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Title: Transverse phase space diagnostics for ionization injection in laser plasma acceleration using permanent magnetic quadrupoles

We report the transverse phase space diagnostics for electron beams generated through ionization injection in a laser-plasma accelerator. Single-shot measurements of both ultimate emittance and Twiss parameters are achieved by means of permanent magnetic quadrupole. Beams with emittance of μm rad level are obtained in a typical ionization injection scheme, and the dependence on nitrogen concentration and charge density is studied experimentally and confirmed by simulations. A key feature of the transverse phase space, matched beams with Twiss parameter α T ≃ 0, is identified according to the measurement. Lastly, numerical simulations that are in qualitative agreement with the experimental results reveal that a sufficient phase mixing induced by an overlong injection length leads to the matched phase space distribution.
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  1. Tsinghua Univ., Beijing (China). Dept. of Engineering Physics
  2. Univ. of California, Los Angeles, CA (United States)
  3. Univ. of California, Los Angeles, CA (United States); SLAC National Accelerator Lab., Menlo Park, CA (United States)
Publication Date:
Grant/Contract Number:
AC02-76SF00515; 11375006; 11425521; 11475101; 11535006; 11775125
Accepted Manuscript
Journal Name:
Plasma Physics and Controlled Fusion
Additional Journal Information:
Journal Volume: 60; Journal Issue: 4; Journal ID: ISSN 0741-3335
IOP Science
Research Org:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org:
USDOE; National Natural Science Foundation of China (NNSFC)
Country of Publication:
United States
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; emittance; phase space; Twiss parameter; permanent magnetic quadrupole; laser plasma accelerator
OSTI Identifier: