Plasma Guided Compton Source*

Compton scattering of laser-accelerated MeV electrons with a counter propagating relativistic laser pulse is a straightforward way to generate multi-keV photon beam in a compact manner. The main challenge is in forming adequate overlap between the beams, with a typical tolerance of a few microns, dictated by the diffraction limit of the laser’s focus.

We will report on a numerical investigation of a compact multi-keV photon source, based on the irradiation of a near-critical plasma plume target by two counter propagating relativistic laser pulses. Under optimal target conditions, these two pulses form positive ion channels in which ionized electrons undergo efficient Direct Laser Acceleration (DLA).

For lasers pulses with normalized intensity of  a₀=3.7, our 3D PIC simulations result in a broad spectral emission of x-ray photons that peaking at  5 keV, emitted with a femtosecond pulse duration, small source size and high Brightness.

Compared to the interaction in vacuum, the guiding of the laser fields and the electron beams in the DLA channel, result in high resilience to micron-scale mismatch in the beams pointing.

We will present these results, report on the progress of realizing this photon source experimentally, and discuss possible applications.