Zhaotong University
By employing the Coulomb proximity potential model (CPPM) in conjunction with 22 distinct proximity potential models, we investigated the temperature dependence and the effects of proton number and neutron number on the diffusion parameters that determine the {\alpha}-decay half-lives of superheavy nuclei. The results indicate that the Prox.77-3 T-DEP proximity potential model yields the best performance, with the lowest root mean square deviation ({\sigma}=0.515), reflecting a high consistency with experimental data. In contrast, Bass77, AW95, Ngo80, and Guo2013 display larger deviations. The inclusion of temperature dependence significantly improves the accuracy of models such as Prox.77-3, Prox.77-6, and Prox.77-7. The -decay half-lives of 36 potential superheavy nuclei were further predicted using the five most accurate proximity potential models and Ni's empirical formula, with the results aligning well with experimental data. These predictions underscore the high reliability of the CPPM combined with proximity potential models in the theoretical calculation of {\alpha}-decay half-lives of superheavy nuclei, offering valuable theoretical insights for future experimental investigations of superheavy nuclei.
We investigate the global structure of the Gauged Two-Higgs-Doublet Model (G2HDM), a framework that extends the Standard Model by introducing a dark sector governed by the gauge symmetry U(1)X×SU(2)HU(1)_X \times SU(2)_H. The full gauge symmetry of the theory, including the visible sector, is given by the universal covering group $\tilde{G} = U(1)_Y \times SU(2)_L \times SU(3)_C \times U(1)_X \times SU(2)_H.However,thetruegaugegroupmayinsteadbeaquotient. However, the true gauge group may instead be a quotient G = \tilde{G} / \Gamma,where, where \Gammaisthecenterof is the center of \tilde{G}$ or a subgroup thereof, leading to different global structures that cannot be distinguished by local experiments.We explore the physical implications of these global structures, analyzing their effects on Wilson, 't Hooft, and dyonic line operators, as well as the periodicity of the CP-violating θ\theta-angles associated with each group factor. Furthermore, we determine the minimal electric and magnetic charges that arise after electroweak symmetry breaking, highlighting their dependence on the choice of Γ\Gamma. These findings provide a systematic characterization of the G2HDM's global properties and their potential phenomenological consequences.
In the Coulomb and Proximity Potential Model (CPPM) framework, we have investigated the cluster radioactivity and alpha decay half-lives of superheavy nuclei. We study 22 different versions of proximity potential forms that have been proposed to describe proton radioactivity, two-proton radioactivity, heavy-ion radioactivity, quasi-elastic scattering, fusion reactions, and other applications. The half-lives of cluster radioactivity and alpha decay of 41 atomic nuclei ranging from 221Fr to 244Cm were calculated, and the results indicate that the refined nuclear potential named BW91 is the most suitable proximity potential form for the cluster radioactivity and alpha decay of superheavy nuclei since the root-mean-square (RMS) deviation between the experimental data and the relevant theoretical calculation results is the smallest ({\sigma}= 0.841). By using CPPM, we predicted the half-lives of 20 potential cluster radioactivity and alpha decay candidates. These cluster radioactivities and alpha decays are energetically allowed or observable but not yet quantified in NUBASE2020.
We have integrated nonlocal effects with the Bayesian neural network (BNN) approach to enhance the prediction accuracy of α\alpha decay half-lives. The results indicate that incorporating nonlocal effects significantly impacts half-life calculations, while the BNN method substantially improves prediction accuracy and demonstrates strong extrapolation capabilities. Using Shapley Additive Explanations (SHAP), we conducted a quantitative comparison among the four input feature parameters in the BNN, revealing that the α\alpha decay energy QαQ_{\alpha} is the predominant contributor to T1/2T_{1/2}. Leveraging the BNN robust extrapolation capability, we predicted α\alpha decay half-lives for the isotopic chains (Z=118, 120), revealing a significant shell effect at N=184 of neutrons. Keywords: α\alpha decay, half-lives, nonlocal effects, Bayesian neural network, Coulomb and proximity potential model.
Based on Extreme Gradient Boosting (XGBoost) framework optimized via Bayesian hyperparameter tuning, we investigated the {\alpha}-decay energy and half-life of superheavy nuclei. By incorporating key nuclear structural features-including mass number, proton-to-neutron ratio, magic number proximity, and angular momentum transfer-the optimized model captures essential physical mechanisms governing α\alpha-decay. On the test set, the model achieves significantly lower mean absolute error (MAE) and root mean square error (RMSE) compared to empirical models such as Royer and Budaca, particularly in the low-energy region. SHapley Additive exPlanations (SHAP) analysis confirms these mechanisms are dominated by decay energy, angular momentum barriers, and shell effects. This work establishes a physically consistent, data-driven tool for nuclear property prediction and offers valuable insights into α\alpha-decay processes from a machine learning perspective.
