2024 Vol. 48, No. 9
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2024, 48(9): 091001. doi: 10.1088/1674-1137/ad582a
Abstract:
The proton-proton (\begin{document}$ pp $\end{document} ![]()
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) fusion chain dominates the neutrino production in the Sun. The uncertainty of the predicted \begin{document}$ pp $\end{document} ![]()
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neutrino flux is at the sub-percent level, whereas that of the best measurement is \begin{document}$ {\cal{O}} $\end{document} ![]()
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(10%). In this study, for the first time, we measure solar \begin{document}$ pp $\end{document} ![]()
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neutrinos in the electron recoil energy range from 24 to 144 keV using the PandaX-4T commissioning data with 0.63 tonne \begin{document}$ \times $\end{document} ![]()
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year exposure. The \begin{document}$ pp $\end{document} ![]()
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neutrino flux is determined as \begin{document}$ (8.0 \pm 3.9 \,{\rm{(stat)}} \pm 10.0 \,{\rm{(syst)}} )\times 10^{10}\, $\end{document} ![]()
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\begin{document}$ \rm{s}^{-1} \rm{cm}^{-2} $\end{document} ![]()
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, which is consistent with the Standard Solar Model and existing measurements, corresponding to an upper flux limit of \begin{document}$ 23.3\times 10^{10}\, $\end{document} ![]()
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\begin{document}$ \rm{s}^{-1} \rm{cm}^{-2} $\end{document} ![]()
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at 90% C.L..
The proton-proton (
2024, 48(9): 093001. doi: 10.1088/1674-1137/ad595b
Abstract:
The number of ψ(3686) events collected by the BESIII detector during the 2021 run period is determined to be (2259.3±11.1)×106 by counting inclusive ψ(3686) hadronic events. The uncertainty is systematic and the statistical uncertainty is negligible. Meanwhile, the numbers of ψ(3686) events collected during the 2009 and 2012 run periods are updated to be (107.7±0.6)×106 and (345.4±2.6)×106, respectively. Both numbers are consistent with the previous measurements within one standard deviation. The total number of ψ(3686) events in the three data samples is (2712.4±14.3)×106.
The number of ψ(3686) events collected by the BESIII detector during the 2021 run period is determined to be (2259.3±11.1)×106 by counting inclusive ψ(3686) hadronic events. The uncertainty is systematic and the statistical uncertainty is negligible. Meanwhile, the numbers of ψ(3686) events collected during the 2009 and 2012 run periods are updated to be (107.7±0.6)×106 and (345.4±2.6)×106, respectively. Both numbers are consistent with the previous measurements within one standard deviation. The total number of ψ(3686) events in the three data samples is (2712.4±14.3)×106.
2024, 48(9): 093101. doi: 10.1088/1674-1137/ad5427
Abstract:
We study the SM-like Higgs boson decays\begin{document}$ h\rightarrow MZ $\end{document} ![]()
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in the triplet extended NMSSM (TNMSSM), where M is a vector meson \begin{document}$(\rho,\omega,\phi,J/\psi,\Upsilon)$\end{document} ![]()
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. Compared to the minimal supersymmetric standard model (MSSM), the TNMSSM includes two new \begin{document}$ S U$\end{document} ![]()
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(2) triplets with hypercharge ±1 and an SM gauge singlet, which are coupled to each other. The indirect contributions to the \begin{document}$ h\rightarrow MZ $\end{document} ![]()
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decays are produced from the effective \begin{document}$ h\gamma Z $\end{document} ![]()
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vertex, and they are more important than the direct contributions. The results of this work could encourage a detection on \begin{document}$ h\rightarrow Z\gamma $\end{document} ![]()
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at the future high energy colliders for exploring new physics beyond the SM.
We study the SM-like Higgs boson decays
2024, 48(9): 093102. doi: 10.1088/1674-1137/ad4d61
Abstract:
Heavy neutral leptons N are the most appealing candidates to generate tiny neutrino masses. We studied the signature of heavy neutral leptons in gauged\begin{document}$ U(1)_{L_\mu-L_\tau} $\end{document} ![]()
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at a muon collider. Charged under the \begin{document}$ U(1)_{L_\mu-L_\tau} $\end{document} ![]()
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symmetry, the heavy neutral leptons can be pair produced via the new gauge boson \begin{document}$ Z' $\end{document} ![]()
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at the muon collider as \begin{document}$ \mu^+\mu^-\to Z^{\prime *}\to NN $\end{document} ![]()
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and \begin{document}$ \mu^+\mu^-\to Z^{\prime (*)} \gamma\to NN\gamma $\end{document} ![]()
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. We then performed a detailed analysis on the lepton number violation signature \begin{document}$ \mu^+\mu^-\to NN\to \mu^\pm\mu^\pm W^\mp W^\mp $\end{document} ![]()
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and \begin{document}$ \mu^+\mu^-\to NN \gamma\to \mu^\pm\mu^\pm W^\mp W^\mp \gamma $\end{document} ![]()
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at the 3 TeV muon collider, where the hadronic decays of W boson are treated as fat-jets J. These lepton number violation signatures have quite clean backgrounds at the muon collider. Our simulation shows that a wide range of viable parameter space is within the reach of the 3 TeV muon collider. For instance, with new gauge coupling \begin{document}$ g'=0.6 $\end{document} ![]()
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and an integrated luminosity of 1000 fb\begin{document}$ ^{-1} $\end{document} ![]()
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, the \begin{document}$ \mu^\pm\mu^\pm JJ $\end{document} ![]()
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signal could probe \begin{document}$ m_{Z'}\lesssim 13 $\end{document} ![]()
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TeV. Meanwhile, if the gauge boson mass satisfies \begin{document}$ 2 m_N<m_{Z'}<\sqrt{s} $\end{document} ![]()
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, the \begin{document}$ \mu^\pm\mu^\pm JJ\gamma $\end{document} ![]()
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signature would be more promising than the \begin{document}$ \mu^\pm\mu^\pm JJ $\end{document} ![]()
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signature.
