Chinese Physics C

This is the second part of the new evaluation of atomic masses, AME2020. Using least-squares adjustments to all evaluated and accepted experimental data, described in Part I, we derived tables with numerical values and graphs which supersede those given in AME2016. The first table presents the recommended atomic mass values and their uncertainties. It is followed by a table of the influences of data on primary nuclides, a table of various reaction and decay energies, and finally, a series of graphs of separation and decay energies. The last section of this paper provides all input data references that were used in the AME2020 and the NUBASE2020 evaluations.

The NUBASE2020 evaluation contains the recommended values of the main nuclear physics properties for all nuclei in their ground and excited, isomeric (T_1/2$\ge$100 ns) states. It encompasses all experimental data published in primary (journal articles) and secondary (mainly laboratory reports and conference proceedings) references, together with the corresponding bibliographical information. In cases where no experimental data were available for a particular nuclide, trends in the behavior of specific properties in neighboring nuclei were examined and estimated values are proposed. Evaluation procedures and policies that were used during the development of this evaluated nuclear data library are presented, together with a detailed table of recommended values and their uncertainties.

The mass spectra of charmonium are investigated using a Coulomb plus linear (Cornell) potential. Gaussian wave functions in position space as well as in momentum space are employed to calculate the expectation values of potential and kinetic energy respectively. Various experimental states (X(4660)(5³S₁), X(3872)(2³P₁), X(3900)(2¹P₁), X(3915)(2³P₀) and X(4274)(3³P₁) etc.) are assigned as charmonium states. We also study the Regge trajectories, pseudoscalar and vector decay constants, electric and magnetic dipole transition rates, and annihilation decay widths for charmonium states.

In this work, we make the first study of electroweak baryogenesis (EWBG) based on the LHC data in the CP-violating next-to-minimal supersymmetric model (NMSSM) where a strongly first order electroweak phase transition (EWPT) is obtained in the general complex Higgs potential. With representative benchmark points which pass the current LEP and LHC constraints, we demonstrate the structure of EWPT for those points and how a strongly first order EWPT is obtained in the complex NMSSM where the resulting gravitational wave production properties are found to be within the reaches of future space-based interferometers like BBO and Ultimate-DECIGO. We further calculate the generated baryon asymmetries where the CP violating sources are (1): higgsino-singlino dominated, (2): higgsino-gaugino dominated or (3): from both sources. It is shown that all three representing scenarios could evade the strong constraints set by various electric dipole moments (EDM) searches where cancellations among the EDM contributions occur at the tree level (higgsino-singlino dominated) or loop level (higgsino-gaugino dominated). The 125 GeV SM like Higgs can be either the second lightest neutral Higgs H₂ or the third lightest neutral Higgs H₃. Finally, we comment on the future direct and indirect probe of CPV in the Higgs sector from the collider and EDM experiments.

We propose to deploy limits that arise from different tests of the Pauli Exclusion Principle: i) to provide theories of quantum gravity with experimental guidance; ii) to distinguish, among the plethora of possible models, the ones that are already ruled out by current data; iii) to direct future attempts to be in accordance with experimental constraints. We first review experimental bounds on nuclear processes forbidden by the Pauli Exclusion Principle, which have been derived by several experimental collaborations making use of various detector materials. Distinct features of the experimental devices entail sensitivities on the constraints hitherto achieved that may differ from one another by several orders of magnitude. We show that with choices of these limits, well-known examples of flat noncommutative space-time instantiations of quantum gravity can be heavily constrained, and eventually ruled out. We devote particular attention to the analysis of the κ-Minkowski and θ-Minkowski noncommutative spacetimes. These are deeply connected to some scenarios in string theory, loop quantum gravity, and noncommutative geometry. We emphasize that the severe constraints on these quantum spacetimes, although they cannot rule out theories of top-down quantum gravity to which they are connected in various ways, provide a powerful limitation for those models. Focus on this will be necessary in the future.