Energy equipartition and the energy budget in the jet are import issues for the radiation mechanism of blazars. Early work predominantly concentrated on flat-spectrum radio quasars and a limited number of BL Lacertae objects (BL Lacs). In this paper, we compile 348 high-frequency peaked BL Lac objects (HBLs) based on the catalog of active galactic nuclei (4LAC-DR3) from Fermi-LAT, and employ \textit{JetSet} to fit the spectral energy distributions (SEDs) of these HBLs in the framework of the one-zone lepton model. We aim to determine whether the energy budget is reasonable and whether the energy equipartition is satisfied in HBLs. The results of the statistical analysis suggest that: (1) SEDs of HBLs can be reproduced well by using the one-zone lepton model; however it cannot achieve the energy equalization, and the relativistic electron energy density is far greater than the magnetic field energy density, Ue100UBU_{e} \gtrsim100 U_{B}; (2) the majority of the HBLs are located in the tcoolt_{cool}<tdynt_{dyn} region (where the horizontal coordinate represents the jet power of electrons, while the ordinate indicates the ratio between the dynamic time scale to the cooling timescale), and the jet kinetic power of HBLs is greater than the jet power of radiation; there is a very low radiation efficiency, we deduce that HBLs may have optically thin advection-dominated accretion flows; (3) the logϵB\log\epsilon_{B} of HBLs is less than zero, which indicates that the jet kinetic power of HBLs is not affected by Poynting flux; (4) the relationships with U_{e} >U_{Syn}\sim U_{B}, L_{e}\sim L_{p}>L_{B}\sim L_{rad} and \log\epsilon_{e}>0.5 are established. These relations indicate that most of the energy of HBLs is stored in the population of low-energy electrons.
We propose a scheme for realizing a deterministic two-photon C-Z gate based on variants of the two-photon quantum Rabi model (QRM), which is feasible within the framework of circuit QED. We begin by utilizing the two-photon interaction to implement the nonlinear sign (NS) gate, and subsequently, we construct the C-Z gate following the KLM scheme. We consider three different regimes: the strong coupling regime, the perturbative ultrastrong coupling regime, and the large detuning regime. Our results indicate that the C-Z gate operates fast with high fidelity, and is robust against decoherence. We also show the photonic state in the waveguide can be input into the circuit QED system through a variable coupler, and released after interaction with almost the same waveform except for a π\pi-phase shift. Our scheme offers a suitable approach for achieving fast and deterministic two-photon quantum gates via light-matter interactions.
By employing the Coulomb proximity potential model (CPPM) in conjunction with 22 distinct proximity potential models, we investigated the temperature dependence and the effects of proton number and neutron number on the diffusion parameters that determine the {\alpha}-decay half-lives of superheavy nuclei. The results indicate that the Prox.77-3 T-DEP proximity potential model yields the best performance, with the lowest root mean square deviation ({\sigma}=0.515), reflecting a high consistency with experimental data. In contrast, Bass77, AW95, Ngo80, and Guo2013 display larger deviations. The inclusion of temperature dependence significantly improves the accuracy of models such as Prox.77-3, Prox.77-6, and Prox.77-7. The -decay half-lives of 36 potential superheavy nuclei were further predicted using the five most accurate proximity potential models and Ni's empirical formula, with the results aligning well with experimental data. These predictions underscore the high reliability of the CPPM combined with proximity potential models in the theoretical calculation of {\alpha}-decay half-lives of superheavy nuclei, offering valuable theoretical insights for future experimental investigations of superheavy nuclei.
In this paper, we studied line operators in the Left-Right Symmetric Model. The gauge group of Left-Right Symmetric Electroweak Model is G=SU(3)×SU(2)L×SU(2)R×U(1)BL{G} = SU(3) \times SU(2)_{L} \times SU(2)_{R} \times U(1)_{B - L}. We derived the spectrum of line operators in all possible scenarios within left-right symmetric models. We then studied the θ\theta angles in left-right symmetric model. We also discuss the effect of symmetry breaking on the spectrum of line operators and θ\theta angles.
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