Heavy neutral leptons N are the most appealing candidates to generate tiny neutrino masses. We studied the signature of heavy neutral leptons in gauged
2024, 48(9): 093103. doi: 10.1088/1674-1137/ad53b7
Abstract:
In this study, we evaluated the mass spectra of the prospective\begin{document}$ 0^{--} $\end{document} ![]()
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hidden-charm and hidden-bottom tetraquark states in molecular configuration via QCD sum rules. In our calculation, the nonperturbative condensate contributions are considered up to dimension eight in operator product expansion. It is found that there could exist 4 possible \begin{document}$ 0^{--} $\end{document} ![]()
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hidden-charm tetraquark states with masses \begin{document}$ (4.68\pm0.07) $\end{document} ![]()
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, \begin{document}$ (4.22\pm0.09) $\end{document} ![]()
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, \begin{document}$ (4.53\pm0.09) $\end{document} ![]()
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, and \begin{document}$ (4.26\pm0.13) $\end{document} ![]()
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GeV. Their corresponding hidden-bottom partners are found lying at \begin{document}$ (11.04\pm0.10) $\end{document} ![]()
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, \begin{document}$ (10.71\pm0.12) $\end{document} ![]()
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, \begin{document}$ (11.09\pm0.10) $\end{document} ![]()
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, and \begin{document}$ (11.82\pm0.14) $\end{document} ![]()
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GeV, respectively. The possible tetraquark decay modes were analyzed, which are expected to be measured in BESIII, BELLEII, and LHCb experiments.
In this study, we evaluated the mass spectra of the prospective
2024, 48(9): 093104. doi: 10.1088/1674-1137/ad57a7
Abstract:
In this study, we explore the potentials of dipole operators and four-fermion operators at low-energy lepton colliders such as Belle II and the Super Tau Charm Facility (STCF). We utilize high-dimension operators to characterize such anomalous interactions, focusing on those that do not interfere with the Standard Model (SM) contributions. With polarized beams, the four-fermion operators and dipole moment operators can be tested with high precision.
In this study, we explore the potentials of dipole operators and four-fermion operators at low-energy lepton colliders such as Belle II and the Super Tau Charm Facility (STCF). We utilize high-dimension operators to characterize such anomalous interactions, focusing on those that do not interfere with the Standard Model (SM) contributions. With polarized beams, the four-fermion operators and dipole moment operators can be tested with high precision.
2024, 48(9): 093105. doi: 10.1088/1674-1137/ad53bb
Abstract:
In the present study, we investigated the decays of the top quark:\begin{document}$ t\rightarrow c\gamma $\end{document} ![]()
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, \begin{document}$ t\rightarrow cg $\end{document} ![]()
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, \begin{document}$ t\rightarrow cZ $\end{document} ![]()
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, and \begin{document}$ t\rightarrow ch $\end{document} ![]()
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. They are extremely rare processes in the standard model (SM). As the \begin{document}$ U(1) $\end{document} ![]()
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extension of the minimal supersymmetric standard model (MSSM), the \begin{document}$ U(1)_X $\end{document} ![]()
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SSM features new superfields such as the right-handed neutrinos and three Higgs singlets. We analyzed the effects of different sensitive parameters on the results and made reasonable theoretical predictions, thereby providing a useful reference for future experimental development. Considering the constraint set by the updated experimental data, the numerical results show that the branching ratios of the four processes, i.e., \begin{document}$ t\rightarrow c\gamma,\; cg,\; cZ,\; ch $\end{document} ![]()
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, can reach the same order of magnitude as their experimental upper limits. Among them, \begin{document}$ \tan\beta $\end{document} ![]()
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has the most evident effect on these processes and is the main parameter; \begin{document}$ g_X $\end{document} ![]()
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, \begin{document}$ g_{YX} $\end{document} ![]()
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, \begin{document}$ \mu $\end{document} ![]()
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, \begin{document}$ M_2 $\end{document} ![]()
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, \begin{document}$ \lambda_H $\end{document} ![]()
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, \begin{document}$ M_{U23}^2 $\end{document} ![]()
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, and \begin{document}$ M_{Q23}^2 $\end{document} ![]()
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are also important parameters for the processes, and have effects on the numerical results.
