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Title: Measurements of ionization states in warm dense aluminum with betatron radiation

Abstract

Time-resolved measurements of the ionization states of warm dense aluminum via K-shell absorption spectroscopy are demonstrated using betatron radiation generated from laser wakefield acceleration as a probe. The warm dense aluminum is generated by irradiating a free-standing nanofoil with a femtosecond optical laser pulse and was heated to an electron temperature of ~20–25 eV at a close-to-solid mass density. Absorption dips in the transmitted x-ray spectrum due to the Al 4+ and Al 5+ ions are clearly seen during the experiments. The measured absorption spectra are compared to simulations with various ionization potential depression models, including the commonly used Stewart-Pyatt model and an alternative modified Ecker-Kröll model. Furthermore, the observed absorption spectra are in approximate agreement with these models, though indicating a slightly higher state of ionization and closer agreement for simulations with the modified Ecker-Kröll model.

Authors:
 [1];  [1];  [2];  [2];  [3];  [2];  [3];  [2];  [3];  [4];  [3]
  1. Univ. of Alberta, Edmonton, AB (Canada); SLAC National Accelerator Lab., Menlo Park, CA (United States)
  2. Univ. du Quebec, Varennes, QC (Canada)
  3. Univ. of Alberta, Edmonton, AB (Canada)
  4. Univ. of British Columbia, Vancouver, BC (Canada)
Publication Date:
Research Org.:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1368691
Grant/Contract Number:
AC02-76SF00515; 2014-05736
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Physical Review E
Additional Journal Information:
Journal Volume: 95; Journal Issue: 5; Journal ID: ISSN 2470-0045
Publisher:
American Physical Society (APS)
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS

Citation Formats

Mo, M. Z., Chen, Z., Fourmaux, S., Saraf, A., Kerr, S., Otani, K., Masoud, R., Kieffer, J. -C., Tsui, Y., Ng, A., and Fedosejevs, R.. Measurements of ionization states in warm dense aluminum with betatron radiation. United States: N. p., 2017. Web. doi:10.1103/PhysRevE.95.053208.
Mo, M. Z., Chen, Z., Fourmaux, S., Saraf, A., Kerr, S., Otani, K., Masoud, R., Kieffer, J. -C., Tsui, Y., Ng, A., & Fedosejevs, R.. Measurements of ionization states in warm dense aluminum with betatron radiation. United States. doi:10.1103/PhysRevE.95.053208.
Mo, M. Z., Chen, Z., Fourmaux, S., Saraf, A., Kerr, S., Otani, K., Masoud, R., Kieffer, J. -C., Tsui, Y., Ng, A., and Fedosejevs, R.. Fri . "Measurements of ionization states in warm dense aluminum with betatron radiation". United States. doi:10.1103/PhysRevE.95.053208. https://www.osti.gov/servlets/purl/1368691.
@article{osti_1368691,
title = {Measurements of ionization states in warm dense aluminum with betatron radiation},
author = {Mo, M. Z. and Chen, Z. and Fourmaux, S. and Saraf, A. and Kerr, S. and Otani, K. and Masoud, R. and Kieffer, J. -C. and Tsui, Y. and Ng, A. and Fedosejevs, R.},
abstractNote = {Time-resolved measurements of the ionization states of warm dense aluminum via K-shell absorption spectroscopy are demonstrated using betatron radiation generated from laser wakefield acceleration as a probe. The warm dense aluminum is generated by irradiating a free-standing nanofoil with a femtosecond optical laser pulse and was heated to an electron temperature of ~20–25 eV at a close-to-solid mass density. Absorption dips in the transmitted x-ray spectrum due to the Al4+ and Al5+ ions are clearly seen during the experiments. The measured absorption spectra are compared to simulations with various ionization potential depression models, including the commonly used Stewart-Pyatt model and an alternative modified Ecker-Kröll model. Furthermore, the observed absorption spectra are in approximate agreement with these models, though indicating a slightly higher state of ionization and closer agreement for simulations with the modified Ecker-Kröll model.},
doi = {10.1103/PhysRevE.95.053208},
journal = {Physical Review E},
number = 5,
volume = 95,
place = {United States},
year = {Fri May 19 00:00:00 EDT 2017},
month = {Fri May 19 00:00:00 EDT 2017}
}

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