Bounds on heavy axions with an X-ray free electron laser

Jack W. D. Halliday, Giacomo Marocco, Konstantin A. Beyer +18

We present new exclusion bounds obtained at the European X-ray Free Electron Laser facility (EuXFEL) on axion-like particles (ALPs) in the mass range 10^{-3} eV < m_a < 10^4 eV. Ou…