In the present study, we investigated the decays of the top quark:
2024, 48(9): 093106. doi: 10.1088/1674-1137/ad5426
Abstract:
Motivated by the recent experimental results of branching fractions for\begin{document}$ {D}_{\left(s\right)}^{+}\to {\eta }^{\left({'}\right)}\overline{l}{\nu }_{l} $\end{document} ![]()
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decays, which deviate from their SM predictions, we hve investigated these decays in \begin{document}${W}'$\end{document} ![]()
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model and scalar leptoquark model to determine potential signatures of new physics (NP) in semileptonic charm decays induced by \begin{document}$ c\to (s,d)\overline{l}{\nu }_{l} $\end{document} ![]()
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transitions. Using recent experimental results of branching fractions for semileptonic \begin{document}$ D $\end{document} ![]()
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meson decays, new coupling parameters are predicted for the aforementioned NP models. Branching fraction, forward-backward asymmetry, and lepton polarization asymmetry are examined by considering the predicted NP coupling parameters. The results of branching fractions in scalar leptoquark model are found very close to the experimental results and exist around the range of \begin{document}$ 1\sigma $\end{document} ![]()
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deviation. We presented a comparative study of the NP models to check their sensitivity on these decays. We anticipate that further research on these decays will significantly support our findings.
Motivated by the recent experimental results of branching fractions for
2024, 48(9): 093107. doi: 10.1088/1674-1137/ad53bd
Abstract:
The unquenched quark model for the light quarkonium and charmonium states is explored in this study. The quark-pair creation operator in the\begin{document}$^3P_0$\end{document} ![]()
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model, which combines the two-quark and four-quark components, is modified by considering the effects of the created quark pair's energy. Furthermore, the separation between the created quark pair and valence quark pair is modified. All the wave functions, including those for the mesons and the relative motion between two mesons, are obtained by solving the corresponding Schrödinger equation using the Gaussian expansion method. The aim of this study is to find a new set of parameters that can accurately describe the mass spectrum of low-lying light quarkonium and charmonium states. Moreover, certain exotic states, such as \begin{document}$X(3872)$\end{document} ![]()
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, can be described well in the unquenched quark model.
The unquenched quark model for the light quarkonium and charmonium states is explored in this study. The quark-pair creation operator in the
2024, 48(9): 093108. doi: 10.1088/1674-1137/ad5663
Abstract:
In this study, we explore the detectability of heavy Higgs bosons in the\begin{document}$ pp \to b\bar{b}H/A \to b\bar{b}t\bar{t} $\end{document} ![]()
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channel at a 100 TeV hadron collider within the semi-constrained next-to-minimal supersymmetric standard model. We calculate their production cross sections and decay branching ratios and compare them with simulation results from literature. We focus on the heavy doublet-dominated CP-even Higgs H and CP-odd Higgs A, with mass limits set below 10 TeV to ensure detectability. At a collider with an integrated luminosity of 3 ab\begin{document}$ ^{-1} $\end{document} ![]()
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, the potential for detecting heavy Higgs bosons varies significantly with their mass and \begin{document}$ \tan\beta $\end{document} ![]()
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. Heavy Higgs bosons with masses below 2 TeV are within the testable range, while those heavier than 7 TeV are below the exclusion and discovery thresholds, rendering them undetectable. For masses between 2 and 7 TeV, heavy Higgs bosons with \begin{document}$ \tan\beta $\end{document} ![]()
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smaller than 20 can be detected, whereas those with \begin{document}$ \tan\beta $\end{document} ![]()
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larger than 20 are beyond the current discovery or exclusion capabilities.
In this study, we explore the detectability of heavy Higgs bosons in the
2024, 48(9): 093109. doi: 10.1088/1674-1137/ad5ae9
Abstract:
In this study, a comprehensive analysis of jets and underlying events as a function of charged particle multiplicity in proton-proton (pp) collisions at a center-of-mass energy of\begin{document}$ \sqrt{s} = 7 $\end{document} ![]()
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TeV is conducted. Various Monte Carlo (MC) event generators, including Pythia8.308, EPOS1.99, EPOSLHC, EPOS4 \begin{document}$_{\rm Hydro}$\end{document} ![]()
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, and EPOS4\begin{document}$_{\rm noHydro}$\end{document} ![]()
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, are employed to predict particle production. The predictions from these models are compared with experimental data from the CMS collaboration. The charged particles are categorized into those associated with underlying events and those linked to jets, and the analysis is restricted to charged particles with \begin{document}$ |\eta| < 2.4 $\end{document} ![]()
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and \begin{document}$ p_{T} > 0.25 $\end{document} ![]()
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GeV/c. By comparing the MC predictions with CMS data, we find that EPOS\begin{document}$4_{\rm Hydro}$\end{document} ![]()
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, EPOSLHC, and Pythia8 consistently reproduce the experimental results for all charged particles, underlying events, intrajets, and leading charged particles. For charged jet rates with \begin{document}$p_{T}^{\rm ch.jet} > 5$\end{document} ![]()
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GeV/c, EPOS4\begin{document}$_{\rm Hydro}$\end{document} ![]()
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and Pythia8 perform exceptionally well. In the case of charged jet rates with \begin{document}$p_{T}^{\rm ch.jet} > 30$\end{document} ![]()
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GeV/c, EPOSLHC reproduces satisfactorily good results, whereas EPOS4 \begin{document}$_{\rm Hydro}$\end{document} ![]()
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exhibits good agreement with the data at higher charged particle multiplicities compared to the other models. This can be attributed to the conversion of energy into flow when "Hydro=on," leading to an increase in multiplicity. The EPOSLHC model describes the data better owing to the new collective flow effects, correlated flow treatment, and parameterization compared to EPOS1.99. However, the examination of the jet \begin{document}$ p_{T} $\end{document} ![]()
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spectrum and normalized charged \begin{document}$ p_{T} $\end{document} ![]()
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density reveals that EPOS4\begin{document}$_{\rm Hydro}$\end{document} ![]()
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, EPOS4\begin{document}$_{\rm noHydro}$\end{document} ![]()
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, and EPOSLHC exhibit good agreement with the experimental results, whereas Pythia8 and EPOS1.99 do not perform as well owing to the lack of correlated flow treatment.
