Shape Resonances in H2 as Photolysis Reaction Intermediates
Abstract
Shape resonances in H2 , produced as reaction intermediates in the photolysis of H2S precursor molecules, are measured in a half-collision approach. Before disintegrating into two ground state H atoms, the reaction is quenched by two-photon Doppler-free excitation to the F electronically excited state of H2 . For J =13 , 15, 17, 19, and 21, resonances with lifetimes in the range of nano- to milliseconds were observed with an accuracy of 30 MHz (1.4 mK). The experimental resonance positions are found to be in excellent agreement with theoretical predictions when nonadiabatic and quantum electrodynamical corrections are included. This is the first time such effects are observed in collisions between neutral atoms. From the potential energy curve of the H2 molecule, now tested at high accuracy over a wide range of internuclear separations, the s -wave scattering length for singlet H (1 s )+H (1 s ) scattering is determined at a =0.27353139 a0 .
- Publication:
-
Physical Review Letters
- Pub Date:
- October 2021
- DOI:
- 10.1103/PhysRevLett.127.183001
- arXiv:
- arXiv:2109.13299
- Bibcode:
- 2021PhRvL.127r3001L
- Keywords:
-
- Physics - Atomic Physics
- E-Print:
- 5 Pages, 4 Figures, Accepted by Phys. Rev. Lett