Dephasingless laser wakefield acceleration (DLWFA), a novel laser wakefield acceleration concept based on the recently demonstrated “flying focus” technology, offers a new paradigm in laser-plasma acceleration that could advance the progress toward a TeV linear accelerator using a single-stage system without guiding structures. The recently proposed NSF OPAL laser facility could be the transformative technology that enables this grand challenge in laser-plasma acceleration. We review the viable parameter space for DLWFA based on the scaling of its performance with laser and plasma parameters, and we compare that performance to traditional laser wakefield acceleration. These scalings indicate the necessity for ultrashort, high-energy laser architectures such as NSF OPAL to achieve groundbreaking electron energies using DLWFA. Initial results from MTW-OPAL, the platform for the 6-J DLWFA demonstration experiment, show a tight, round focal spot over a distance of 3.7 mm. New particle-in-cell simulations of that platform indicate that using hydrogen for DLWFA reduces the amount of laser light that is distorted due to refraction at ionization fronts. An experimental path, and the computational and technical design work along that path, from the current status of the field to a single-stage, 100-GeV electron beam via DLWFA on NSF OPAL is outlined. Progress along that path is presented.
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Characterization of meter-scale Bessel beams for plasma formation in a plasma wakefield accelerator
A large challenge with Plasma Wakefield Acceleration lies in creating a plasma with a profile and length that properly match the electron beam. Using a laser-ionized plasma source provides control in creating an appropriate plasma density ramp. Additionally, using a laser-ionized plasma allows for an accelerator to run at a higher repetition rate. At the Facility for Advanced Accelerator Experimental Tests, at SLAC National Accelerator Laboratory, we ionize hydrogen gas with a 225 mJ, 50 fs, 800 nm laser pulse that passes through an axicon lens, imparting a conical phase on the pulse that produces a focal spot with an intensity distribution described radially by a Bessel function. This paper overviews the diagnostic tests used to characterize and optimize the focal spot along the meter-long focus. In particular, we observe how wavefront aberrations in the laser pulse impact the peak intensity of the focal spot. Furthermore, we discuss the impact of nonlinear effects caused by a 6 mm, CaF2 vacuum window in the laser beam line.
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- Award ID(s):
- 2012549
- PAR ID:
- 10526588
- Editor(s):
- Pilat, Fulvia; Fischer, Wolfram; Saethre, Robert; Anisimov, Petr; Andrian, Ivan
- Publisher / Repository:
- JACoW Publishing
- Date Published:
- ISSN:
- 2673-5490
- ISBN:
- 978-3-95450-247-9
- Subject(s) / Keyword(s):
- Accelerator Physics mc6-beam-instrumentation-controls-feedback-and-operational-aspects - MC6: Beam Instrumentation, Controls, Feedback, and Operational Aspects MC6.T25 - MC6.T25 Lasers
- Format(s):
- Medium: X Size: 1865-1868 pages; 1.9 MB Other: PDF
- Size(s):
- 1865-1868 pages 1.9 MB
- Right(s):
- Creative Commons Attribution 4.0 International
- Sponsoring Org:
- National Science Foundation
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