In this study, a comprehensive analysis of jets and underlying events as a function of charged particle multiplicity in proton-proton (pp) collisions at a center-of-mass energy of
2024, 48(9): 093110. doi: 10.1088/1674-1137/ad5bd5
Abstract:
This paper presents a comprehensive analysis of the MD-BFKL equation, considering both shadowing and anti-shadowing effects in gluon recombination processes. By deriving analytical expressions for unintegrated gluon distributions through the solution of the MD-BFKL equation, with and without the incorporation of the anti-shadowing effect, we offer new insights into the influence of these effects on the behavior of unintegrated gluon distributions. Our results, when compared to those from the CT18NLO gluon distribution function, demonstrate that the anti-shadowing effect has a notably stronger impact on the characteristics of unintegrated gluon distributions, particularly in regions of high rapidity and momentum. This work significantly contributes to the understanding of gluon recombination mechanisms and their implications in high energy physics.
This paper presents a comprehensive analysis of the MD-BFKL equation, considering both shadowing and anti-shadowing effects in gluon recombination processes. By deriving analytical expressions for unintegrated gluon distributions through the solution of the MD-BFKL equation, with and without the incorporation of the anti-shadowing effect, we offer new insights into the influence of these effects on the behavior of unintegrated gluon distributions. Our results, when compared to those from the CT18NLO gluon distribution function, demonstrate that the anti-shadowing effect has a notably stronger impact on the characteristics of unintegrated gluon distributions, particularly in regions of high rapidity and momentum. This work significantly contributes to the understanding of gluon recombination mechanisms and their implications in high energy physics.
2024, 48(9): 094001. doi: 10.1088/1674-1137/ad50b9
Abstract:
The complete and incomplete fusion cross section as well as one-neutron stripping process of 6Li + 94Zr system were measured at the energies around the Coulomb barrier by online γ-ray method. In addition to a 30% suppression factor when compared with the measured total fusion process, the complete fusion cross section in 6Li + 94Zr system was observed to be significantly lower than those in the nearby 6Li + 90, 96Zr system. The new experimental result implies that the coupling with breakup channel in the 6Li-induced fusion processes can be affected by the inner structure of the target, which is still not clear in any available model calculation. For the one-neutron stripping process, the direct production cross sections for each level in 95Zr were extracted and compared with the coupled reaction channel calculation, offering a unique opportunity to examine the single-particle nature of the produced excited states. Given the fact that an overall overestimation of the production cross section for 954-keV and 1618-keV levels was observed in the comparison, further investigation is highly demanded in order to understand the full reaction mechanism for the one-neutron stripping process induced by 6Li.
The complete and incomplete fusion cross section as well as one-neutron stripping process of 6Li + 94Zr system were measured at the energies around the Coulomb barrier by online γ-ray method. In addition to a 30% suppression factor when compared with the measured total fusion process, the complete fusion cross section in 6Li + 94Zr system was observed to be significantly lower than those in the nearby 6Li + 90, 96Zr system. The new experimental result implies that the coupling with breakup channel in the 6Li-induced fusion processes can be affected by the inner structure of the target, which is still not clear in any available model calculation. For the one-neutron stripping process, the direct production cross sections for each level in 95Zr were extracted and compared with the coupled reaction channel calculation, offering a unique opportunity to examine the single-particle nature of the produced excited states. Given the fact that an overall overestimation of the production cross section for 954-keV and 1618-keV levels was observed in the comparison, further investigation is highly demanded in order to understand the full reaction mechanism for the one-neutron stripping process induced by 6Li.
2024, 48(9): 094101. doi: 10.1088/1674-1137/ad5428
Abstract:
The neutron capture rates and temperature dependent stellar beta decay rates of Mo isotopes are investigated within the framework of the statistical code TALYS v1.96 and the proton neutron quasi particle random phase approximation (pn-QRPA) model. The Maxwellian average cross-section (MACS) and neutron capture rates for the\begin{document}$ ^{95-98} $\end{document} ![]()
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Mo(n,γ)\begin{document}$ ^{96-99} $\end{document} ![]()
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Mo radiative capture process are analyzed within the framework of the statistical code TALYS v1.96 based on the phenomenological nuclear level density model and gamma strength functions. The present model-based computations for the MACS are comparable to the existing measured data. The sensitivity of stellar weak interaction rates to various densities and temperatures is investigated within the framework of the pn-QRPA model. Particular attention is paid to the impact of thermally filled excited states in the decaying nuclei (\begin{document}$ ^{95-98} $\end{document} ![]()
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Mo) on electron emission and positron capture rates. Furthermore, we compare the neutron capture rates and stellar beta decay rates. It is found that neutron capture rates are higher than stellar beta decay rates at both lower and higher temperatures.
