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Genliang Li

Publications and source records attributed to Genliang Li.

3 recordsLinked to original sources

Constraint on environments with eccentric extreme-mass-ratio inspirals: Bayesian inference and Fisher-matrix for dark-matter spikes

Extreme-mass-ratio inspirals (EMRIs) provide sensitive probes of the astrophysical environments surrounding massive black holes. We investigate the inference of dark-matter (DM) spikes with eccentric EMRI gravitational waves within the analytic-kludge waveform framework, including DM-induced dynamical friction and accretion in the secular orbital evolution. We perform Bayesian parameter estimation using Markov-chain Monte Carlo sampling, complemented by Fisher-matrix analyses. We find that steeper DM spikes produce stronger accumulated waveform modifications and substantially improve the measurement of the spike slope $\alpha_{\rm DM}$. More importantly, the constraints exhibit a nonmonotonic dependence on orbital eccentricity. At moderate eccentricity, higher harmonics help break the degeneracy between $e_{\rm LSO}$ and $\alpha_{\rm DM}$, whereas this correlation can persist or the parameter recovery can deteriorate for highly eccentric systems. These results demonstrate that the harmonic structure of eccentric EMRIs can provide valuable information for probing DM distributions around massive black holes with future LISA observations.

gr-qc

A multi-strategy improved snake optimizer for three-dimensional UAV path planning and engineering problems

Metaheuristic algorithms have gained widespread application across various fields owing to their ability to generate diverse solutions. One such algorithm is the Snake Optimizer (SO), a progressive optimization approach. However, SO suffers from the issues of slow convergence speed and susceptibility to local optima. In light of these shortcomings, we propose a novel Multi-strategy Improved Snake Optimizer (MISO). Firstly, we propose a new adaptive random disturbance strategy based on sine function to alleviate the risk of getting trapped in a local optimum. Secondly, we introduce adaptive Levy flight strategy based on scale factor and leader and endow the male snake leader with flight capability, which makes it easier for the algorithm to leap out of the local optimum and find the global optimum. More importantly, we put forward a position update strategy combining elite leadership and Brownian motion, effectively accelerating the convergence speed while ensuring precision. Finally, to demonstrate the performance of MISO, we utilize 30 CEC2017 test functions and the CEC2022 test suite, comparing it with 11 popular algorithms across different dimensions to validate its effectiveness. Moreover, Unmanned Aerial Vehicle (UAV) has been widely used in various fields due to its advantages of low cost, high mobility and easy operation. However, the UAV path planning problem is crucial for flight safety and efficiency, and there are still challenges in establishing and optimizing the path model. Therefore, we apply MISO to the UAV 3D path planning problem as well as 6 engineering design problems to assess its feasibility in practical applications. The experimental results demonstrate that MISO exceeds other competitive algorithms in terms of solution quality and stability, establishing its strong potential for application.

cs.RO

Intensity Effect of Laser-assisted Double Ionization of Helium Atoms by Ultrashort XUV Pulses

We investigate the laser-assisted single XUV photon double ionization of ground state helium. By solving full six-dimensional time-dependent schr{ö}dinger equation, we study the correlation and angular distribution. The discussion in joint energy and angular distributions reveals the competition in odd and even parity double ionization processes in the presence of weak laser field. The emission angle between two photoelectrons can be adjusted by the laser parameters. We depicts how the laser field enhance and/or enable the back-to-back and side-by-side emission of double ionization.

physics.atom-ph