We systematically investigate the quasinormal modes of thick branes in $\textit{f}$($\textit{R}$) gravity by numerically solving the Schrödinger-like perturbation equation of gravitational perturbations. To ensure reliability of the results, we employ three complementary methods: the asymptotic iteration method, direct integration of the wave equation, and time-domain numerical evolution. We analyze how model parameters influence the shape of the effective potential of gravitational perturbations and find that the structure of the potential barrier plays a significant role in shaping the quasinormal frequency spectrum. The results obtained from the three methods exhibit strong consistency, thereby ensuring the reliability of the calculations. In particular, real parts of the quasinormal frequencies exhibit an approximately arithmetic progression, suggesting that quasi-localized states can be understood as resonances between the barriers.

China

Yu-Peng E.

Chun-Chun Zhu

Yu-Xiao Liu

Quasinormal modes of thick branes in $\textit{f}$($\textit{R}$) gravity

In this study, we investigate the possibility of enhancing the di-jet resonance searches by tagging the final state radiation (FSR) jet using an event-level deep neural network. It is found that solely relying on the 4-momenta of the leading three jets allows the algorithm to achieve good discriminating power that can identify the hardest FSR jet in the signal while rejecting other soft jets. Once the invariant mass is corrected with the tagged FSR jet, the mass resolution of the signal is greatly enhanced, and the sensitivity of the search is also improved by more than 10%. By crafting the input variables carefully, the algorithm introduces minimal mass sculpting for the background, and its applicability extends to a broad mass range. This work proves that FSR jet tagging can potentially enhance di-jet resonance searches, suiting various stages of the physics programmes at the Large Hadron Collider (LHC) and High-Luminosity LHC (HL-LHC).

Bingxuan Liu

Yuxuan Shen

Yuanshunzi Sui

Enhancing di-jet resonance searches via a final-state radiation jet tagging algorithm * Bingxuan Liu is supported by Shenzhen Campus of the Sun Yat-sen University under project 74140-12255011, and by the Young Scientists Fund (C Class) of the National Natural Science Foundation of China (12405122). Both Yuxuan Shen and Yuanshunzi Sui are supported by College Students’ Innovative Entrepreneurial Training Plan Program

The study of periodic orbits in extreme-mass-ratio inspirals is essential for understanding the dynamics of small bodies orbiting supermassive black holes. In this paper, we study the periodic orbits and their corresponding gravitational wave emissions within the framework of an effective field theory-based extension of general relativity (EFTGR), which incorporates higher-order curvature terms into the Einstein–Hilbert action. We start with a brief analysis of the modified black hole spacetime in EFTGR and examine how its parameters influence the dynamics of a massive neutral particle using the Lagrangian formalism. Focusing on the impact of the higher-order curvature terms in EFTGR, we examine the properties of periodic orbits, which are characterized by three topological integers ($\textit{z}$, $\textit{w}$, $\textit{v}$) that uniquely classify their trajectories. By analyzing these orbits within EFTGR, we aim to provide new insights into how strong-field deviations from general relativity may manifest in observable phenomena. We then calculate the gravitational waveforms generated by these periodic orbits, identifying potential observational signatures. Our analysis reveals a direct connection between the zoom-whirl orbital behavior of the small compact object and the gravitational waveforms it emits: higher zoom numbers lead to increasingly intricate waveform substructures. The results contribute to a clearer understanding of the dynamical features of EFTGR and open new avenues for probing black hole properties via gravitational wave detection.

Shuo Lu

Hao-Jie Lin

Tao Zhu

Xin Zhang

Gravitational radiations from periodic orbits around a black hole in the effective field theory extension of general relativity

In this paper, we investigate the dynamical evolution of the innermost stable circular orbit and light ring of a charged black hole under the influence of scalarization dynamics. This is achieved through a series of nonlinear simulations within the framework of the Einstein–Maxwell-dilaton theory. By combining these nonlinear simulations with a $$3+1$$ approach to geodesics in the dynamical spacetime, we derive the conditions for determining the ISCO and light ring in such a dynamical spacetime. Our results demonstrate how the ISCO and light ring evolve as a ‘hairless’ charged black hole transitions to a scalarized state. Moreover, we find that black hole scalarization leads to an increase in the areal radii of both the ISCO and light ring. These findings provide new insights into black hole scalarization, particularly concerning the dynamical evolution of the ISCO and light ring in a dynamically evolving spacetime.

Yu-Peng Zhang

Shao-Wen Wei

Evolution of innermost stable circular orbit and light ring of a charged black hole induced by the scalarization

In this paper, we explore the feasibility of detecting gravitomagnetic effects generated by gravitational waves, by monitoring the relative orientation of the angular momentum vectors of test particles. We analyze the response of the relative angular momentum direction to all six polarization modes of gravitational waves and estimate the magnitude of its variation during gravitational wave events. Our findings indicate that when test particles possess magnetic moments, applying an external magnetic field of appropriate strength can induce resonant precession of the angular momentum direction under the influence of gravitational waves. This resonance may significantly amplify the gravitational wave signal, potentially enabling its detection with future gyroscope-based detectors. Such detectors would complement existing gravitational wave observatories that rely on gravitoelectric effects.

Yu-Qi Dong

Zhoujian Cao

Gravitational wave detection based on gravitomagnetic effects

Heavy Majorana neutrinos ($\textit{N}$) are predicted in many models of physics beyond the Standard Model. In this work, we explore the production and detection prospects of TeV-scale heavy neutrinos ( $ m_N \gtrsim 1 $ TeV) at a future 3 TeV Compact Linear Collider (CLIC). We focus on two distinct decay topologies: (i) $ N \to \ell^\pm W^\mp $ with hadronic $\textit{W}$ boson decay, leading to a final state with one charged lepton and a hadronic fat jet $ J_W $ ; and (ii) $ N \to \nu h $ with subsequent Higgs decay $ h \to b\bar{b} $ , yielding a Higgs-tagged fat jet $ J_h $ and $\not {E}_T$ . Based on comprehensive detector-level simulations and background analysis, we present both $ 2\sigma $ exclusion limits and $ 5\sigma $ discovery reaches in the $ m_N $ – $ |V_{\ell N}|^2 $ plane. We further extract 95% confidence level upper limits on the mixing parameter $ |V_{\ell N}|^2 $ and perform a detailed comparison with existing constraints from direct searches at future colliders and indirect global fits. Our findings demonstrate that a 3 TeV CLIC can improve the sensitivity to $ |V_{\ell N}|^2 $ by about two orders of magnitude compared with the projected reaches of future hadron colliders while remaining competitive with other CLIC search channels.

Yao-Bei Liu

Jing-Wei Lian

Searches for heavy neutrinos at a 3 TeV CLIC in fat jet final states * Yao-Bei Liu is supported by the Natural Science Foundation of Henan Province, China (252300421988), Jing-Wei Lian is supported by the National Natural Science Foundation of China (12447140) and the Natural Science Foundation of Henan Province, China (252300421771)

The charmed baryon was first observed experimentally in 1975, one year after the charm quark's confirmation via the discovery of the $ J/\psi $ particle. Studying charmed baryon decays provides a pathway to investigate both strong and weak interactions, leveraging the weak decays of the embedded charm quark. However, for approximately three decades following its discovery, experimental knowledge of charmed baryons remained significantly limited compared to those of the hidden-charm $\textit{ψ}$ mesons and open-charm $ D_{(s)} $ mesons. This situation changed markedly starting in 2014, when dedicated data collection for charmed baryons commenced at BESIII. In this article, we review the experimental progress achieved since 2014 in understanding the weak decays of the charmed baryons.

Pei-Rong Li

Xiao-Rui Lyu

Yangheng Zheng

Experimental overview on the charmed baryon decays * The authors thank Fusheng Yu for useful discussions. The authors are supported in part by National Natural Science Foundation of China (12221005, 12422504); CAS Project for Young Scientists in Basic Research (YSBR-117); Fundamental Research Funds for the Central Universities, Lanzhou University (lzujbky-2025-ytB01, lzujbky-2023-stlt01, lzujbky-2023-it32), University of Chinese Academy of Sciences

We investigate the potential of extreme mass-ratio inspirals to constrain quantum Oppenheimer–Snyder black holes within the framework of loop quantum gravity. We consider a stellar-mass object orbiting a supermassive Oppenheimer–Snyder black hole in an equatorial eccentric trajectory. To explore the dynamical behavior of the system, we analyze its orbital evolution under gravitational radiation within the adiabatic approximation and the mass-quadrupole formula for different initial orbital configurations. Our results show that the quantum correction parameter $$\hat{\alpha }$$ slows down the evolution of the orbital semi-latus rectum and eccentricity. We then employ the numerical kludge method to generate the corresponding time-domain gravitational waveforms. To assess detectability, we include Doppler modulation due to the motion of space-based detectors and compute the frequency-domain characteristic strain. By evaluating mismatches between response signals for different values of $$\hat{\alpha }$$ , we show that even small corrections $$( \hat{\alpha } \sim 10^{-5})$$ produce distinguishable effects. Our analysis suggests that future space-based detectors such as LISA can probe quantum gravitational corrections in the strong-field regime and place constraints significantly stronger than those from black hole shadow observations.

Sen Yang

Li Zhao

Constraints on quantum Oppenheimer–Snyder black holes with eccentric extreme mass-ratio inspirals

Electroweak (EW) amplitudes in the gauge-Goldstone five-component formalism have a distinctive property: gauge symmetry is imprinted in the amplitudes, manifested as the massive Ward identity (MWI) $ k^M{\cal{M}}_M=0 $ . In this study, we used the HELAS package to numerically study gauge symmetry in EW amplitudes. First, we directly tested gauge symmetry by examining the MWI of amplitudes. Second, we modified the couplings within a vertex and among vertices to check if and how the MWI changes. Third, we tested gauge symmetry by considering the couplings modified by operators from the standard model effective field theory (SMEFT). Similar to the standard model, there are relations between different couplings that are protected by gauge symmetry. We observed that, if we modify the couplings to deviate from the relations, the MWI is violated. In contrast, the MWI is restored when the relations between couplings reduce to those in the SMEFT.

Wang-Fa Li

Junmou Chen

Qian-Jiu Wang

Zhao-Huan Yu

Numerical study on the gauge symmetry of electroweak amplitudes * Junmou Chen is supported by National Natural Science Foundation of China (12205118), Wang-Fa Li, Qian-Jiu Wang, and Zhao-Huan Yu are supported by the Guangzhou Science and Technology Planning Project (2024A04J4026)

We investigate the “complexity equals anything” proposal with codimension-one and codimension-zero gravitational observables for multi-horizon black holes, using the Bardeen-AdS class black hole as an example. In particular, we compare the results with the “complexity equals volume” (CV) proposal and find that the generalized volume complexitiy enables the probing of a more complete black hole interior, that is, all spacetime regions where the blackening factor $\textit{f}$ ($\textit{r}$) < 0. This is the advantage brought by the flexibility of this holographic complexity conjecture. In addition, we compute the codimension-zero gravitational observables derived from various geometric quantities and show that these constructions can effectively differentiate the distinct interior regions of the black hole.