A   B   C   D   E   F   G   H   I   J   K   L   M   N   O   P   Q   R   S   T   U   V   W   X   Y   Z  

Hanayama, R.

Paper Title Page
THPD054 Inverse Compton Scattering by Laser Accelerated Electrons and its Application to Standoff Detection of Hidden Objects 4404
 
  • Y. Kitagawa, K. Fujita, R. Hanayama, K. Ishii, Y. Mori
    GPI, Hamamatsu
  • T. Kawashima
    Hamamatsu Photonics K.K., Hamamatsu
  • H. Kuwabara
    IHI, Yokohama
 
 

A technique for remote detection of hidden objects is an urgent issue, but is not yet realized, because a source and a sensor must be located on the same side of the object. An ultra-intense laser can produce extremely short and directional radiations, that is the inverse Compton scatterings used for the backscattering system. We here demonstrate that the laser-wakefiled-accelerated 10-MeV electrons inversely scatter the same laser light to keV X-ray emissions. A 10 TW OPCPA Ti:sapphire laser BEAT ( 1J output, wavelength 815 nm, and pulse width 150fs) is divided to two beams. A 0. 8-J beam is focused to an entrance edge of helium gasjet to accelerate electrons via wakefield and the other 0.2-J beam is focused to the exit of the plasma channel from the opposite direction. A second harmonic probe light measured the channel density. To the upstream direction of the latter beam, a CdTe detector analyzed the Compton spectrum under a photon counting mode* in the range of 1 keV to 20 keV, which well agrees with that calculated from the obtained electron spectrum up to a few tens MeV. We also have observed that the emission is strong into the laser axis direction.


*H. Kuwabara, Y. Mori, Y. Kitagawa, 'Coincident Measurement of a Weakly Backscattered X-ray with a CPA Laser-Produced X-ray Pulse', Plasma Fusion Research: 3, 003-004 (2008).