The neutron capture rates and temperature dependent stellar beta decay rates of Mo isotopes are investigated within the framework of the statistical code TALYS v1.96 and the proton neutron quasi particle random phase approximation (pn-QRPA) model. The Maxwellian average cross-section (MACS) and neutron capture rates for the
2024, 48(9): 094102. doi: 10.1088/1674-1137/ad4f70
Abstract:
Recently, studies have argued that a spherical-like spectrum emerges in the SU3-IBM, thus creating new approaches to understanding γ-softness in realistic nuclei. In a previous study, γ-softness with degeneracy of the ground and quasi-γ bands was observed. In this paper, another special point connected to the middle degenerate point is discussed. It is found to be related to the properties of 196Pt. This emergent γ-softness is also shown to be important for understanding the prolate-oblate asymmetric shape phase transition. The low-lying spectra,\begin{document}$ B(E2) $\end{document} ![]()
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values, and quadrupole moments in 196Pt are discussed, and we show that the new model can account for several observed features. This is the first part of the discussion on the γ-soft-like spectrum of 196Pt.
Recently, studies have argued that a spherical-like spectrum emerges in the SU3-IBM, thus creating new approaches to understanding γ-softness in realistic nuclei. In a previous study, γ-softness with degeneracy of the ground and quasi-γ bands was observed. In this paper, another special point connected to the middle degenerate point is discussed. It is found to be related to the properties of 196Pt. This emergent γ-softness is also shown to be important for understanding the prolate-oblate asymmetric shape phase transition. The low-lying spectra,
2024, 48(9): 094103. doi: 10.1088/1674-1137/ad53b8
Abstract:
Based on the Weizsäcker-Skyrme (WS4) mass model, the fission barriers of nuclei are systematically studied. Considering the shell corrections, macroscopic deformation energy, and a phenomenological residual correction, the fission barrier heights for nuclei with\begin{document}$Z\geqslant 82$\end{document} ![]()
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can be well described, with an rms deviation of 0.481 MeV with respect to 71 empirical barrier heights. In addition to the shell correction at the ground state, the shell correction at the saddle point and its relative value are also important for both deformed and spherical nuclei. The fission barriers for nuclei far from the \begin{document}$\beta$\end{document} ![]()
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-stability line and super-heavy nuclei are also predicted with the proposed approach.
Based on the Weizsäcker-Skyrme (WS4) mass model, the fission barriers of nuclei are systematically studied. Considering the shell corrections, macroscopic deformation energy, and a phenomenological residual correction, the fission barrier heights for nuclei with
2024, 48(9): 094104. doi: 10.1088/1674-1137/ad5662
Abstract:
In this study, we measured the 58Ni(n, p)58Co reaction cross section with neutron energies of 1.06, 1.86, and 2.85 MeV. The cross section was measured using neutron activation techniques and γ-ray spectroscopy, and it was compared with cross section data available in the EXFOR. Furthermore, we calculated the covariance matrix of the measured cross section for the aforementioned nuclear reaction. The uncertainties of the theoretical calculation for 58Ni(n, p)58Co reaction cross section were calculated via Monte Carlo method. In this study, we used uncertainties in the optical model and level density parameters to calculate uncertainties in the theoretical cross sections. The theoretical calculations were performed by using TALYS-1.96. In this study, we aim to analyze the effect of uncertainties of the nuclear model input as well as different experimental variables used to obtain the values of reaction cross section.
In this study, we measured the 58Ni(n, p)58Co reaction cross section with neutron energies of 1.06, 1.86, and 2.85 MeV. The cross section was measured using neutron activation techniques and γ-ray spectroscopy, and it was compared with cross section data available in the EXFOR. Furthermore, we calculated the covariance matrix of the measured cross section for the aforementioned nuclear reaction. The uncertainties of the theoretical calculation for 58Ni(n, p)58Co reaction cross section were calculated via Monte Carlo method. In this study, we used uncertainties in the optical model and level density parameters to calculate uncertainties in the theoretical cross sections. The theoretical calculations were performed by using TALYS-1.96. In this study, we aim to analyze the effect of uncertainties of the nuclear model input as well as different experimental variables used to obtain the values of reaction cross section.
2024, 48(9): 095001. doi: 10.1088/1674-1137/ad50ab
Abstract:
The exponential growth of astronomical datasets provides an unprecedented opportunity for humans to gain insight into the Universe. However, effectively analyzing this vast amount of data poses a significant challenge. In response, astronomers are turning to deep learning techniques, but these methods are limited by their specific training sets, leading to considerable duplicate workloads. To overcome this issue, we built a framework for the general analysis of galaxy images based on a large vision model (LVM) plus downstream tasks (DST), including galaxy morphological classification, image restoration, object detection, parameter extraction, and more. Considering the low signal-to-noise ratios of galaxy images and the imbalanced distribution of galaxy categories, we designed our LVM to incorporate a Human-in-the-loop (HITL) module, which leverages human knowledge to enhance the reliability and interpretability of processing galaxy images interactively. The proposed framework exhibits notable few-shot learning capabilities and versatile adaptability for all the abovementioned tasks on galaxy images in the DESI Legacy Imaging Surveys. In particular, for the object detection task, which was trained using 1000 data points, our DST in the LVM achieved an accuracy of 96.7%, while ResNet50 plus Mask R-CNN reached an accuracy of 93.1%. For morphological classification, to obtain an area under the curve (AUC) of ~0.9, LVM plus DST and HITL only requested 1/50 of the training sets that ResNet18 requested. In addition, multimodal data can be integrated, which creates possibilities for conducting joint analyses with datasets spanning diverse domains in the era of multi-messenger astronomy.