We perform a global effective-field-theory analysis to assess the combined precision of Higgs couplings, triple gauge-boson couplings, and top-quark couplings, at future circular e⁺e⁻ colliders, with a focus on runs below the $t\bar{t}$ production threshold. Deviations in the top-quark sector entering as one-loop corrections are consistently taken into account in the Higgs and diboson processes. We find that future lepton colliders running at center-of-mass energies below the $t\bar{t}$ production threshold can still provide useful information on top-quark couplings, by measuring virtual top-quark effects. With rate and differential measurements, the indirect individual sensitivity achievable is better than at the high-luminosity LHC. However, strong correlations between the extracted top-quark and Higgs couplings are also present and lead to much weaker global constraints on top-quark couplings. This implies that a direct probe of top-quark couplings above the $t\bar{t}$ production threshold is also helpful for the determination of Higgs and triple-gauge-boson couplings. In addition, we find that below the ${e}^{+}{e}^{-}\to t\bar{t}h$ production threshold, the top-quark Yukawa coupling can be determined by its loop corrections to all Higgs production and decay channels. Degeneracy with the ggh coupling can be resolved, and even a global limit is competitive with the prospects of a linear collider above the threshold. This provides an additional means of determining the top-quark Yukawa coupling indirectly at lepton colliders.

The recent global analysis of three-flavor neutrino oscillation data indicates that the normal neutrino mass ordering is favored over the inverted one at the 3σ level, and the best-fit values of the largest neutrino mixing angle θ₂₃ and the Dirac CP-violating phase δ are located in the higher octant and third quadrant, respectively. We show that all these important issues can be naturally explained by the μ-τ reflection symmetry breaking of massive neutrinos from a superhigh energy scale down to the electroweak scale owing to the one-loop renormalization-group equations (RGEs) in the minimal supersymmetric standard model (MSSM). The complete parameter space is explored for the first time in both the Majorana and Dirac cases, by allowing the smallest neutrino mass m₁ and the MSSM parameter tanβ to vary within their reasonable regions.

The lowest-lying glueballs are investigated in lattice QCD using N_f = 2 clover Wilson fermions on anisotropic lattices. We simulate at two different and relatively heavy quark masses, corresponding to physical pion masses of m_π ∼ 938 MeV and 650 MeV. The quark mass dependence of the glueball masses has not been investigated in the present study. Only the gluonic operators built from Wilson loops are utilized in calculating the corresponding correlation functions. In the tensor channel, we obtain the ground state mass to be 2.363(39) GeV and 2.384(67) GeV at m_π ∼ 938 MeV and 650 MeV, respectively. In the pseudoscalar channel, when using the gluonic operator whose continuum limit has the form of ε_ijk TrB_iD_jB_k, we obtain the ground state mass to be 2.573(55) GeV and 2.585(65) GeV at the two pion masses. These results are compatible with the corresponding results in the quenched approximation. In contrast, if we use the topological charge density as field operators for the pseudoscalar, the masses of the lowest state are much lighter (around 1 GeV) and compatible with the expected masses of the flavor singlet ${\rm{q}}\bar{{\rm{q}}}$ meson. This indicates that the operator ε_ijk TrB_iD_jB_k and the topological charge density couple rather differently to the glueball states and ${\rm{q}}\bar{{\rm{q}}}$ mesons. The observation of the light flavor singlet pseudoscalar meson can be viewed as the manifestation of effects of dynamical quarks. In the scalar channel, the ground state masses extracted from the correlation functions of gluonic operators are determined to be around 1.4-1.5 GeV, which is close to the ground state masses from the correlation functions of the quark bilinear operators. In all cases, the mixing between glueballs and conventional mesons remains to be further clarified in the future.

In this study, Higgs and Z boson associated production with subsequent decay is attempted in the framework of alternative left-right model, which is motivated by superstring-inspired E₆ model at CEPC and future linear colliders. We systematically analyze each decay channel of Higgs with theoretical constraints and latest experimental methods. Due to the mixing of scalars in the Higgs sector, charged Higgs bosons can play an essential role in the phenomenological analysis of this process. Even though the predictions of this model for the signal strengths of this process are close to the standard model expectations, it can be distinct under high luminosity.

