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Z boson decays Z → li±lj and Higgs boson decays h → li±lj with lepton flavor violation in a U(1) extension of the MSSM

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arXiv 2022年

作者： Wang, Yi-Tong Zhao, Shu-Min Wang, Tong-Tong Wang, Xi Long, Xin-Xin Ma, Jiao Feng, Tai-Fu Department of Physics Hebei University Baoding071002 China Key Laboratory of High-precision Computation and Application of Quantum Field Theory of Hebei Province Baoding071002 China Department of Physics Chongqing University Chongqing401331 China

U(1)XSSM is the extension of the minimal supersymmetric standard model (MSSM) and its local gauge group is SU(3)C × SU(2)L × U(1)Y × U(1)X. We study lepton flavor violating (LFV) decays Z → li±lj(Z → eµ, Z → eτ, and Z → µτ) and h → li±lj(h → eµ, h → eτ, and h → µτ), in this model. In the numerical results, the branching ratios of Z → li±lj are from 10−9 to 10−13 and the branching ratios of h → li±lj are from 10−3 to 10−9, which can approach the present experimental upper bounds. Based on the latest experimental data, we analyze the influence of different sensitive parameters on the branching ratio, and make reasonable predictions for future experiments. The main sensitive parameters and LFV sources are the non-diagonal elements corresponding to the initial and final generations of leptons, which can be seen from the numerical analysis. Copyright © 2022, The Authors. All rights reserved.

关键词： Fractals

ηc2(1D2) and its electromagnetic decays

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arXiv 2024年

作者： Du, Xin-Yao Pei, Su-Yan Li, Wei Jia, Man Li, Qiang Wang, Tianhong Wang, Bo Wang, Guo-Li Department of Physics Hebei University Baoding071002 China Hebei Key Laboratory of High-precision Computation and Application of Quantum Field Theory Baoding071002 China Hebei Research Center of the Basic Discipline for Computational Physics Baoding071002 China School of Physical Science and Technology Northwestern Polytechnical University Xi’an710129 China School of Physics Harbin Institute of Technology Harbin150001 China

The spin-singlet state ηc2(1D2) has not been discovered in experiment and it is the only missing low-excited D-wave charmonium, so in this paper, we like to study its properties. Using the Bethe-Salpeter equation method, we obtain its mass as 3828.2 MeV and its electromagnetic decay widths as Γ[ηc2(1D) → hc(1P)γ] = 284 keV, Γ[ηc2(1D) → J/ψγ] = 1.04 keV, Γ[ηc2(1D) → ψ(2S)γ] = 3.08 eV, and Γ[ηc2(1D) → ψ(3770)γ] = 0.143 keV. Considering the strong decay widths are estimated to be Γ(ηc2(1D) → ηcππ) = 144 keV and Γ(ηc2(1D) → gg) = 46.1 keV, we obtain the total decay width of 475 keV for ηc2(1D), and point out that the full width is very sensitive to the mass Mηc2. In our calculation, the emphasis is put on the relativistic corrections. Our results show that ηc2 → hcγ is the nonrelativistic E1 transition dominated E1 + M2 + E3 decay, and ηc2 → ψγ is the M1 + E2 + M3 + E4 decay but the relativistic E2 transition contributes the most. Copyright © 2024, The Authors. All rights reserved.

关键词： Relativity

The origin of the 95 GeV excess in the flavor-dependent U(1)X model

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arXiv 2024年

作者： Ge, Zhao-Feng Niu, Feng-Yan Yang, Jin-Lei CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences Beijing100190 China School of Physical Sciences University of Chinese Academy of Sciences Beijing100049 China Department of Physics Hebei University Baoding071002 China Key Laboratory of High-Precision Computation Application of Quantum Field Theory of Hebei Province Baoding071002 China Research Center for Computational Physics of Hebei Province Baoding071002 China

This study investigates the excesses observed in the CMS diphoton and ditau data around 95 GeV within the framework of the flavor-dependent U(1)X model. The model introduces a singlet scalar to explain the nonzero neutrino masses. This newly introduced Higgs interacts directly with the quark sector, motivated by the aim to explain the flavor numbers of the fermion sector. Additionally, it undergoes mixing with the SM-like Higgs boson. The study suggests that designating this singlet Higgs state in this model as the lightest Higgs boson holds great potential for explaining the excesses around 95 GeV. In the calculations, we maintained the masses of the lightest and next-to-lightest Higgs bosons at around 95 GeV and 125 GeV respectively. It was found that the theoretical predictions on the signal strengthes µ(h95)γγ, µ(h95)ττ in the flavor-dependent U(1)X model can be fitted well to the excesses observed at CMS. Copyright © 2024, The Authors. All rights reserved.