The exponential growth of astronomical datasets provides an unprecedented opportunity for humans to gain insight into the Universe. However, effectively analyzing this vast amount of data poses a significant challenge. In response, astronomers are turning to deep learning techniques, but these methods are limited by their specific training sets, leading to considerable duplicate workloads. To overcome this issue, we built a framework for the general analysis of galaxy images based on a large vision model (LVM) plus downstream tasks (DST), including galaxy morphological classification, image restoration, object detection, parameter extraction, and more. Considering the low signal-to-noise ratios of galaxy images and the imbalanced distribution of galaxy categories, we designed our LVM to incorporate a Human-in-the-loop (HITL) module, which leverages human knowledge to enhance the reliability and interpretability of processing galaxy images interactively. The proposed framework exhibits notable few-shot learning capabilities and versatile adaptability for all the abovementioned tasks on galaxy images in the DESI Legacy Imaging Surveys. In particular, for the object detection task, which was trained using 1000 data points, our DST in the LVM achieved an accuracy of 96.7%, while ResNet50 plus Mask R-CNN reached an accuracy of 93.1%. For morphological classification, to obtain an area under the curve (AUC) of ~0.9, LVM plus DST and HITL only requested 1/50 of the training sets that ResNet18 requested. In addition, multimodal data can be integrated, which creates possibilities for conducting joint analyses with datasets spanning diverse domains in the era of multi-messenger astronomy.
2024, 48(9): 095101. doi: 10.1088/1674-1137/ad53ba
Abstract:
Phase transition is important for understanding the nature and evolution of the black hole thermodynamic system. In this study, we predicted the phase transition of the third-order Lovelock black hole using the winding numbers in complex analysis, and qualitatively validated this prediction by the generalized free energy. For the 7<d<12-dimensional black holes in hyperbolic topology and the 7-dimensional black hole in spherical topology, the winding number obtained is three, which indicates that the system undergoes first-order and second-order phase transitions. For the 7<d<12-dimensional black holes in spherical topology, the winding number is four, and two scenarios of phase transitions exist, one involving a purely second-order phase transition and the other involving simultaneous first-order and second-order phase transitions. This result further deepens the research on black hole phase transitions using the complex analysis.
Phase transition is important for understanding the nature and evolution of the black hole thermodynamic system. In this study, we predicted the phase transition of the third-order Lovelock black hole using the winding numbers in complex analysis, and qualitatively validated this prediction by the generalized free energy. For the 7<d<12-dimensional black holes in hyperbolic topology and the 7-dimensional black hole in spherical topology, the winding number obtained is three, which indicates that the system undergoes first-order and second-order phase transitions. For the 7<d<12-dimensional black holes in spherical topology, the winding number is four, and two scenarios of phase transitions exist, one involving a purely second-order phase transition and the other involving simultaneous first-order and second-order phase transitions. This result further deepens the research on black hole phase transitions using the complex analysis.
2024, 48(9): 095102. doi: 10.1088/1674-1137/ad50aa
Abstract:
In this article, we present a dynamical system analysis of a Dirac-Born-Infeld scalar field in a modified\begin{document}$ f(Q) $\end{document} ![]()
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gravity context. We considered a polynomial form of modified gravity, used two different types of scalar potential, polynomial and exponential, and found a closed autonomous dynamical system of equations. We analyzed the fixed points of such a system and evaluated the conditions under which deceleration to late-time acceleration occurs in this model. We note the similarity of the two models and show that our result is consistent with a previous study on Einstein's gravity. We also investigated the phenomenological implications of our models by plotting EoS (ω), energy density (Ω), and deceleration parameter (q) w.r.t. to e-fold time and comparing to the present value. We conclude the paper by observing how the dynamical system analysis differs in the modified \begin{document}$ f(Q) $\end{document} ![]()
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gravity, and present the future scope of our research.
In this article, we present a dynamical system analysis of a Dirac-Born-Infeld scalar field in a modified
2024, 48(9): 095103. doi: 10.1088/1674-1137/ad50ba
Abstract:
In this study, we investigate the detectability of the secondary spin in an extreme mass ratio inspiral (EMRI) system within a modified gravity model coupled with a scalar field. The central black hole, which reduces to a Kerr one, is circularly spiralled by a scalar-charged spinning secondary body on the equatorial plane. The analysis reveals that the presence of the scalar field amplifies the secondary spin effect, allowing for a lower limit of the detectability and an improved resolution of the secondary spin when the scalar charge is sufficiently large. Our findings suggest that secondary spin detection is more feasible when the primary mass is not large, and TianQin is the optimal choice for detection.
In this study, we investigate the detectability of the secondary spin in an extreme mass ratio inspiral (EMRI) system within a modified gravity model coupled with a scalar field. The central black hole, which reduces to a Kerr one, is circularly spiralled by a scalar-charged spinning secondary body on the equatorial plane. The analysis reveals that the presence of the scalar field amplifies the secondary spin effect, allowing for a lower limit of the detectability and an improved resolution of the secondary spin when the scalar charge is sufficiently large. Our findings suggest that secondary spin detection is more feasible when the primary mass is not large, and TianQin is the optimal choice for detection.
