Neutron production from ultrashort pulse lasers using linear and circular polarization

Journal Article · Fri Jul 15 00:00:00 EDT 2011 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.3615033· OSTI ID:22046902

Davis, J; Petrov, G M ^[1]

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1. Naval Research Laboratory, Plasma Physics Division, 4555 Overlook Ave. SW, Washington, DC 20375 (United States)

An implicit 2D3V particle-in-cell code is used to study proton and deuteron acceleration from an ultrathin CD foil with thickness between 20 and 200 nm using linear and circular polarization. The proton and deuteron beams drive nuclear fusion reactions from converter foils in a pitcher-catcher set-up. The neutron yield for three representative reactions d - d, d - Li, and p - Li has been calculated analytically using the total neutron production cross section and ion stopping power. For linear polarization, maximum normalized neutron yield of Y{sub d-d}=3.4x10{sup 6}, Y{sub d-Li}=3.2x10{sup 7}, and Y{sub p-Li}=6.8x10{sup 6} neutrons/J laser energy has been calculated at the optimum foil thickness of 50 nm. For circular polarization, the optimum foil thickness is 20 nm, for which the corresponding neutron yields are Y{sub d-d}=1.9x10{sup 6}, Y{sub d-Li}=2.0x10{sup 7}, and Y{sub p-Li}=2.7x10{sup 6}, respectively. The laser polarization strongly affects the neutron production; for our regime, i.e., intensity I=1x10{sup 21} W/cm{sup 2}, pulse duration {tau}{sub FWHM}=30 fs, and laser energy {epsilon}{sub laser}=3.8 J, both the conversion efficiency of laser energy into ion kinetic energy and neutron yield are higher for linear polarization. Only for ultrathin ({approx}20 nm) foils in the radiation pressure acceleration regime, circular and linear polarizations yield comparable results.

• OSTI ID: 22046902
• Journal Information: Physics of Plasmas, Vol. 18, Issue 7; Other Information: (c) 2011 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
ACCELERATION
ACCELERATORS
COMPUTERIZED SIMULATION
CROSS SECTIONS
DEUTERON BEAMS
DEUTERONS
FOILS
LASER-PRODUCED PLASMA
LASERS
NEUTRONS
NUCLEAR REACTION YIELD
PLASMA PRODUCTION
PLASMA SIMULATION
POLARIZATION
PROTONS
RADIATION PRESSURE
STOPPING POWER
THERMONUCLEAR REACTIONS