arXiv subjects

Meiyu Si

Publications and source records attributed to Meiyu Si.

6 recordsLinked to original sources

arXiv2025

Estimation of the Inverse Compton Scattering Background in MeV Gamma-Gamma Collider

The MeV Gamma-Gamma Collider would provide a direct experimental platform for elastic light-by-light scattering ($\gamma\gamma \to \gamma\gamma$) and the Breit-Wheeler process with two real photons ($\gamma\gamma \to e^+e^-$). A Monte Carlo code, the Genie Background Evaluation Tool (GBET), has been developed to fully simulate two successive inverse Compton scatterings in the linear regime, including $e^- + \text{laser} \to e^-+ \gamma$ and $e^- + \gamma \rightarrow e^- + \gamma$. GBET overcomes the inherent information loss in traditional luminosity-spectrum-based chain simulations, preserving full particle-level information and achieving higher physical fidelity. The effectiveness of the code is verified by benchmarking against the simulation results of CAIN. GBET shows that the event rate of background photons generated by the first inverse Compton scattering is $6.24 \times 10^7$/s, with energies below 18 eV; the second inverse Compton scattering generates background electrons at 51.99/s and photons at 0.99/s, both with energies below 11 MeV. In addition, M{\o}ller scattering contributes background electrons at 0.56/s with energies around 200 MeV. The count rates of background electrons and positrons originating from the Breit-Wheeler process are 1312.2/s and 1314.3/s, respectively, with energy distributions ranging from 511 to 720 keV.

physics.ins-det↗

arXiv2024

Stable radiation field positron acceleration in a micro-tube

Nowadays, there is a desperate need for an ultra-acceleration-gradient method for antimatter particles, which holds great significance in exploring the origin of matter, CP violation, astrophysics, and medical physics. Compared to traditional accelerators with low gradients and a limited acceleration region for positrons in laser-driven charge separation fields, we propose an innovative high-gradient positron acceleration mechanism with implementation advantages. Injecting a relativistic electron beam into a dense plasma micro-tube generates a stable and periodic high-intensity mid-infrared radiation (mid-IR) field, reaching tens of GV/m. This field, propagating synchronously with the electron beam, achieves a 1 GeV energy gain for the positron bunch within 140 picoseconds with a minimal energy spread-approximately 1.56% during a stable phase. By utilizing continuous mid-IR, the efficiency of energy transfer from the electron beam to either a single positron bunch or three positron bunches simultaneously could reach up to 20% and 40%, respectively. This acceleration scheme can achieve cascaded acceleration for a single positron bunch and series acceleration for multiple positron bunches in a continuous, stable, and efficient manner.

physics.plasm-ph↗

arXiv2024

Research progress on advanced positron acceleration

Plasma wakefield acceleration (PWFA) is a promising method for reducing the scale and cost of future electron-positron collider experiments by using shorter plasma sections to enhance beam energy. While electron acceleration has already achieved breakthroughs in theory and experimentation, generating high-quality positron beams in plasma presents greater challenges, such as controlling emittance and energy spread, improving energy conversion efficiency, and generating positron sources. In this paper, we have summarized the research progress on advanced positron acceleration schemes, including particle beam-driven wakefield acceleration, laser-driven wakefield acceleration, radiation-based acceleration, hollow plasma channels, among others. The strengths and weaknesses of these approaches are analyzed, and the future outlook is discussed to drive experimental advancements.

physics.acc-ph↗

arXiv2023

High energy beam energy measurement with microwave-electron Compton backscattering

The uncertainty of the energy measurement of the electron beam on circular electron positron collider (CEPC) must be smaller than 10$\mathrm{MeV}$ to make sure the accurate measurement of the mass of the Higgs boson. In order to simplify the energy measurement system, a new method is proposed by fitting the Compton edge of the energy distribution of the gamma ray from a microwave-electron Compton scattering. With our method, the uncertainty of the energy measurement is 6$\mathrm{MeV}$ for the electron energy of $120\mathrm{GeV}$ in the Higgs mode. In this system, the energy resolution of the gamma detection needs to reach $10^{-4}$. Therefore, only the high-purity germanium (HPGe) detector can meet the critical requirement. In a head-on collision mode, the initial photons should be microwave photons with the wavelength of 3.04 centimeters. A cylindrical resonant cavity with selected ${TM_{010}}$ mode is used to transmit microwaves. After the microwave-electron Compton backscattering, the scattered photons and the synchrotron-radiation background transmit a shielding structure and then are detected by a HPGe detector at the end of the beam line of the synchrotron-radiation applications. The hole radius in the side wall of the cavity is about $1.5\mathrm{mm}$ to allow the electron beam passing through. The results of the computer simulation technology (CST) software shows that the influence of the hole radius on the cavity field is negligible. The change of the resonance frequency can be easily corrected by fine-tuning the cavity size.

hep-ex↗

arXiv2023

The linear and nonlinear inverse Compton scattering between microwaves and electrons in a resonant cavity

The new scheme of the energy measurement of the extremely high energy electron beam with the inverse Compton scattering between electrons and microwave photons requires the precise calculation of the interaction cross section of electrons and microwave photons in a resonant cavity. In the local space of the cavity, the electromagnetic field is expressed by Bessel functions. Although Bessel functions can form a complete set of orthogonal basis, it is difficult to quantify them directly as fundamental wave functions. Fortunately, with the Fourier expansion of Bessel functions, the local electromagnetic field can be considered as the superposition of a series of plane waves. Therefore, with corresponding corrections of the cross section formula of the classical Compton scattering, the cross section of the linear or nonlinear microwave Compton scattering in the local space can be described accurately. As an important application of our results in astrophysics, corresponding ground verification devices can be designed to perform experimental verifications on the prediction of the Sunyaev-Zeldovich (SZ) effect of the cosmic microwave background radiation. Our results could also provide a new way to generate wave sources with strong practical value, such as the terahertz waves, the ultra-violet (EUV) waves, or the mid-infrared beams.

physics.plasm-ph↗

arXiv2022

Light Dark Matter Axion Detection with Static Electric Field

We explore the axionic dark matter search sensitivity with a narrow-band detection scheme aiming at the axion-photon conversion by the static electric field inside a cylindrical capacitor. An alternating magnetic field signal is induced by effective currents as the axion dark matter flows perpendicularly through the electric field. At low axion masses, like in a KKLT scenario, front-end narrow band filtering is provided by using LC resonance with a high $Q$ factor, which enhances the detectability of the tiny magnetic field signal and also leads to a thermal noise as the major background that can be reduced at cryogenic conditions. We demonstrate that high $g_{aγ}$ sensitivity can be achieved by using a strong electric field. The QCD axion theoretical parameter space can be reached with high $E\sim$ GVm$^{-1}$ field strength. Using the static electric field scheme essentially avoids exposing the sensitive superconducting pickup to an applied laboratory magnetic field.

hep-ph↗