We develop a comprehensive dynamical framework, CIBJET, to calculate on an event-by-event basis the dependence of correlations between soft (p_T < 2 GeV) and hard (p_T > 10 GeV) azimuthal flow angle harmonics on the color composition of near-perfect QCD fluids produced in high energy nuclear collisions at RHIC and LHC. CIBJET combines consistently predictions of event-by-event VISHNU2+1 viscous hydrodynamic fluid fields with CUJET3.1 predictions of event-by-event jet quenching. We find that recent correlation data favor a temperature dependent color composition including bleached chromo-electric q(T)+g(T) components and an emergent chromo-magnetic degrees of freedom m(T) consistent with non-perturbative lattice QCD information in the confinement/deconfinement temperature range.

By combining the Skyrme-Hartree-Fock method with complex momentum representation (CMR), the resonant states of ${}^{17}_\Lambda$O, ${}^{41}_{\Lambda}$Ca, ${}^{49}_{\Lambda}$Ca, and ${}^{57}_\Lambda$Ni were investigated. The phase shifts for hyperon-nucleus elastic scattering were determined with continuum level density (CLD), and the scattering length as well as the resonance energy were obtained by utilizing the effective range expansion. Our method, abbreviated as CMR-CLD, exhibits good consistency with traditional approaches and provides ground work for investigating scattering and resonance problems in deformed and multi-hyperon hypernuclei.

In this study, we investigate the optical properties of a quantum-corrected black hole (BH) in loop quantum gravity surrounded by a plasma medium. First, we determine the photon and shadow radii resulting from quantum corrections and the plasma medium in the environment surrounding a quantum-corrected BH. Our findings indicate that the photon sphere and BH shadow radii decrease owing to the quantum correction parameter α, which acts as a repulsive gravitational charge. Further, we investigate the gravitational weak lensing by applying the general formalism used to model the deflection angle of the light traveling around the quantum-corrected BH within the plasma medium. We show, in conjunction with the fact that the combined effects of the quantum correction and non-uniform plasma frequency parameter can decrease the deflection angle, that the light traveling through the uniform plasma can be strongly deflected than the non-uniform plasma environment surrounding the quantum-corrected BH. Finally, we examine the magnification of the lensed image brightness under the effect of the quantum correction parameter α, including the uniform and non-uniform plasma effects.

This study explores the production of charged Higgs particles through photon-photon collisions within the context of the Two Higgs Doublet Model, including one-loop-level scattering amplitudes of electroweak and QED radiation. The cross-section has been scanned for the plane ($m_{\phi^{0}}, \sqrt{s}$) to investigate the process of $\gamma\gamma \rightarrow H^{+}H^{-}$. Three particular numerical scenarios, i.e., low-$m_{H}$, non-alignment, and short-cascade are employed. The decay channels for charged Higgs particles are examined using $h^{0}$ for low-$m_{H^{0}}$ and $H^{0}$for non-alignment and short-cascade scenarios incorporating the new experimental and theoretical constraints along with the analysis for cross-sections. We find that, at a low energy, the cross-section is consistently higher for all scenarios. However, as$\sqrt{s}$ increases, it reaches a peak value at 1$~$TeV for all benchmark scenarios. The branching ratio of the decay channels indicates that for non-alignment, the mode of decay $W^{\pm} h^{0}$ takes control, and for a short cascade, the prominent decay mode remains $t\overline {b}$, whereas in the low-$m_{H}$scenario, the dominant decay channel is of $W^{\pm} h^{0}$. In our research, we employ contemporary machine-learning methodologies to investigate the production of high-energy Higgs bosons within a 3.0 TeV $\gamma\gamma$ collider. We have used multivariate approaches such as Boosted Decision Trees (BDT), LikelihoodD, and Multilayer Perceptron (MLP) to show the observability of heavy-charged Higgs Bosons versus the most significant Standard Model backgrounds. The purity of the signal efficiency and background rejection are measured for each cut value.

