. Inspired by experiment, We study the two hot exotic states, Ds∗0(2317) and Ds1(2460), in the more reasonable unquenched quark model with two modified factor: the one is distance convergence, while the other is energy suppression. Different from the other works, we first give all of possible the mass shift and component of Ds∗0(2317) and Ds1(2460) at the same time. All the calculation are done with the help of Gaussian expansion method, which is very accurate few body system calculation method. In addition, not only DK(D∗K) but also the other OZI allowed mesonium including Dsη are all taken into consideration. We propose an unquenched quark model to give a unitive description for Ds spectrum including four particles: Ds, Ds∗, Ds∗0(2317) and Ds1(2460), and the results show that Ds∗0(2317) and Ds1(2460) are a cs¯ sate plus an extra important component due to continuum while Ds and Ds∗ are almost pure quark-antiquark state. Copyright © 2021, The Authors. All rights reserved.

关键词： Hadrons

Investigation of hidden-charm Pentaquarks with strangeness S = −1

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arXiv 2021年

作者： Hu, Xiaohuang Ping, Jialun Department of Physics Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal University Nanjing210023 China

Recently, a new hidden-charm pentaquark state Pcs(4459) was reported by the LHCb Collaboration. Stimulated by the fact that all hidden-charm pentaquark states in S = 0 systems were successfully studied by the chiral quark model, we extended this study to the S = −1 systems. All possible states with quantum numbers IJP = 0(12)−, 0(23)−, 0(25)−, 1(21)−, 1(23)− and 1(25)− have been investigated. The calculation results shows that the newly observed state Pcs(4459) can be explained as ΞcD¯∗ molecular state and the quantum numbers are 0(21)−. In addition, we also find other molecular states ΞcD¯, Ξc∗D¯ and Ξc′D¯ ∗. It is worth mentioning that ΞcD¯ ∗ can form a two-peak structure from states in system 0(21)− and 0(23)−. The decay width of all molecular states is given with the help of real scaling method. These hidden-charm pentaquark states is expected to be further verified in future experiments. Copyright © 2021, The Authors. All rights reserved.

关键词： Quantum theory

Y (4626) in a chiral constituent quark model

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arXiv 2019年

作者： Tan, Yue Ping, Jialun Department of Physics Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal University Nanjing210023 China

Recently, Belle Collaboration reported a new exotic state Y (4620) with mass at 4625.9 MeV in the positronium annihilation process. Inspired by experiment, we study the tetraquark system css ¯ c¯ with quantum numbers JP = 1− in the framework of chiral constituent quark model with the help of Gaussian expansion method. Two structures, diquark-antidiquark and meson-meson, with all possible color and spin configurations are considered. The result shows that no bound state can be formed. To investigate the possible resonance states, the real scaling method is employed. Several resonance states with energies 4354, 4408, 4469, 4497 and 4531 MeV, are proposed. Taking into account the errors in calculating the qq¯ mesons, the system errors in the calculation of four-quark system are around 60∼ 100 MeV. The resonance with energy 4531 MeV is possible the candidate of the newly found state Y (4620). Copyright © 2019, The Authors. All rights reserved.

关键词： Hadrons

Impacts of major volcanic eruptions over the past two millennia on both global and Chinese climates:A review

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Science China Earth Sciences 2024年第1期67卷 61-78页

作者： Weiyi SUN Deliang CHEN Guonian LÜ Liang NING Chaochao GAO Renhe ZHANG Bin WANG Jian LIU Key Laboratory for Virtual Geographic Environment Ministry of EducationState Key Laboratory Cultivation Base of Geographical Environment Evolution of Jiangsu ProvinceJiangsu Center for Collaborative Innovation in Geographical Information Resource Development and ApplicationSchool of Geography ScienceNanjing Normal UniversityNanjing 210023China Regional Climate Group Department of Earth SciencesUniversity of GothenburgGothenburg 40530Sweden College of Environmental and Resource Science Zhejiang UniversityHangzhou 310058China Department of Atmospheric and Oceanic Sciences&Institute of Atmospheric Sciences Fudan UniversityShanghai 200437China Department of Atmospheric Sciences and Atmosphere-Ocean Research Center University of Hawaii at ManoaHonoluluHI 96825USA Jiangsu Provincial Key Laboratory for Numerical Simulation of Large Scale Complex Systems School of Mathematical ScienceNanjing Normal UniversityNanjing 210023China Open Studio for the Simulation of Ocean-Climate-Isotope Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China

Major volcanic eruptions(MVEs)have attracted increasing attention from the scientific *** studies have explored the climatic impact of MVEs over the past two ***,proxy-based reconstructions and climate model simulations indicate divergent responses of global and China’s regional climates to ***,we used multiple data from observations,reconstructions,simulations,and assimilations to summarize the historical facts of MVEs,the characteristics and mechanisms of their climatic impact,and directions for future *** reviewed volcanic datasets and determined intensive MVE periods;these periods corresponded to the years 530–700,1200‒1460,and 1600‒1840 *** tropical MVEs,a substantial cooling effect is observed throughout the globe and China on the interannual-interdecadal time scales but an inconsistent cooling magnitude is detected between reconstructions and *** the first summer after tropical MVEs,a decrease in global and monsoonal precipitation is *** reconstructions and simulations,an increased precipitation is seen for the Yangtze River Basin,while large uncertainties in precipitation changes are present for other regions of *** drought can be induced by frequent eruptions and volcanism superimposed on low solar irradiation and internal *** affect climate directly through the radiative effect and indirectly by modulating internal variability,such as the El Niño‒Southern Oscillation(ENSO)and Atlantic Multidecadal Oscillation(AMO).However,changes in the phase,amplitude,and periodicity of ENSO and AMO after MVEs and the associated mechanisms remain controversial,which could account for model-reconstruction ***,other internal variability,uncertainties in reconstruction methods and aerosol‒climate models,and climate background may also induce model-reconstruction *** gaps and directions for future research are also discussed.

关键词： Major volcanic eruption Climate variability Mechanism Past two millennia Internal variability

QQqq in a chiral constituent quark model

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arXiv 2020年

作者： Tan, Yue Lu, Weichang Ping, Jialun Dept. of Physics and Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal University Nanjing210023 China

Inspired by Ξccreported by LHCb Collaboration and X(5568) reported by D0 Collaboration, the QQqq (Q = c, b, q = u, d) tetraquark states, are studied in the present work. With the help of Gaussian expansion method, two structures, diquark-antiquark and meson-meson, with all possible color configurations are investigated systematically in a chiral quark model to search for the possible stable states. The results show that there is no bound state in the isovector QQqq system, while there are rather deep bound states in the isoscalar bbqq, ccqq and bcqq systems. Mixing two structures of diquark-antidiquark and meson-meson can introduce more attractions and convert some unbound isoscalar states into shallow bound states. The large mass of the heavy quark is beneficial to the formation of the bound state. The separations between quarks are calculated to unravel the spacial structure of the system. Copyright © 2020, The Authors. All rights reserved.

关键词： Hadrons

Strength of the North African monsoon in the Last Interglacial and under future warming

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Atmospheric and Oceanic Science Letters 2023年第3期16卷 20-26页

作者： Jiazhi He Weiyi Sun Jing Wang Bin Wang Jian Liu Key Laboratory for Virtual Geographic Environment Ministry of EducationState Key Laboratory Cultivation Base of Geographical Environment Evolution of Jiangsu ProvinceJiangsu Center for Collaborative Innovation in Geographical Information Resource Development and ApplicationSchool of Geography ScienceNanjing Normal UniversityNanjingChina Department of Atmospheric Sciences and AtmosphereOcean Research Center University of Hawaii at ManoaHonoluluHIUA Jiangsu Provincial Key Laboratory for Numerical Simulation of Large Scale Complex Systems School of Mathematical ScienceNanjing Normal UniversityNanjingChina Open Studioforthe Simulationof Ocean-Climate-Isotope Qingdao National Laboratoryfor Marine Science and TechnologyQingdaoChina

与人为强迫引起的全球变暖相比,末次间冰期是轨道强迫引起的过去80万年来最暖的一个间冰期,但鲜有人研究末次间冰期中北非季风的响应.因此,本文基于CMIP6多模式模拟结果对比研究了末次间冰期和SSP5-8.5情景下北非季风的响应,发现末次间... 详细信息

与人为强迫引起的全球变暖相比,末次间冰期是轨道强迫引起的过去80万年来最暖的一个间冰期,但鲜有人研究末次间冰期中北非季风的响应.因此,本文基于CMIP6多模式模拟结果对比研究了末次间冰期和SSP5-8.5情景下北非季风的响应,发现末次间冰期下北非季风平均降水及其降水变率均远大于SSP5-8.5情景下的结果.轨道强迫导致的北大西洋暖于南大西洋增加了北非季风环流和平均降水,同时,南北大西洋海温梯度变化通过增强热带北大西洋的海气相互作用增大了海温梯度和撒哈拉低压的变率,从而增强了北非季风降水变率.

