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Testing B-violating signatures from exotic instantons in future colliders

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Chinese Physics C 2017年第9期41卷 19-26页

作者： Andrea Addazi xian-Wei kang Maxim Yu. Khlopov Dipartimento di Fisica Universith di L'Aquila 67010 Coppito AQ and LNGS Laboratori Nazionali del Gran Sasso 67010 Assergi AQ Institute of Physics Academia Sinica Taipei 115 Institute for Advanced Simulation Jiilich Center for Hadron Physics and Institut fiir Kernphysik Forschungszentrum Jiilich D-52425 Jiilich Centre for Cosmoparticle Physics Cosmion National Research Nuclear University MEPHI (Moscow Engineering Physics Institute) Kashirskoe Sh. 31 Moscow 115409 APC laboratory 10 rue Alice Domon et Leonie Duquet 75205 Paris Cedex 13

We discuss possible implications of exotic stringy instantons for baryon-violating signatures in future colliders. In particular, we discuss high-energy quark collisions and A- transitions. In principle, the A-A process can be probed by high-luminosity electron-positron colliders. However, we find that an extremely high luminosity is needed in order to provide a （somewhat） stringent bound compared to the current data on NN→ππ,KK. On the other hand, （exotic） instanton-induced six-quark interactions can be tested in near future high-energy colliders beyond LHC, at energies around 20-100 TeV. The Super proton-proton Collider （SppC） would be capable of such measurement given the proposed energy level of 50-90 TeV. Comparison with other channels is made. In particular, we show the compatibility of our model with neutron-antineutron and NN→ππ, KK bounds.

关键词： CEPC SppC exotic instanton baryon number violation

Two-body nonleptonic decays of the heavy mesons in the factorization approach

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Frontiers of physics 2023年第6期18卷 107-126页

作者： Shuo-Ying Yu xian-Wei kang V.O.Galkin Key Laboratory of Beam Technology of the Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China Federal Research Center“Computer Science and Control” Russian Academy of SciencesVavilov Street 40119333 MoscowRussia

In the framework of the factorization approach we calculate the branching fractions of 100 two-body nonleptonic decay channels in total,including 44 channels of the charm meson decays and 56 channels of the bottom meson *** charm meson decays,we test and confirm the previous observation that taking the limit for the number of colors N→∞significantly improves theoretical *** bottom meson decays,the penguin contributions are included in *** an essential input,we employ the weak decay form factors obtained in the framework of the relativistic quark model based on the quasi-potential *** form factors have well been tested by calculating observables in the semileptonic D and B meson decays and confronting obtained results with experimental *** general,the predictions for the nonleptonic decay branching fractions are ***,for a quantitative calculation it is necessary to account for a more subtle effects of the final-state interaction.

关键词： form factor quark model nonleptonic decay factorization method

Erosion-corrosion and its mitigation on the internal surface of the expansion segment of N80 steel tube

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International Journal of Minerals,Metallurgy and Materials 2021年第1期28卷 98-110页

作者： Tan Shang xian-kang Zhong Chen-feng Zhang Jun-ying Hu Bálint Medgyes State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu 610500China Department of Electronics Technology Budapest University of Technology and EconomicsBudapest H-1111Hungary

We investigated erosion-corrosion(E-C) and its mitigation on the internal surface of the expansion segment of N80 steel tube in a loop system using array electrode technique, weight-loss measurement, computational-fluid-dynamics simulation, and surface characterization *** results show that high E-C rates can occur at locations where there is a high flow velocity and/or a strong impact from sand particles, which results in different E-C rates at various ***, it can be expected that localized corrosion often occurs in such *** E-C rate at each location in the expansion segment can be significantly mitigated with an imidazoline derivative inhibitor, as the resulting inhibitor layer significantly impedes the electrochemical reaction ***, we found that this inhibitor layer could not effectively reduce the difference in the erosion rates at different locations on the internal surface of the expansion *** means that localized corrosion can still occur at the expansion segment despite the presence of the inhibitor.

