arXiv subjects

Giovanni Zevi Della Porta

Publications and source records attributed to Giovanni Zevi Della Porta.

4 recordsLinked to original sources

arXiv2025

Wakefield regeneration in a resonantly driven plasma accelerator

Plasma wakefields offer high acceleration gradients, orders of magnitude larger than conventional RF accelerators. However, the achievable luminosity remains relatively low, typically limited by repetition rate and the charge accelerated per shot. In this work, we show that a train of drive bunches can be harnessed to accelerate multiple witness bunches in a single shot. We demonstrate that periodically loading the wakefields removes the limit on the energy transfer from the drive beam to the plasma, which allows the luminosity to be increased. Proof-of-concept simulations for the AWAKE scheme are carried out to demonstrate the technique, achieving a doubling of the accelerated charge while exploiting only a fraction of the drive train.

physics.acc-ph↗

arXiv2022

Automatic setup of 18 MeV electron beamline using machine learning

To improve the performance-critical stability and brightness of the electron bunch at injection into the proton-driven plasma wakefield at the AWAKE CERN experiment, automation approaches based on unsupervised Machine Learning (ML) were developed and deployed. Numerical optimisers were tested together with different model-free reinforcement learning agents. In order to avoid any bias, reinforcement learning agents have been trained also using a completely unsupervised state encoding using auto-encoders. To aid hyper-parameter selection, a full synthetic model of the beamline was constructed using a variational auto-encoder trained to generate surrogate data from equipment settings. This paper describes the novel approaches based on deep learning and reinforcement learning to aid the automatic setup of a low energy line, as the one used to deliver beam to the AWAKE facility. The results obtained with the different ML approaches, including automatic unsupervised feature extraction from images using computer vision are presented. The prospects for operational deployment and wider applicability are discussed.

physics.acc-ph↗

arXiv2022

Design of the AWAKE Run 2c transfer lines using numerical optimizers

The Advanced Wakefield (AWAKE) Experiment is a proof-of-principle experiment demonstrating the acceleration of electron beams via proton-driven plasma wakefield acceleration. AWAKE Run 1 achieved acceleration of electron beams to 2 GeV and the intention for Run 2 is to build on these results by achieving acceleration to ~10 GeV with a higher beam quality. As part of the upgrade to Run 2, the existing proton and electron beamlines will be adapted and a second plasma cell and new 150 MeV electron beamline will be added. This new beamline will be required to inject electron bunches with micron-level beam size and stability into the second plasma cell from within the 1 m gap between the two plasma cells. In this paper we describe the techniques used (e.g. numerical optimizers and genetic algorithms) to produce the design of the 150 MeV electron line in order to meet the challenging experimental specifications. Operational techniques are also studied for both electron transfer lines including steering and alignment methods utilising numerical optimizers and beam measurement techniques employing neural networks.

physics.acc-ph↗

arXiv2020

Recent highlights and plans of the AWAKE experiment

The Advanced Wakefield Experiment (AWAKE) is an accelerator R&D experiment at CERN using, for the first time, a high-energy proton bunch to drive wakefields in plasma and accelerating electrons to the GeV energy scale. The principle of the AWAKE experiment is described. We show experimental results of the seeded self-modulation process of the long 400 GeV SPS proton bunch, transforming the bunch into a train of micro-bunches and driving resonantly the wakefields in the 10 m long Rb plasma. We also show that externally-injected electrons can be accelerated by these wakefields to several GeV. The next steps of the AWAKE experimental program are shown. Possible first applications to high-energy physics experiments, where the scheme takes advantage of the large energy stored in the proton bunch to reach very high energy gain in a single plasma, are described.

physics.acc-ph↗