The preformed cluster model (PCM) is applied to investigate the heavy particle radioactivity (HPR) and spontaneous fission (SF) processes for even-Z superheavy nuclear systems. Different proximity potentials are used to calculate the decay half-lives of $Z=112-120$ nuclei. The fragmentation potential and preformation distribution suggest that SF is the major contributor up to $Z=114$, and HPR starts competing for heavier nuclei. The heavy cluster emission is supported by Pb-magicity, whereas SF is reinforced owing to the deformations of fission fragments. The heavy cluster decay half-lives (log$_{10}$T_C) are calculated using the PCM and are compared with the estimates of the analytical super asymmetric fission (ASAF) model. The calculated log$_{10}$T_C values agree well with the ASAF measurements when using the Prox-00 and Mod Prox-00 versions of potentials. However, Prox-77, Prox-88, and Prox-BW-91 are not appropriate to address the log$_{10}$T_C for $Z \geq 116$ nuclei. To resolve this, we include Z-dependence in the radius parameters. Interestingly, the half-lives match the ASAF data after the inclusion of Z-dependence. The branching ratios are also calculated for superheavy nuclei and compared with the estimates of unified description (UD) formula, universal curve (UNIV), universal decay law (UDL), Horoi formula, and ASAF measurements. Furthermore, the SF half-lives ($T_{\rm SF}$) of $^{282}$Cn, $^{284}$Cn, $^{284}$Fl, and $^{286}$Fl superheavy nuclei are estimated through various proximity potentials. Among them, Prox-00 is appropriate for addressing the experimental data. Using this potential, the SF half-lives are estimated through the PCM for $Z=116-120$ isotopes at different neck-length parameters. Finally, the scaled total kinetic energy (TKE) values are compared with the available data.

The astrophysical S-factor of the ¹²C(p, γ₀)¹³N reaction at energies from 25 keV to 5 MeV within the framework of a modified potential cluster model with forbidden states is considered. The experimental phase shifts resonant ${\delta _{^2{S_{1/2}}}}$, ${\delta _{^2{P_{3/2}}}}$, and non-resonant ${\delta _{^2{D_{3/2}}}}$at the energies up to E_c.m. = 3 MeV are reproduced with high accuracy, which provides the appropriate agreement with the experimental data for the S-factor of 1950−2023 years. Two sets of asymptotic constant are used: Set I refers to C_w = 1.30(2), and Set II refers to C_w = 1.37(1). Set I leads to the astrophysical factor S(25) = 1.34 ± 0.02 keV·b, which is in agreement with data by Skowronski et al., 2023 – 1.34 ± 0.09 keV·b; Set II gives S(25) = 1.49 ± 0.02 keV·b, which is in agreement with data by Kettner et al., 2023 – 1.48 ± 0.09 keV·b. The reaction rates of ¹²C(p, γ₀)¹³N at temperatures T₉ from 0.001 to 10 are calculated. The detailed comparison with some models, the R-matrix approach, and NACRE II data for reaction rates is considered.

Electron-ion collision spectroscopy at heavy-ion storage rings aims at precision measurements of resonance features that occur in the cross sections of electron collision processes such as electron-impact ionization of ions or electron-ion recombination. As part of the international FAIR project the low-energy ion storage ring CRYRING@ESR has been coupled with the heavy-ion accelerators operated by the GSI Helmholtz Center for Heavy-Ion Research in Darmstadt, Germany. This opens up a new perspective for testing strong field quantum electrodynamics by electron-ion collision spectroscopy of heavy few-electron ions. The present contribution provides details of the electron-ion collision spectroscopy setup at CRYRING@ESR and of the associated data-analysis procedures along with first results for nonresonant and resonant recombination of berylliumlike lead ions. For nonresonant recombination a recombination rate enhancement factor of 3.5 is found at zero electron-ion collision energy. For resonant recombination there is excellent agreement with recent theoretical results when these are shifted by 340 meV in energy