关键词： erosion-corrosion expansion segment array electrode technique inhibitor localized corrosion

A Study on the Correlation Between Poles and Cuts in ππ Scattering

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Communications in Theoretical Physics 2019年第11期71卷 1309-1318页

作者： Ling-Yun Dai xian-Wei kang Tao Luo School of Physics and Electronics Hunan University College of Nuclear Science and Technology Beijing Normal University Key Laboratory of Nuclear Physics and Ion-beam Application(MOE) and Institute of Modern Physics Fudan University Helmholtz Institut für Strahlen-und Kernphysik and Bethe Center for Theoretical Physics Universit?t Bonn Institute for Advanced Simulation Institut f¨ur Kernphysik and Jülich Center for Hadron Physics Forschungszentrum Jülich

In this paper we propose a dispersive method to describe two-body scattering with unitarity imposed. This approach is applied to elastic ππ scattering. The amplitudes keep single-channel unitarity and describe the experimental data well, and the low-energy amplitudes are consistent with that of chiral perturbation theory. The pole locations of the σ, f0(980), ρ(770) and f2(1270) and their couplings to ππ are obtained. A virtual state appearing in the isospin-two S-wave is confirmed. The correlations between the left(and right) hand cut and the poles are discussed. Our results show that the poles are more sensitive to the right hand cut rather than the left hand cut. The proposed method could be used to study other two-body scattering processes.

关键词： dispersion relations partial-wave analysis chiral lagrangian meson production

Study of crust-mantle transitional zone along the northeast margin of Qinghai-Xizang plateau

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Acta Seismologica Sinica(English Edition) 2004年第2期17卷 144-151页

作者： LAI Xiao-ling(赖晓玲) ZHANG xian-kang(张先康) FANG Sheng-ming(方盛明) Geophysical Exploration Center China Earthquake Administration Zhengzhou 450002 China Geophysical Exploration Center China Earthquake Administration Zhengzhou 450002 China Geophysical Exploration Center China Earthquake Administration Zhengzhou 450002 China

This study deals with complexity, frequency spectrum and velocity model of the crust-mantle transitional zone in different tectonic units along the northeast margin of Qinghai-Xizang plateau, based on PmP waveform data from two deep seismic sounding profiles passing through the area. It reveals that Moho has stable tectonic features in Ordos and Lingzhong basins, where crust and mantle are coupled as first-order discontinuity. Moho shows obvious signs of activity in Haiyuan seismic region and in the contact zone between Bayanhar block and Qaidam block. Crust and mantle in these two areas are coupled as complicated crust-mantle transitional zone consisting of multiple laminae with alternate high and low velocities, totaling 20 km in thickness. The difference between Moho of different tectonic units reflects heterogeneity of the coupled crust-mantle zone; the difference between fine structures of Haiyuan seismic region and Maqin fault zone reflects different deep material composition of the two continent-continent collision zones and the interaction between blocks.

关键词： crust-mantle transitional zone tectonic units Haiyuan seismic region Maqin fault zone

Controllable four-wave mixing based on quantum dot-cavity coupling system

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Communications in Theoretical Physics 2021年第5期73卷 25-32页

作者： Hong-Wu Xing Bin Chen Li-Li Xing Jian-Bin Chen Hai-Bin Xue kang-xian Guo Department of Physics College of Physics and OptoelectronicsTaiyuan University of TechnologyTaiyuan 030024China Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of Education and Shanxi ProvinceTaiyuan 030024China Department of Physics School of Physics and Materials ScienceGuangzhou UniversityGuangzhou 510006China

We theoretically study the four-wave mixing(FWM)response in a quantum dot-cavity coupling system,where a two-level quantum dot(QD)is placed in an optical cavity while the cavity mode is coupled to the nanomechanical resonator via radiation *** influences of the QD-cavity coupling strength,the Rabi coupling strength of the QD,and the power of the pump light on the FWM intensity are mainly *** numerical results show that the FWM intensity in this hybrid system can be significantly enhanced by increasing the QD-cavity coupling *** addition,the FWM intensity can be effectively modulated by the Rabi coupling strength and the pump ***,the effects of the cavity decay rate and the cavitypump detuning on the FWM signal are also *** obtained results may have potential applications in the fields of quantum optics and quantum information science.

