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We present results from two new techniques for the generation of meter-scale, low density (∼1017 cm−3 on axis) plasma waveguides, the “two-Bessel” technique, and the “self-waveguiding” technique. Plasma waveguides of this density and length range are needed for demonstration of a ∼10 GeV laser wakefield accelerator module, key for future staging for a ∼TeV lepton collider. Both techniques require the use of high quality ultrashort pulse Bessel beams to efficiently and uniformly ionize hydrogen gas in meter-scale supersonic gas jets via optical field ionization. We review these two techniques, describe our meter-scale gas jets, and present a new method for correction of optical aberrations in Bessel beams. Finally, we briefly present results from recent experiments employing one of our techniques, demonstrating quasi-monoenergetic acceleration of ∼5 GeV electron bunches in 20 cm long, low density plasma waveguides.
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This content will become publicly available on April 1, 2026
Meter-scale supersonic gas jets for multi-GeV laser-plasma accelerators
Pushing the high energy frontier of laser wakefield electron acceleration to 10 GeV and beyond requires extending the propagation of relativistic intensity pulses to ∼1 m in a low density (Ne ∼ 1017 cm−3) plasma waveguide. We present the development and characterization of two types of supersonic gas jets for meter-scale multi-GeV laser wakefield accelerators. The first type is a 30-cm long single-module gas jet, which demonstrates good axial uniformity using hydrogen. The second type is a modular jet composed of multiple 11-cm-long modules. Longitudinal density profile control is demonstrated with a 2-module (22 cm long) hydrogen jet using gas valve trigger timing. A 1.0-m-long jet is then assembled from nine modules, and generation of 1.0-m long hydrogen plasma is demonstrated using a femtosecond Bessel beam. To our knowledge, this is the longest gas jet laser plasma yet generated.
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- Award ID(s):
- 2010511
- PAR ID:
- 10617445
- Publisher / Repository:
- AIP
- Date Published:
- Journal Name:
- Review of Scientific Instruments
- Volume:
- 96
- Issue:
- 4
- ISSN:
- 0034-6748
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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