关键词： Bosons

Partial wave effects in the heavy quarkonium radiative electromagnetic decays

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arXiv 2022年

作者： Pei, Su-Yan Li, Wei Liu, Ting-Ting Han, Meng Wang, Guo-Li Wang, Tian-Hong Department of Physics and Technology Hebei University Baoding071002 China Key Laboratory of High-precision Computation Application of Quantum Field Theory of Hebei Province Baoding China School of Physics Harbin Institute of Technology Harbin150001 China

In a previous paper [1], it was pointed out that the wave functions of all particles are not pure waves, besides the main partial waves, they all contain other partial waves. It is very interesting to know what role these different partial waves play in particle transitions. Therefore, by using the Bethe-Salpeter equation method, we study the radiative electromagnetic decays ψ → γχcJ and Υ → γχbJ (J = 0, 1, 2). We find that for the S and P wave dominated states, like the ψ(2S), Υ(2S), χcJ (1P), and χbJ (1P) etc., the dominant S and P waves provide main and nonrelativistic contrition to the decays;other partial waves mainly contribute to the relativistic correction. For the states like the ψ(1D), Υ(2D), χc2(1F), and χb2(1F) etc., they are the S − P − D mixing state dominated by D wave or the P − D − F mixing state dominated by F wave. Large decay widths are found in the transitions ψ(2D) → χc2(1F), Υ(1D) → χbJ (1P), and Υ(2D) → χbJ (2P) etc., which may be helpful to study the missing states χc2(1F), Υ(1D), and Υ(2D). Copyright © 2022, The Authors. All rights reserved.

关键词： Wave functions

W boson mass in the NP models with extra U(1) gauge group

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arXiv 2023年

作者： Yang, Jin-Lei Ge, Zhao-Feng Yang, Xiu-Yi Cui, Sheng-Kai Feng, Tai-Fu Department of Physics Hebei University Baoding071002 China Key Laboratory of High-precision Computation and Application of Quantum Field Theory of Hebei Province Baoding071002 China CAS Key Laboratory of Theoretical Physics School of Physical Sciences University of Chinese Academy of Sciences Beijing100049 China School of science University of Science and Technology Liaoning Anshan114051 China

The precise measurement of the W boson mass is closely related to the contributions of new physics (NP), which can significantly constrain the parameter space of NP models, particularly those with an additional U(1) local gauge group. The inclusion of a new Z' gauge boson and gauge couplings in these models can contribute to the oblique parameters S, T, U and the W boson mass at tree level. Taking into account the effects of kinetic mixing, in this study we calculate and analyze the oblique parameters S, T, U and the W boson mass in such NP models. It is found that the kinetic mixing effects can make significant contributions to the W boson mass, and these contributions can be eliminated by redefining the gauge boson fields through eliminating the neutral currents involving charged leptons, if the leptonic Yukawa couplings are invariant under the extra U(1) local gauge group, even with nonzero kinetic mixing effects. © 2023, CC BY.

关键词： Bosons

Study some two loop contribution to muon anomalous MDM in the N-B-LSSM

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arXiv 2024年

作者： Han, Xing-Yu Zhao, Shu-Min Ruan, Long Wang, Xi Dong, Xing-Xing Department of Physics Hebei University Baoding071002 China Hebei Key Laboratory of High-Precision Computation and Application of Quantum Field Theory Baoding071002 China Hebei Research Center of the Basic Discipline for Computational Physics Baoding071002 China Departamento de Fisica CFTP Instituto Superior Técnico Universidade de Lisboa Av.Rovisco Pais 1 Lisboa1049-001 Portugal

It is well known that the muon magnetic dipole moment (MDM) has close relation with the new physics (NP) in the development of the Standard Model (SM). Combined with the Fermilab National Accelerator laboratory (FNAL) and the Brookhaven National laboratory (BNL) E821 result, the departure from the SM prediction is about 5.0 σ. We study the electroweak corrections from several type two-loop SUSY diagrams and the virtual SUSY particles include chargino, neutralino, scalar lepton and scalar neutrino. Based on the latest experimental constraints, we study the muon anomalous MDM under the next to the minimal supersymmetric extension of the SM with local B-L gauge symmetry (N-B-LSSM). The abundant numerical results verify that tan β, Te22, M2L, M2e, MBB′ play an important role in muon anomalous MDM. M2e, tan β and Te22 are sensitive parameters to muon anomalous MDM. From the data obtained in all the figures of the numerical results, most of the values of aNBLµ are in 2σ interval, which can compensate the departure between the experiment data and the SM prediction. Copyright © 2024, The Authors. All rights reserved.