Affleck-Dine baryogenesis generates high baryon density in the early Universe. The baryon chemical potential enhances the potential barrier and significantly reduces the decay rate of the false vacuum, which decreases from infinity at the critical end point to zero at the critical nucleation point. When the decay rate reaches zero, the false vacuum of high baryon density quark matter is unlikely to decay and can persist over cosmological time scales. Therefore the primordial quark nuggets can form and survive in the early Universe as the seeds of compact stars. This new mechanism for the formation of the primordial quark nuggets is different from Witten's stable droplet of quark matter. Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. Article funded by SCOAP3 and published under licence by Chinese Physical Society and the Institute of High Energy Physics of the Chinese Academy of Science and the Institute of Modern Physics of the Chinese Academy of Sciences and IOP Publishing Ltd.

Fusion excitation functions have been measured for the 16,18O + 50Cr systems at energies near and&#xD;below the Coulomb barrier, in order to study the positive Q-value two-neutron stripping channel&#xD;in 18O + 50Cr, wherein 16O + 50Cr was selected as a reference system. The coupling effect of&#xD;the inelastic excitation states in heavy-ion fusion reactions was conducted through a comparative&#xD;analysis of the two systems and based on the CCFULL calculations. The subtle under-estimation of&#xD;the calculated cross sections, by coupled-channels calculations including the 2+ vibrational state of&#xD;the target nucleus and the 2+ vibrational state of 18O projectile, leaves limited room for the widely&#xD;accepted positive Q-value 2n-transfer effect at the measured energy-region. Analogous systems of&#xD;neutron-rich 18O-induced fusion in the literatures show a systematic behavior that positive Q-value&#xD;two-neutron stripping channel has no remarkable influence on enhancing sub-barrier fusion cross&#xD;sections.&#xD;

To optimize the reaction conditions for synthesizing the superheavy element $Z = 119$, we examined the combinations of projectiles and target nuclei used by different countries: Japan with $^{51}\text{V} + {}^{248}\text{Cm}$, Russia potentially with $^{50}\text{Ti} + {}^{249}\text{Bk}$, and China currently with $^{54}\text{Cr} + {}^{243}\text{Am}$. Systematic studies were conducted by varying the incident energy from 210 MeV to 260 MeV. We analyzed the capture cross sections, fusion probabilities, survival probabilities, and evaporation residue cross sections (ERCS) for each reaction.&#xD;The objective is to identify the optimal incident energy that maximizes the efficiency of synthesizing $Z = 119$. Detailed plots were generated for capture cross sections, fusion probabilities, survival probabilities, and ERCS as functions of incident energy. The results aim to provide valuable insights for selecting the most effective incident energy for the synthesis of $Z = 119$.

The configuration interaction relativistic Hartree-Fock (CI-RHF) model is developed in this work. Compared to the conventional configuration interaction shell model (CISM), the CI-RHF model can be applied to study the structural properties of a wide range of nuclei without readjusting any parameters, as the effective Hamiltonian for different model space can be deduced consistently from a universal density-dependent Lagrangian based on the Hartree-Fock single-particle basis. The convergence of intermediate-state excitations has been examined in evaluating the effective interactions, and the core-polarization effects are illustrated, by using $^{18}$O as an example. Employing the CI-RHF model, both the bulk properties and low-lying spectra of even-even nuclei $^{18\sim 28}$Ne have been well reproduced with the model space restricted to the $sd$ shell. Studies of the isotopic evolution concerning charge radii and low-lying spectra highlight the shell closure at $N=14$ for neon isotopes. Furthermore, the cross-shell calculations extending from the $sd$ to $pf$ shell successfully reproduced the low-lying spectra of $^{30}$Ne and $^{32}$Ne. Notably, remarkably low excitation energies $E(2^{+}_{1})$ of $^{30}$Ne suggest the disappearance of the conventional magicity $N=20$.