skip to main content


Title: Optimizing beam transport in rapidly compressing beams on the neutralized drift compression experiment – II

The Neutralized Drift Compression Experiment-II (NDCX-II) is an induction linac that generates intense pulses of 1.2 MeV helium ions for heating matter to extreme conditions. Here, we present recent results on optimizing beam transport. The NDCX-II beamline includes a 1-m-long drift section downstream of the last transport solenoid, which is filled with charge-neutralizing plasma that enables rapid longitudinal compression of an intense ion beam against space-charge forces. The transport section on NDCX-II consists of 28 solenoids. Finding optimal field settings for a group of solenoids requires knowledge of the envelope parameters of the beam. Imaging the beam on the scintillator gives the radius of the beam, but the envelope angle is not measured directly. We demonstrate how the parameters of the beam envelope (radius, envelop angle, and emittance) can be reconstructed from a series of images taken by varying the B-field strengths of a solenoid upstream of the scintillator. We use this technique to evaluate emittance at several points in the NDCX-II beamline and for optimizing the trajectory of the beam at the entry of the plasma-filled drift section.
 [1] ;  [2] ;  [2] ;  [3] ;  [4] ;  [4] ;  [3] ;  [4] ;  [4] ;  [4]
  1. Univ. of Washington, Seattle, WA (United States)
  2. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
  3. Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
  4. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Publication Date:
Grant/Contract Number:
AC02-05CH11231; AC0205CH11231; AC52-07NA27344; AC02-09CH11466
Published Article
Journal Name:
Matter and Radiation at Extremes
Additional Journal Information:
Journal Volume: 3; Journal Issue: 2; Journal ID: ISSN 2468-080X
Science and Technology Information Center, China Academy of Engineering Physics; Elsevier
Research Org:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org:
USDOE Office of Science (SC), Fusion Energy Sciences (FES) (SC-24)
Country of Publication:
United States
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1458509