Abstract
A high peak brilliance, laser-based Compton-scattering $\ensuremath{\gamma}$-ray source, capable of producing quasimonoenergetic photons with energies ranging from 0.1 to 0.9 MeV has been recently developed and used to perform nuclear resonance fluorescence (NRF) experiments. Techniques for characterization of $\ensuremath{\gamma}$-ray beam parameters are presented. The key source parameters are the size ($0.01\text{ }\text{ }{\mathrm{mm}}^{2}$), horizontal and vertical divergence ($6\ifmmode\times\else\texttimes\fi{}10\text{ }\text{ }{\mathrm{mrad}}^{2}$), duration (16 ps), and spectrum and intensity (${10}^{5}\text{ }\text{ }\mathrm{photons}/\mathrm{shot}$). These parameters are summarized by the peak brilliance, $1.5\ifmmode\times\else\texttimes\fi{}{10}^{15}\text{ }\text{ }\mathrm{photons}/{\mathrm{mm}}^{2}/{\mathrm{mrad}}^{2}/\mathrm{s}/0.1%$ bandwidth, measured at 478 keV. Additional measurements of the flux as a function of the timing difference between the drive laser pulse and the relativistic photoelectron bunch, $\ensuremath{\gamma}$-ray beam profile, and background evaluations are presented. These results are systematically compared to theoretical models and computer simulations. NRF measurements performed on $^{7}\mathrm{Li}$ in LiH demonstrate the potential of Compton-scattering photon sources to accurately detect isotopes in situ.
Highlights
Over the past two decades, considerable technological improvements in the field of high intensity lasers, highbrightness electron linacs, and x-ray diagnostics have contributed to the maturation of a novel type of light sources based on Compton scattering, where incident laser photons are scattered by a relativistic electron beam to generate tunable, highly collimated light pulses with picosecond or femtosecond durations, and relatively narrow spectral bandwidth [1]
We present a complete characterization of the source mainly when the electron beam is tuned at 116 MeV and the laser at 532 nm
We have demonstrated and characterized Compton scattering from a novel high-brightness -ray source
Summary
Over the past two decades, considerable technological improvements in the field of high intensity lasers, highbrightness electron linacs, and x-ray diagnostics have contributed to the maturation of a novel type of light sources based on Compton scattering, where incident laser photons are scattered by a relativistic electron beam to generate tunable, highly collimated light pulses with picosecond or femtosecond durations, and relatively narrow spectral bandwidth [1]. At photon energies below 100 keV, advanced biomedical imaging techniques, including ultrafast x-ray protein crystallography [2], phase contrast imaging [3], and K-edge imaging [4], are under consideration by a number of groups worldwide. At -ray photon energies relevant for nuclear processes and applications, these new radiation sources will produce the highest peak brilliance. HI S [10], a large 2–86 MeV highenergy -ray facility producing polarized photons via intracavity Compton backscattering from a free-electron laser, has been used as a research tool to assign the parity of excited states in nuclei [11]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