关键词：北非季风降水变率末次间冰期全球变暖

The global existence and large time behavior of smooth compressible fluid in an infinitely expanding ball, I: 3D Euler equations

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arXiv 2017年

作者： Xu, Gang Yin, Huicheng Faculty of Science Jiangsu University Zhenjiang Jiangsu212013 China School of Mathematical Sciences Jiangsu Provincial Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal University Nanjing210023 China

We concern with the global existence and large time behavior of compressible fluids (including the inviscid gases, viscid gases, and Boltzmann gases) in an infinitely expanding ball. Such a problem is one of the interesting models in studying the theory of global smooth solutions to multidimensional compressible gases with time dependent boundaries and vacuum states at infinite time. Due to the conservation of mass, the fluid in the expanding ball becomes rarefied and eventually tends to a vacuum state meanwhile there are no appearances of vacuum domains in any part of the expansive ball, which is easily observed in finite time. In this paper, as the first part of our three papers, we will confirm this physical phenomenon for the compressible inviscid fluids by obtaining the exact lower and upper bound on the density function. Copyright © 2017, The Authors. All rights reserved.

关键词： Euler equations

simulation of Centennial-scale Drought Events over Eastern China during the Past 1500 Years

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Journal of Meteorological Research 2017年第1期31卷 17-27页

作者： Weiyi SUN Jian LIU Zhiyuan WANG key laboratory for virtual geographic environment(nanjing normal university) ministry of educationstate key laboratory cultivation base of geographical environment evolution(jiangsu province)School of Geography ScienceNanjing Normal UniversityNanjing 210023 Jiangsu Provincial Key Laboratory for Numerical Simulation of Large Scale Complex Systems School of Mathematical ScienceNanjing Normal UniversityNanjing 210023 Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023

The characteristics and causes of centennial-scale drought events over eastern China during the past 1500 years were explored based on simulations of the Community Earth system Model （CESM）. The results show that centenni- al-scale drought events over eastern China occurred during the periods of 622-735 （Drought period 1, D1） and 1420-1516 （Drought period 2, D2） over the past 1500 years, which is comparable with climate proxy data. In D1, the drought center occurred in northern China and the Yangtze River valley; however, in southern China, precipitation was much more than usual. In D2, decreased precipitation was found across almost the whole region of eastern China. The direct cause of these two drought events was the weakened East Asian summer monsoon, and the specif- ic process was closely linked to the air-sea interaction of the Indo-Pacific Ocean. In DI, regions of maximum cool- ing were observed over the western Pacific, which may have led to anomalous subsidence, weakening the Walker cir- culation, and reducing the northward transport of water vapor. Additionally, upward motion occurred over southern China, strengthening convection and increasing precipitation. In D2, owing to the decrease in the SST, subsidence dominated the North Indian Ocean, blocking the low-level cross-equatorial flow, enhancing the tropical westerly an- omalies, and reducing the northward transport of moisture. Additionally, descending motion appeared in eastern China, subsequently decreasing the precipitation over the whole region of eastern China. The anomalous cooling of the Indo-Pacific Ocean SST may have been caused by the persistently low solar irradiation in D1; whereas, in D2, this characteristic may have been influenced not only by persistently low solar irradiation, but frequent volcanic erup- tions too.

关键词： CESM centennial-scale drought eastern China East Asian summer monsoon

The global existence and large time behavior of smooth compressible fluid in an infinitely expanding ball, III: The 3-D Boltzmann equation

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arXiv 2017年

作者： Yin, Huicheng Zhao, Wenbin School of Mathematical Sciences Jiangsu Provincial Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal University Nanjing210023 China Department of Mathematics and IMS Nanjing University Nanjing210093 China

This paper is a continuation of the works in [34] and [36], where the authors have established the global existence of smooth compressible flows in infinitely expanding balls for inviscid gases and viscid gases, respectively. In this paper, we are concerned with the global existence and large time behavior of compressible Boltzmann gases in an infinitely expanding ball. Such a problem is one of the interesting models in studying the theory of global smooth solutions to multidimensional compressible gases with time dependent boundaries and vacuum states at infinite time. Due to the conservation of mass, the fluid in the expanding ball becomes rarefied and eventually tends to a vacuum state meanwhile there are no appearances of vacuum domains in any part of the expansive ball, which is easily observed in finite time. In the present paper, we will confirm this physical phenomenon for the Boltzmann equation by obtaining the exact lower and upper bound on the macroscopic density function. Copyright © 2017, The Authors. All rights reserved.

关键词： Boltzmann equation