Transport of energy by ultraintense laser-generated electrons in nail-wire targets

Journal Article · Sun Nov 15 00:00:00 EST 2009 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.3261810· OSTI ID:21274266

Ma, T ^[1]; Key, M H; Hatchett, S P; Mackinnon, A J; MacPhee, A G; Patel, P K; Wilks, S C ^[2]; Mason, R J ^[3]; Akli, K U; Stephens, R B ^[4]; Daskalova, R L; Freeman, R R; Highbarger, K; Van Woerkom, L D ^[5]; Green, J S; Norreys, P A ^[6]; Jaanimagi, P A; Theobald, W ^[7]; King, J A; Wei, M S ^[1]

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1. Department of Mechanical and Aerospace Engineering, University of California-San Diego, La Jolla, California 92093 (United States)
2. Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)
3. Research Applications Corporation, Los Alamos, New Mexico 87544 (United States)
4. General Atomics, San Diego, California 92186 (United States)
5. College of Mathematical and Physical Sciences, Ohio State University, Columbus, Ohio 43210 (United States)
6. Central Laser Facility, Rutherford Appleton Laboratory, Didcot OX11 OQX (United Kingdom)
7. Laboratory of Laser Energetics, University of Rochester, Rochester, New York 14623 (United States)

Nail-wire targets (20 {mu}m diameter copper wires with 80 {mu}m hemispherical head) were used to investigate energy transport by relativistic fast electrons generated in intense laser-plasma interactions. The targets were irradiated using the 300 J, 1 ps, and 2x10{sup 20} W{center_dot}cm{sup -2} Vulcan laser at the Rutherford Appleton Laboratory. A spherically bent crystal imager, a highly ordered pyrolytic graphite spectrometer, and single photon counting charge-coupled device gave absolute Cu K{alpha} measurements. Results show a concentration of energy deposition in the head and an approximately exponential fall-off along the wire with about 60 {mu}m 1/e decay length due to resistive inhibition. The coupling efficiency to the wire was 3.3{+-}1.7% with an average hot electron temperature of 620{+-}125 keV. Extreme ultraviolet images (68 and 256 eV) indicate additional heating of a thin surface layer of the wire. Modeling using the hybrid E-PLAS code has been compared with the experimental data, showing evidence of resistive heating, magnetic trapping, and surface transport.

• OSTI ID: 21274266
• Journal Information: Physics of Plasmas, Vol. 16, Issue 11; Other Information: DOI: 10.1063/1.3261810; (c) 2009 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
BEAM-PLASMA SYSTEMS
CHARGE-COUPLED DEVICES
ELECTRON TEMPERATURE
ELECTRONS
LASER-RADIATION HEATING
RELATIVISTIC PLASMA