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Title: DOE-HEP Final Report for 2013-2016: Studies of plasma wakefields for high repetition-rate plasma collider, and Theoretical study of laser-plasma proton and ion acceleration

Abstract

There were two goals for this funded project: 1. Studies of plasma wakefields for high repetition-rate plasma collider, and 2. Theoretical study of laser-plasma proton and ion acceleration. For goal 1, an analytical model was developed to determine the ion-motion resulting from the interaction of non-linear “blow-out” wakefields excited by beam-plasma and laser-plasma interactions. This is key to understanding the state of the plasma at timescales of 1 picosecond to a few 10s of picoseconds behind the driver-energy pulse. More information can be found in the document. For goal 2, we analytically and computationally analyzed the longitudinal instabilities of the laser-plasma interactions at the critical layer. Specifically, the process of “Doppler-shifted Ponderomotive bunching” is significant to eliminate the very high-energy spread and understand the importance of chirping the laser pulse frequency. We intend to publish the results of the mixing process in 2-D. We intend to publish Chirp-induced transparency. More information can be found in the document.

Authors:
 [1];  [2]
  1. Duke Univ., Durham, NC (United States). Dept. of Electrical and Computer Engineering
  2. Imperial College, London (United Kingdom). Dept. of Physics
Publication Date:
Research Org.:
Duke Univ., Durham, NC (United States)
Sponsoring Org.:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
OSTI Identifier:
1291676
Report Number(s):
DOE-DukeU-SC0010012
DOE Contract Number:
SC0010012
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY

Citation Formats

Katsouleas, Thomas C., and Sahai, Aakash A. DOE-HEP Final Report for 2013-2016: Studies of plasma wakefields for high repetition-rate plasma collider, and Theoretical study of laser-plasma proton and ion acceleration. United States: N. p., 2016. Web. doi:10.2172/1291676.
Katsouleas, Thomas C., & Sahai, Aakash A. DOE-HEP Final Report for 2013-2016: Studies of plasma wakefields for high repetition-rate plasma collider, and Theoretical study of laser-plasma proton and ion acceleration. United States. doi:10.2172/1291676.
Katsouleas, Thomas C., and Sahai, Aakash A. 2016. "DOE-HEP Final Report for 2013-2016: Studies of plasma wakefields for high repetition-rate plasma collider, and Theoretical study of laser-plasma proton and ion acceleration". United States. doi:10.2172/1291676. https://www.osti.gov/servlets/purl/1291676.
@article{osti_1291676,
title = {DOE-HEP Final Report for 2013-2016: Studies of plasma wakefields for high repetition-rate plasma collider, and Theoretical study of laser-plasma proton and ion acceleration},
author = {Katsouleas, Thomas C. and Sahai, Aakash A.},
abstractNote = {There were two goals for this funded project: 1. Studies of plasma wakefields for high repetition-rate plasma collider, and 2. Theoretical study of laser-plasma proton and ion acceleration. For goal 1, an analytical model was developed to determine the ion-motion resulting from the interaction of non-linear “blow-out” wakefields excited by beam-plasma and laser-plasma interactions. This is key to understanding the state of the plasma at timescales of 1 picosecond to a few 10s of picoseconds behind the driver-energy pulse. More information can be found in the document. For goal 2, we analytically and computationally analyzed the longitudinal instabilities of the laser-plasma interactions at the critical layer. Specifically, the process of “Doppler-shifted Ponderomotive bunching” is significant to eliminate the very high-energy spread and understand the importance of chirping the laser pulse frequency. We intend to publish the results of the mixing process in 2-D. We intend to publish Chirp-induced transparency. More information can be found in the document.},
doi = {10.2172/1291676},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2016,
month = 8
}

Technical Report:

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  • Numerical simulation was used to study the advantages of a multicavity linac for improving the quality of the electron beam due to the technique of phase synchronism. This also increases the shunt resistance of the accelerator, which is desirous if very high energy is the goal. However, if a particular energy is required, then the shunt resistance must be held constant. Fortunately, a cavity's quality factor, Q, is approximately inversely proportional ot its length if its aspect ratio is much less than one. Therefore, the shunt resistance can be controlled by varying the length of the cavities.
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