arXiv subjects

Ching-En Lin

Publications and source records attributed to Ching-En Lin.

3 recordsLinked to original sources

arXiv2026

Magnetizing nonlinear plasma wakefields for positron acceleration

It is known that only a narrow plasma wakefield sliver in the electron-beam-driven blowout regime suits positron acceleration. Using 3D simulations, we show that matching the cyclotron frequency $\omega_{c}$ with the plasma frequency $\omega_{p}$ forms a stable electron column on axis, expanding the suitable phase space for positron acceleration sizably. For a plasma density $n_p = 10^{16}\text{ cm}^{-3}$ in a 35 T field, the interval expands 4.3 times, and a witness positron beam gains 100--150 MeV over 6 cm ($1.6$--$2.5$~GeV/m) with a 92\% capture rate.

physics.acc-ph↗

arXiv2024

Characterization of Supersonic Jet and Shock Wave with High-Resolution Quantitative Schlieren Imaging

This paper presents an enhanced optical configuration for a single-pass quantitative Schlieren imaging system that achieves an optical resolution of approximately 4.6 micrometers. The modified setup decouples sensitivity from resolution, enabling independent optimization of these critical parameters. Using this high-resolution system, we conduct quantitative analyses of supersonic jets emitted from sub-millimeter nozzles into the atmosphere and investigate shock waves induced by knife blades interacting with these jets in a vacuum environment. The fine resolution allows for detailed visualization of shock wave structures and accurate measurement of density gradients. We demonstrate the system's effectiveness by examining the density gradient profile along the shock diamonds and mapping density profiles across shock waves. These density profiles are analyzed for their relevance in laser-plasma applications, including laser wakefield acceleration and the Analog Black Hole Evaporation via Laser (AnaBHEL) experiment. Our findings indicate that this system can help determine key parameters such as peak density, plateau length, and shock wave thickness-essential for optimizing electron acceleration and achieving specific plasma density profiles. This high-resolution quantitative Schlieren imaging technique thus serves as a valuable tool for exploring complex fluid dynamics and supporting advancements in laser-plasma physics research.

physics.optics↗

arXiv2022

AnaBHEL (Analog Black Hole Evaporation via Lasers) Experiment: Concept, Design, and Status

Accelerating relativistic mirror has long been recognized as a viable setting where the physics mimics that of black hole Hawking radiation. In 2017, Chen and Mourou proposed a novel method to realize such a system by traversing an ultra-intense laser through a plasma target with a decreasing density. An international AnaBHEL (Analog Black Hole Evaporation via Lasers) Collaboration has been formed with the objectives of observing the analog Hawking radiation and shedding light on the information loss paradox. To reach these goals, we plan to first verify the dynamics of the flying plasma mirror and to characterize the correspondence between the plasma density gradient and the trajectory of the accelerating plasma mirror. We will then attempt to detect the analog Hawking radiation photons and measure the entanglement between the Hawking photons and their "partner particles". In this paper, we describe our vision and strategy of AnaBHEL using the Apollon laser as a reference, and we report on the progress of our R&D of the key components in this experiment, including the supersonic gas jet with a graded density profile, and the superconducting nanowire single-photon Hawking detector. In parallel to these hardware efforts, we performed computer simulations to estimate the potential backgrounds, and derive analytic expressions for modifications to the blackbody spectrum of Hawking radiation for a perfectly reflecting, point mirror, due to the semit-ransparency and finite-size effects specific to flying plasma mirrors. Based on this more realistic radiation spectrum, we estimate the Hawking photon yield to guide the design of the AnaBHEL experiment, which appears to be achievable.

gr-qc↗