相关论文: Optimization of RF phase and beam loading distribu…
Precise calibration of the cavity phase signals is necessary for the operation of any particle accelerator. For many systems this requires human in the loop adjustments based on measurements of the beam parameters downstream. Some recent…
A timing system provides high-precision signals to allow the controls over a variety of hardware and software components in the accelerator complex. This is guaranteed by the radio frequency (RF) and trigger signal synchronization for…
Mitigation of beam backgrounds via collimators is critical for the success of the Belle~II experiment at the SuperKEKB electron-positron collider. We report on an improved simulation methodology, which includes a refined physical…
We develop a configuration of radio-frequency (rf) cavities to dramatically improve the performance of slip-stacking. Slip-stacking is an accumulation technique used at Fermilab to nearly double proton intensity by maintaining two beams of…
The analysis of beamstrahlung radiation, emitted from a beam of charged particles due to the electromagnetic interaction with a second beam of charged particles, provides a diagnostic tool that can be used to monitor beam-beam collisions in…
In 2023, we are replacing the LLRF system for the KEK-PF 2.5 GeV ring. The new system is composed of digital boards such as eRTM, AMC, and {\mu}RTM, based on the MTCA.4 standard. In our system, we adopted the non-IQ direct sampling method…
An upgraded asymmetric e+e- flavor factory, SuperKEKB, is planned at KEK. It will deliver a luminosity of 8 x 10^35 cm^-2 s^-1, allowing precision measurements in the flavor sector which can probe new physics well beyond the scales…
The crab-waist collision scheme has been the baseline choice for SuperKEKB and future circular $e^+e^-$ colliders. Achieved through properly phased sextupoles, the crab-waist transform is essential in suppressing beam-beam resonances,…
Belle II is a $B$ factory experiment aiming to start physics data taking in 2017. It is currently being set up at the SuperKEKB accelerator at the KEK facility in Tsukuba (Japan), an asymmetric $e^+e^-$ collider which aims to achieve an…
The SuperKEKB accelerator and the Belle II experiment constitute the second-generation asymmetric energy B-factory. SuperKEKB has recently set a new world record in instantaneous luminosity, which is anticipated to further increase during…
The high design luminosity of the SuperKEKB electron-positron collider will result in challenging levels of beam-induced backgro\ unds in the interaction region. Understanding and mitigating these backgrounds is critical to the success of…
The SuperKEKB accelerator is designed to achieve unprecedented luminosity levels, but this goal is currently hindered by Sudden Beam Loss (SBL) events. These events not only obstruct luminosity improvement but also pose a significant risk…
Many modern and future particle accelerators employ high gradient superconducting RF (SRF) to generate beams of high energy, high intensity and high brightness for research in high energy and nuclear physics, basic energy sciences, etc. In…
The Belle II detector is currently under construction at the SuperKEKB electron-positron high-luminosity collider, that will provide an instantaneous luminosity 40 times higher than that of KEKB. There- fore the Belle-II VerteX Detector…
The CKM angle $\gamma/\phi_{3}$ is the only one that is accessible with tree level decays in a theoretically clean way such that it provides a precision test of $CP$ violation in the standard model. The Belle II experiment is a substantial…
The Belle II experiment at the SuperKEKB collider is an upgrade of the Belle / KEKB experiment. It will start physics data taking from 2018 and with $40$ times luminosity, its goal is to accumulate 50 $ab^{-1}$ of $e^+e^-$ collision data.…
KEK electron linac was upgraded to 8 GeV for the KEK B-Factory (KEKB) project. During the commissioning of the upgraded linac, even continuing SOR ring injections, we had achieved a primary electron beam with 10-nC (6.24 x 10^10) per bunch…
The FCC-ee accelerator is considered within the FCC design study as a possible first step towards the ultimate goal of a 100 TeV hadron collider. It is a high luminosity e+e- storage ring collider, designed to cover energies of around 90,…
The CKM angle $ \phi_{3} $ is the only angle of the unitarity triangle that is accessible with tree-level decays in a theoretically clean way. The Belle II experiment is a substantial upgrade of the Belle detector and will operate at the…
Crab cavities have been installed in the KEKB B--Factory rings to compensate the crossing angle at the collision point and thus increase luminosity. The beam operation with crab crossing has been done since February 2007. This is the first…