Microwave spectroscopy of Ag I atoms in Rydberg states: S, P and D terms

Microwave resonance transitions of Ag I atoms laser excited to Rydberg S, P and D states of the configuration 4d10nl, for n = 28–39, were measured with MHz accuracy at frequencies from 76 to 363 GHz. Quantum defects and Rydberg–Ritz coefficients were determined based on 47 new resonances, together with doublet fine-structure splittings of P and D terms. An efficient single-laser two-photon excitation path 52S1/2 → 282D5/2 was discovered based on a coincidence with twice the term difference of the transition 52S1/2 → 52P3/2.