2024, 48(9): 095104. doi: 10.1088/1674-1137/ad5ae4
Abstract:
Cosmological observations can be used to weigh neutrinos, but this method is model-dependent, with results relying on the cosmological model considered. If we consider interactions between dark energy and dark matter, the neutrino mass constraints differ from those derived under the standard model. On the contrary, gravitational wave (GW) standard siren observations can measure absolute cosmological distances, helping to break parameter degeneracies inherent in traditional cosmological observations, thereby improving constraints on neutrino mass. This paper examines the constraints on neutrino mass within interacting dark energy (IDE) models and explores how future GW standard siren observations could enhance these results. For multi-messenger GW observations, we consider the joint observations of binary neutron star mergers by third-generation ground-based GW detectors and short γ-ray burst observations by missions similar to the THESEUS satellite project. Using current cosmological observations (CMB+BAO+SN), we obtain an upper limit on the neutrino mass in the IDE models of 0.15 (or 0.16) eV. With the inclusion of GW data, the upper limit on the neutrino mass improves to 0.14 eV. This indicates that in the context of IDE models, the improvement in neutrino mass constraints from GW observations is relatively limited. However, GW observations significantly enhance the constraints on other cosmological parameters, such as matter density parameter, the Hubble constant, and coupling strength between dark energy and dark matter.
Cosmological observations can be used to weigh neutrinos, but this method is model-dependent, with results relying on the cosmological model considered. If we consider interactions between dark energy and dark matter, the neutrino mass constraints differ from those derived under the standard model. On the contrary, gravitational wave (GW) standard siren observations can measure absolute cosmological distances, helping to break parameter degeneracies inherent in traditional cosmological observations, thereby improving constraints on neutrino mass. This paper examines the constraints on neutrino mass within interacting dark energy (IDE) models and explores how future GW standard siren observations could enhance these results. For multi-messenger GW observations, we consider the joint observations of binary neutron star mergers by third-generation ground-based GW detectors and short γ-ray burst observations by missions similar to the THESEUS satellite project. Using current cosmological observations (CMB+BAO+SN), we obtain an upper limit on the neutrino mass in the IDE models of 0.15 (or 0.16) eV. With the inclusion of GW data, the upper limit on the neutrino mass improves to 0.14 eV. This indicates that in the context of IDE models, the improvement in neutrino mass constraints from GW observations is relatively limited. However, GW observations significantly enhance the constraints on other cosmological parameters, such as matter density parameter, the Hubble constant, and coupling strength between dark energy and dark matter.
2024, 48(9): 095105. doi: 10.1088/1674-1137/ad5a70
Abstract:
In this study, we investigated the optical properties of charged black holes within the Einstein-Maxwell-scalar (EMS) theory. We evaluated the shadow cast by these black holes and obtained analytical solutions for both the radius of the photon sphere and that of the shadow. We observed that black hole parameters γ and β both influence the shadow of black holes. We also found that the photon sphere and shadow radius increase as a consequence of the presence of the parameter γ. Interestingly, the shadow radius decreases first and then remains unchanged owing to the impact of the parameter β. Finally, we analyzed the weak gravitational lensing and total magnification of lensed images around black holes. We found that the charge of the black holes and the parameter β both have a significant impact, reducing the deflection angle. Similarly, the same behavior for the total magnification was observed, also as a result of the effect of the charge of the black holes and the parameter β.
In this study, we investigated the optical properties of charged black holes within the Einstein-Maxwell-scalar (EMS) theory. We evaluated the shadow cast by these black holes and obtained analytical solutions for both the radius of the photon sphere and that of the shadow. We observed that black hole parameters γ and β both influence the shadow of black holes. We also found that the photon sphere and shadow radius increase as a consequence of the presence of the parameter γ. Interestingly, the shadow radius decreases first and then remains unchanged owing to the impact of the parameter β. Finally, we analyzed the weak gravitational lensing and total magnification of lensed images around black holes. We found that the charge of the black holes and the parameter β both have a significant impact, reducing the deflection angle. Similarly, the same behavior for the total magnification was observed, also as a result of the effect of the charge of the black holes and the parameter β.
2024, 48(9): 095106. doi: 10.1088/1674-1137/ad53b9
Abstract:
In this study, we investigate the bulk-boundary and restricted phase space (RPS) thermodynamics of Rissner-Nordström (R-N) AdS and 6-dimensional charged Gauss-Bonnet AdS black holes. Additionally, we examine the topological characteristics of the considered black holes and compare them with the results of extended thermodynamics. We determine that the topological behavior of the bulk-boundary thermodynamics is the same as that of the extended thermodynamics, whereas the RPS thermodynamics exhibits a distinct behavior. Furthermore, we demonstrate that within the RPS formalism, there is only one critical point with a topological charge of +1\begin{document}$ (Q_t=+1) $\end{document} ![]()
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. Moreover, in the RPS formalism, the inclusion of higher-derivative curvature terms in the form of Gauss-Bonnet gravity does not alter the topological classification of critical points in charged AdS black holes.
