Doppler-free ion imaging of hydrogen molecules produced in bimolecular reactions

Doppler-free two-color [(1 + 1′) + 1/1′] resonance enhanced multiphoton ionization (REMPI) is used to determine the angular distributions of HD(v′ = 1, j′) products from the reaction of H + D2 at a collision energy of 1.7 eV, allowing us to observe quantum oscillations in good agreement with theory.