Rhodium Mössbauer Effect Generated by Bremsstrahlung Excitation

A method for effectively generating long-lived Mössbauer photons and methods for proving the associated Mössbauer effects are reported. For the first time, we observed resonant propagation and resonant absorption of 40-keV Mössbauer photons emitted from ¹⁰³Rh through (γ,γ’) process excited by bremsstrahlung. This is a new efficient way to generate long-lived isomer (>1ms) for Mössbauer spectroscopy with sufficient brilliance. An abnormally large ratio of resonant absorption between horizontal and vertical directions indicates horizontal trapping of Mössbauer photons and anisotropic Mössbauer emission, which can be attributed to gravitational effect on the ¹⁰³Rh Mössbauer isomer with extremely narrow 10^-19eV linewidth.