Ion acceleration in electrostatic collisionless shock: on the optimal density profile for quasi-monoenergetic beams. (1st February 2018)

• Record Type: Journal Article
• Authors: Boella, E; Fiúza, F; Novo, A Stockem; Fonseca, R; Silva, L O
• Is Part Of: Plasma physics and controlled fusion. Volume 60:Number 3(2018:Mar.)
• Publication Date: 2018-02-01
• Subjects: collisionless shock wave acceleration -- electrostatic shocks -- laser-driven shock acceleration -- compact accelerators -- PIC simulations; 52.35.Tc -- 41.65.Jv -- 52.38.-r -- 52.65.Rr; Plasma (Ionized gases) -- Periodicals; Controlled fusion -- Periodicals; 530.44
• DOI: 10.1088/1361-6587/aaa556
• Languages: English
• ISSNs: 0741-3335

Abstract

Abstract: A numerical study on ion acceleration in electrostatic shock waves is presented, with the aim of determining the best plasma configuration to achieve quasi-monoenergetic ion beams in laser-driven systems. It was recently shown that tailored near-critical density plasmas characterized by a long-scale decreasing rear density profile lead to beams with low energy spread (Fiúza et al 2012 Phys. Rev. Lett. 109 215001). In this work, a detailed parameter scan investigating different plasma scale lengths is carried out. As result, the optimal plasma spatial scale length that allows for minimizing the energy spread while ensuring a significant reflection of ions by the shock is identified. Furthermore, a new configuration where the required profile has been obtained by coupling micro layers of different densities is proposed. Results show that this new engineered approach is a valid alternative, guaranteeing a low energy spread with a higher level of controllability.