关键词： four-wave mixing quantum dot-cavity coupling system input-output relation

RareΛb→Λl+l−decay in the Bethe-Salpeter equation approach

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Chinese Physics C 2020年第8期44卷 78-87页

作者： Liang-Liang Liu xian-Wei kang Zhen-Yang Wang Xin-Heng Guo College of Physics and Information Engineering Shanxi Normal UniversityLinfen 041004China Physics Department Ningbo UniversityZhejiang 315211China College of Nuclear Science and Technology Beijing Normal UniversityBeijing 100875China

We study the rare decaysΛb→Λl+l−(l=e,μ,τ)in the Bethe-Salpeter equation *** find that the branching ratio is Br(Λb→Λμ^+μ^−)×10^6=1.051∼1.098 in our *** result agrees with the experimental data *** the same parametric region,we find that the branching ratio is Br(Λb→Λe^+e^−(τ^+τ^−))×10^6=0.252∼0.392(0.286∼0.489).

关键词： charmonium decay width lattice QCD

Effects of hydrostatic pressure and temperature on the nonlinear optical properties of semiparabolic plus semi-inverse squared quantum wells

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Communications in Theoretical Physics 2021年第8期73卷 139-145页

作者： Guo-Liang Xu Zi Zhen Yi-Sheng Shi kang-xian Guo E Feddi Jian-Hui Yuan Zhi-Hai Zhang School of Physics and Electronics Yancheng Teachers UniversityYancheng 224002China Department of Physics College of Physics and Electronic EngineeringGuangzhou UniversityGuangzhou 510006China Laboratoire de la matiere condensee et Sciences Interdisciplinaires(LAMCScI) Group of Optoelectronic of Semiconductors and NanomaterialsENSETMohammed V University in RabatMorocco Laboratory of Biomedical Photonics and Engineering Guangxi Medical UniversityNanning 530021China

In this study,the effects of hydrostatic pressure and temperature on nonlinear optical rectification(OR),second-harmonic generation(SHG),third-harmonic generation(THG)and the linear,nonlinear,and total optical absorption coefficients(OACs)of a semiparabolic plus semi-inverse squared quantum well(QW)are theoretically *** results show that hydrostatic pressure and temperature have significant effects on the optical properties of semiparabolic plus semi-inverse squared QWs,and that the energy levels and magnitudes of the resonant peaks of OR,SHG,THG,and the total OACs vary according to the shape of the limiting potential,the hydrostatic pressure,and the *** is easily seen that the peak positions of the resonant peaks of OR,SHG,THG,and the total OACs in the semiparabolic plus semi-inverse squared QW show a red shift with increasing hydrostatic pressure,but a blue shift with increasing ***,the magnitude and position of the resonant peaks of OR,SHG,THG,and the total OACs can be adjusted by changing the hydrostatic pressure and the temperature,which promise a new degree of freedom in the tunability of various electro-optical devices.

关键词： Quantum well Optical properties Hydrostatic pressure Temperature

Controllable four-wave mixing response in a dual-cavity hybrid optomechanical system

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Chinese Physics B 2021年第5期30卷 406-411页

作者： Lei Shang Bin Chen Li-Li Xing Jian-Bin Chen Hai-Bin Xue kang-xian Guo Department of Physics College of Physics and OptoelectronicsTaiyuan University of TechnologyTaiyuan 030024China Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of Education and Shanxi ProvinceTaiyuan 030024China Department of Physics School of Physics and Material ScienceGuangzhou UniversityGuangzhou 510006China

We systematically investigate the four-wave mixing(FWM)spectrum in a dual-cavity hybrid optomechanical system,which is made up of one optical cavity with an ensemble of two-level atoms and another with a mechanical *** this work,we propose that the hybrid dual-cavity optomechanical system can be employed as a highly sensitive mass sensor due to the fact that the FWM spectrum generated in this system has a narrow spectral width and the intensity of the FWM can be easily tuned by controlling the coupling strength(cavity-cavity,atom-cavity).More fascinatingly,the dual-cavity hybrid optomechanical system can also be used as an all-optical switch in view of the easy on/off control of FWM signals by adjusting the atom-pump detuning to be positive or *** proposed schemes have great potential applications in quantum information processing and highly sensitive detection.

关键词： four-wave mixing dual-cavity optomechanical system atomic ensemble