加速器物理
Magnetic flux trapping in the Meissner transition of superconducting radio frequency cavities can substantially increase dissipation which impacts cryogenic costs and necessitates expensive magnetic shielding. Recent findings point at the…
We investigate the superheating fields $H_{sh}$ of semi-infinite superconductors and layered superconductors in the diffusive limit by using the well-established quasiclassical Green's function formalism of the BCS theory. The coupled…
This document presents in detail the derivation of the formulas that describe the resonance driving terms and the tune spread with amplitude generated by the beam-beam long range interactions and the DC wire compensators in cyclical…
Since the initial development of charged particle colliders in the middle of the 20th century, these advanced scientific instruments have been at the forefront of scientific discoveries in high energy physics. Collider accelerator…
This article presents a method that uses turn-by-turn beam position data and k-modulation data to measure the calibration factors of beam position monitors in high energy accelerators. In this method, new algorithms have been developed to…
Our objective will be to integrate ML into Fermilab accelerator operations and furthermore provide an accessible framework which can also be used by a broad range of other accelerator systems with dynamic tuning needs. We will develop of…
A consistent theory, which describes the incoherent scattering of classically moving relativistic particles by the nuclei of crystal planes without any phenomenological parameter is presented. The basic notions of quantum mechanics are…
Laser plasma acceleration at kilohertz repetition rate has recently been shown to work in two different regimes, with pulse lengths of either 30 fs or 3.5 fs. We now report on a systematic study in which a large range of pulse durations and…
Ionization profile monitors (IPMs) are widely used in particle accelerators for fast evaluation of parameters of high energy beams. Due to the space-charge effects and several other physical reasons, as well as due to instrumental effects,…
Vertical excursion fixed-field alternating gradient accelerators can be designed with tunes that are invariant with respect to momentum and trajectories that are scaled images of each other displaced only in the vertical direction. This is…
The spectroscopic techniques for time-resolved fine analysis of matter require coherent X-ray radiation with femtosecond duration and high average brightness. Seeded free-electron lasers (FELs), which use the frequency up-conversion of an…
In this paper, we discuss effects of space charge fields on imaging performance in a single shot time-resolved electron microscope (TEM). Using a Green's function perturbation method, we derive analytical estimates for the effects of space…
Flat-beam transforms (FBTs) provide a technique for controlling the emittance partitioning between the beam's two transverse dimensions. To date, nearly all FBT studies have been in regimes where the beam's own space-charge effects can be…
Prior to establishing operation of the world's first mulit-turn superconducting Energy Recovery Linac, (ERL) the Cornell-BNL Energy Recovery Test Accelerator (CBETA) was configured for one turn energy recovery. In this setup, direct…
Multipactor discharges are widely observed in the accelerator field, and their suppression has been studied to improve accelerator performance. A dielectric-assist accelerating (DAA) cavity is a standing-wave accelerating cavity that…
We derived S-parameter based expressions for the intrinsic quality factor of an arbitrary coupled multiport microwave cavity and non-ideal test fixture. Practical accuracy limitations of the obtained expressions specifically for…
Reported here is the first demonstration of electron beam generation in an SRF TESLA 1.3 GHz gun equipped with field emission cathode when operated at 2 Kelvin. The cathode is submicron film of nitrogen-incorporated ultrananocrystalline…
Characterization and control of the transverse phase space of high-brightness electron beams is required at free-electron lasers or electron diffraction experiments for emittance measurement and beam optimization as well as at advanced…
We demonstrate a compact technique to compress electron pulses to attosecond length, while keeping the energy spread reasonably small. The technique is based on Dielectric Laser Acceleration (DLA) in nanophotonic silicon structures. Unlike…
We derive the transfer function of a multicell cavity with parasitic same-order modes (from power coupler to pickup probe). The derived model is discussed and compared to measurement data.