加速器物理
Precise alignment of the undulator trajectory onto a straight line is a per-requisite for high fidelity SASE operation, which in turn also enables non-standard operation modes like self-seeding or two-color operation. At European XFEL…
Simultaneously maximizing power-transfer efficiency and preserving beam quality in plasma-based accelerators is constrained by the transverse beam breakup instability. We present an analytical transverse wake model derived from the plasma…
The 7th ALEGRO workshop, hosted by INFN Frascati National Laboratories from 3rd to 5th March 2026, brought together the international Advanced Novel Accelerators (ANA) community to discuss the role of advanced wakefield accelerators (AWA)…
We propose a phase space manipulation involving one energy modulation sandwiched by two dispersion sections which converts a bunched particle beam or bunch train to ultra-high-harmonic density modulation, while the energy modulation in…
A synchrotron injection scheme for the SuperKEKB electron high-energy ring (HER) was implemented and experimentally evaluated as the first attempt with a top-up injection during beam collisions. The lattice at the HER injection point was…
Plasma accelerators now produce GeV-class electron beams with brightness and stability sufficient to drive free-electron lasers. Beyond this, they possess a unique yet largely unexplored capability: shaping the phase space of the beam in…
Plasma accelerators sustain gradients orders of magnitude higher than conventional radiofrequency machines, but most proposed paths to TeV energies still require tens of stages, each demanding sub-micrometer alignment, femtosecond…
Precise measurement of the beam sigma matrix is essential for matching the optics in transport lines and ensuring reliable accelerator operation. In this work, we present a method for measuring and reconstructing the non-temporal…
Inverse Compton X-ray sources are laboratory-scale devices providing quasi-monochromatic synchrotron radiation which is generated by laser photons Compton-scattering off highly relativistic electrons. Since the shape and width of the X-ray…
For many synchrotrons which cross $\gamma_t$ transition, a high intensity threshold has been identified beyond which significant beam losses are observed. These losses are due to a high-intensity mode coupling instability, which can be…
Beam-excited resonant modes in RF cavities are important sources of beam-coupling impedance and coupled-bunch instabilities in high-current storage rings. We develop a unified framework for longitudinal and transverse resonant impedances…
Nonlinear Compton scattering enables sources of intense high-energy radiation. However, predicting source-level spectra for realistic electron beams typically requires computationally expensive trajectory-based calculations, whereas…
Exceptionally, a bunched electron beam can get trapped by its own spontaneously emitted synchrotron undulator radiation in the self-interaction scheme of TES (Tapering Enhanced Superradiance). In this scheme, excess radiative energy is…
We demonstrate a versatile platform for high-power attosecond soft X-ray pulse generation with polarization and photon energy control at the SwissFEL free-electron laser. An isolated high-current spike embedded within a long electron-beam…
Thin carbon-strip targets provide fast relative hadron beam polarimetry, but their response in intense relativistic bunched beams is not governed by local stopping-power heating alone. We develop a coupled response model that combines…
Lambertson method is a classical approach that can indirectly measure the electrical center offset in the beam position monitor (BPM) due to imperfections in the pickup buttons. It applies to BPMs that are symmetric in both the horizontal…
The Mu2e experiment has a stringent requirement for extinction of the pulsed proton beam, referring to the elimination of particles between proton bunches to a relative level of 10$^-10$, which means a single out-of-time particle in the…
A critical review of the methodology used in F. Rathmann et al., Phys. Rev. Accel. Beams 29, 021001 (2026), to evaluate beam-induced depolarization of the Atomic Polarized Hydrogen Gas Jet (HJET) target at the Electron--Ion Collider (EIC)…
Externally seeded free-electron lasers (FELs) are promising approaches for generating fully coherent soft-X-ray radiation. Their extension to shorter wavelengths and MHz-level repetition rates is, however, constrained by the limited…
Following the Future Circular Collider (FCC) Feasibility Study completion, the impedance model for the FCC-ee High-Energy Booster (HEB) has been significantly expanded beyond the initial copper vacuum pipe resistive wall analysis. This…