关键词： Electric dipole moments

Spectrum of the molecular tetraquarks: Unraveling the Tcs0(2900) and Tcs¯0a(2900)

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Physical Review D 2024年第3期109卷 034027-034027页

作者： Bo Wang Kan Chen Lu Meng Shi-Lin Zhu College of Physics Science & Technology Hebei University Baoding 071002 China Hebei Key Laboratory of High-precision Computation and Application of Quantum Field Theory Baoding 071002 China Hebei Research Center of the Basic Discipline for Computational Physics Baoding 071002 China School of Physics Northwest University Xi’an 710127 China Institut für Theoretische Physik II Ruhr-Universität Bochum D-44780 Bochum Germany School of Physics and Center of High Energy Physics Peking University Beijing 100871 China

We relate the interactions of the D¯(*)K* and D(*)K* systems to those of D(*)D(*) and D(*)D¯(*) respectively, considering the residual strong interactions at the near-threshold energy is too weak to excite the strange quarks inside the hadrons. We propose an effective model to describe the low-energy S-wave interactions that are undertaken by the light u, d quarks between two separated heavy hadrons. We find that the existence of molecules in the heavy-(anti)heavy sectors will naturally lead to the emergence of molecular states in D¯(*)K* and D(*)K* systems. The recently observed Tcs0(2900) and Tcs¯0a(2900) can be well identified as the 0(0+) and 1(0+) partners of Tcc(3875) and Zc(3900) in the charmed strange sector, respectively. We also predict their members under the heavy (c and s) quark symmetry and SU(2) flavor symmetry. Most of them are very good molecule candidates, for example, (i) the 0(1+) states in D*D*, D¯K*, D¯*K*; (ii) the 0(+)(2+(+)) states in D*D¯*, D¯*K*, D*K*; (iii) the 1−(0++) state in D*D¯* and 1(1+) state in D*K*. The 0+(0++) state in DD¯ and the 0(1+) state in DK* might also exist as virtual states, and the 0(1+) DK* can serve as a key to infer the existence of 0+(0++) DD¯. The Dsπ invariant mass spectrum of Tcs¯0a(2900) is also studied within the coupled-channel approach, and the molecular interpretation of Tcs¯0a(2900) is consistent with the experimental data. Searching for the predicted states in experiments is crucial to discriminate the different pictures for interpreting these near-threshold exotica.

关键词： Hadron-hadron interactions Multiquark bound states Phenomenology Quark model

Double pole structures of X1(2900) as the P-wave D¯*K* resonances

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Physical Review D 2024年第11期110卷 114003-114003页

作者： Jun-Zhang Wang Zi-Yang Lin Bo Wang Lu Meng Shi-Lin Zhu School of Physics and Center of High Energy Physics Peking University Beijing 100871 China School of Physics Peking University Beijing 100871 China College of Physics Science and Technology Hebei University Baoding 071002 China Hebei Key Laboratory of High-precision Computation and Application of Quantum Field Theory Baoding 071002 China Hebei Research Center of the Basic Discipline for Computational Physics Baoding 071002 China Institut für Theoretische Physik II Ruhr-Universität Bochum D-44780 Bochum Germany

We reveal the double pole structures of the manifestly exotic tetraquark state X1(2900) in the scenario of P-wave D¯*K* dimeson resonance. We find that the observed enhancement signal associated with X1(2900) in B+→D+D−K+ by LHCb contains two P-wave poles denoted as Tcs1−(2900) and Tcs1−′(2900), respectively. After considering the channel couplings among the D¯K, D¯*K, D¯K* and D¯*K* and the width of the K* meson, the masses and widths of the S-wave pole Tcs0+(2900) and two P-wave poles Tcs1−(2900) and Tcs1−′(2900) coincide with those of the X0(2900) and X1(2900) remarkably, which provides strong support for identifying X0(2900) and X1(2900) as D¯(*)K(*) dimeson states. Furthermore, we extensively calculate all S-wave and P-wave D¯(*)K(*) systems up to J=3 and predict four new isoscalar charmed-strange dimeson-type tetraquark states: an S-wave state Tcs1+(2900) with quantum number JP=1+, three P-wave states Tcs1−(2760) with JP=1−, Tcs0−(2760) with JP=0− and Tcs2−(2900) with JP=2−. These near-threshold poles can be searched for at LHCb, Belle II and BESIII.

关键词： Strong interaction

A new parametrization of Hubble function and Hubble tension

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arXiv 2024年

作者： He, Tong-Yu Yin, Jia-Jun Wang, Zhen-Yu Han, Zhan-Wen Yang, Rong-Jia College of Physics Science and Technology Hebei University Baoding071002 China Yunnan Observatories Chinese Academy of Sciences Kunming650216 China Hebei Key Lab of Optic-Electronic Information and Materials Hebei University Baoding071002 China National-Local Joint Engineering Laboratory of New Energy Photoelectric Devices Hebei University Baoding071002 China Key Laboratory of High-pricision Computation and Application of Quantum Field Theory of Hebei Province Hebei University Baoding071002 China

We present a new parameterized Hubble function and employ observational data from Hubble, Pantheon, and Baryon Acoustic Oscillations to constrain model parameters. The proposed method is thoroughly validated against these datasets, demonstrating a robust fit to the observational data. The obtained best-fit values are H0 = 67.5+1−1.36 km s−1Mpc−1, Ωm0 = 0.2764 ± 0.0094, and α = 0.33 ± 0.22, consistent with the Planck 2018 results, highlighting the existence of Hubble tension. © 2024, CC BY-NC-SA.

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