In this study, we investigate the bulk-boundary and restricted phase space (RPS) thermodynamics of Rissner-Nordström (R-N) AdS and 6-dimensional charged Gauss-Bonnet AdS black holes. Additionally, we examine the topological characteristics of the considered black holes and compare them with the results of extended thermodynamics. We determine that the topological behavior of the bulk-boundary thermodynamics is the same as that of the extended thermodynamics, whereas the RPS thermodynamics exhibits a distinct behavior. Furthermore, we demonstrate that within the RPS formalism, there is only one critical point with a topological charge of +1
2024, 48(9): 095107. doi: 10.1088/1674-1137/ad4c58
Abstract:
In this paper, we analyze inflationary parameters and swampland conjectures in the presence of a scalar field and Chaplygin models. We examine inflationary parameters, such as slow-roll parameters, scalar and tensor power spectra, spectral index, and tensor-to-scalar ratio, in the presence of a scalar field and Chaplygin gas models. We also discuss recently proposed swampland conjectures. We assume that the inflationary expansion is driven by a standard scalar field with a decay ratio Γ that has a generic power-law dependence on the scalar field ϕ and that the temperature of the thermal bath T is given by\begin{document}$\Gamma(\phi,T)= C_{\phi} {T^{a}}/{\phi^{a-1}}$\end{document} ![]()
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, where \begin{document}$C_{\phi}$\end{document} ![]()
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is a dimensionless parameter and a is the inflation decay rate. In a scenario where our model operates within a robust dissipative environment \begin{document}$(R\gg1)$\end{document} ![]()
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, we analyze both fundamental and perturbative dynamics to extract key inflationary parameters. These include the scalar power spectrum \begin{document}${{\cal{P}}_{{\cal{R}}}}$\end{document} ![]()
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, dissipative ratio R, scalar spectral index \begin{document}$n_{s}$\end{document} ![]()
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, tensor-to-scalar ratio r, running of the scalar spectral index \begin{document}$\dfrac{{\rm d}n_{s}}{{\rm d}\ln{k}}$\end{document} ![]()
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, and generalized ratio of the swampland de-Sitter conjecture \begin{document}$\dfrac{T'V}{V'T}$\end{document} ![]()
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for three different potentials.
In this paper, we analyze inflationary parameters and swampland conjectures in the presence of a scalar field and Chaplygin models. We examine inflationary parameters, such as slow-roll parameters, scalar and tensor power spectra, spectral index, and tensor-to-scalar ratio, in the presence of a scalar field and Chaplygin gas models. We also discuss recently proposed swampland conjectures. We assume that the inflationary expansion is driven by a standard scalar field with a decay ratio Γ that has a generic power-law dependence on the scalar field ϕ and that the temperature of the thermal bath T is given by
2024, 48(9): 095108. doi: 10.1088/1674-1137/ad57a5
Abstract:
Using AdS/CFT correspondence, we analyze the holographic Einstein images via the response function of the complex scalar field as a probe wave on an AdS Schwarzschild scalar-tensor-vector gravity (STVG) black hole (BH). We find that the amplitude of the response function\begin{document}$|\langle O\rangle|$\end{document} ![]()
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decreases with increasing values of coupling parameter α and increases with decreasing temperature T. The frequency ω of the wave source also plays a significant role in wave periods; as we increase the values of ω, the periods of waves decrease, indicating that the total response function closely depends on the wave source. Further, we investigate the optical appearance of the holographic images of the BH in bulk. We found that the holographic ring always appears with surrounding concentric stripes when the observer is located at the north pole, and an extremely bright ring appears when the observer is at the position of the photon sphere of the BH. This ring changes into a luminosity-deformed ring or a bright light spot as the observational angle changes. The corresponding brightness profiles show that the luminosity of the ring decreases and the shadow radius increases with increasing values of α. The relation between temperature T and the inverse of the horizon\begin{document}$h_{e}$\end{document} ![]()
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is discussed; T is small at the beginning of the horizon \begin{document}$h_{e}$\end{document} ![]()
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and then increases as the horizon radius increases. This effect can be used to distinguish the STVG BH solution from other BH solutions. Moreover, these significant features are also reflected in the Einstein ring and corresponding brightness profiles. In addition, we compare the results obtained by wave optics and geometric optics, which align well, implying that the holographic scheme adopted in this study is valid.
Using AdS/CFT correspondence, we analyze the holographic Einstein images via the response function of the complex scalar field as a probe wave on an AdS Schwarzschild scalar-tensor-vector gravity (STVG) black hole (BH). We find that the amplitude of the response function
2024, 48(9): 095109. doi: 10.1088/1674-1137/ad57b0
Abstract:
The local topological properties of black hole systems can be expressed through winding numbers as defects. To date, AdS black hole thermodynamics are often depicted by the dual parameters of\begin{document}$ (T,S),\; (P,V), (\Phi, Q) $\end{document} ![]()
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in the extended phase space, while there have been several studies on the black hole thermodynamics in the restricted phase space. In this paper, we analyze the topological properties of charged AdS black holes in the restricted phase space under the higher-dimension and higher-order curvature gravity frame. The results show that the topological number of the charged black hole in the same canonical ensembles is a constant and is independent of the concrete dual thermodynamical parameters. However, the topological number in the grand canonical ensemble is different from that in the canonical ensemble for the same black hole system. Furthermore, these results are independent of dimension d and highest order k of the Lanczos-Lovelock densities.
The local topological properties of black hole systems can be expressed through winding numbers as defects. To date, AdS black hole thermodynamics are often depicted by the dual parameters of
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