Angular dependence of betatron x-ray spectra from a laser-wakefield accelerator.
We present the first measurements of the angular dependence of the betatron x-ray spectrum produced by electrons inside the cavity of a laser-wakefield accelerator. Electrons accelerated up to 300 MeV energies produce a beam of broadband, forward-directed betatron x-ray radiation extending up to 80 keV. The angular resolved spectrum from an image plate-based spectrometer with differential filtering provides data in a single laser shot. The simultaneous spectral and spatial x-ray analysis allows for a three-dimensional reconstruction of electron trajectories with micrometer resolution, and we find that the angular dependence of the x-ray spectrum is showing strong evidence of anisotropic electron trajectories.
Lawrence Livermore National Laboratory, NIF and Photon Sciences, 7000 East Avenue, Livermore California 94550, USA.
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F
Albert
Lawrence Livermore National Laboratory, NIF and Photon Sciences, 7000 East Avenue, Livermore California 94550, USA.
B B
BB
Pollock
Department of Electrical Engineering, University of California, Los Angeles California 90095, USA.
J L
JL
Shaw
Department of Electrical Engineering, University of California, Los Angeles California 90095, USA.
K A
KA
Marsh
Lawrence Livermore National Laboratory, NIF and Photon Sciences, 7000 East Avenue, Livermore California 94550, USA.
J E
JE
Ralph
Lawrence Livermore National Laboratory, NIF and Photon Sciences, 7000 East Avenue, Livermore California 94550, USA.
Y-H
YH
Chen
Lawrence Livermore National Laboratory, NIF and Photon Sciences, 7000 East Avenue, Livermore California 94550, USA.
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D
Alessi
Lawrence Livermore National Laboratory, NIF and Photon Sciences, 7000 East Avenue, Livermore California 94550, USA.
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A
Pak
Department of Electrical Engineering, University of California, Los Angeles California 90095, USA.
C E
CE
Clayton
SLAC National Accelerator Laboratory, Stanford California 94309, USA.
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SH
Glenzer
Department of Electrical Engineering, University of California, Los Angeles California 90095, USA.
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Joshi