Electron spectroscopy at the high-energy endpoint of electron-nucleus bremsstrahlung

The high-energy endpoint of electron-nucleus bremsstrahlung has been studied in inverse kinematics: For collisions U⁸⁸⁺+N₂ → U⁸⁸⁺+[N₂⁺]^* + e^- + γ the energy distribution of electrons scattered under θ_e^lab = 0 ^circle with v_e ∼ v_proj was measured coincident with the bremsstrahlung photons emitted under various angles θ_γ^lab. The triple-differential cross sections provide a stringent test for the fully relativistic theory of electron-nucleus bremsstrahlung. Furthermore the studied process, also termed radiative electron capture to continuum RECC, was compared to the competing processes of non-radiative electron capture to continuum ECC and the electron loss to continuum ELC.