Knowledge Bank

In an earlier $study1$ we observed the $3p2E\prime (v1=0,v2=1)$ and $3p2E\prime (v1=1,v2=1)$ states of $H3$ in vibronically-allowed excitation from the metastable $N=OB¯2p2A2$ state. In the present work we use these 3p states as intermediate levels in two-color excitation of autoionizing vibrationally-excited Rydberg series. Rydberg states with principal quantum numbers from $n=6$ to $n=50$ are observed. The strongest transitions correspond to nd Rydberg series converging to the $N+=1$ and $N+=2$ states, with $G=0$, of vibrationally excited $H3+$. Weaker transitions are observed to nd Rydberg states converging to $N+=3$ and $N+=4$ levels, also with $G=0$. There is also evidence for excitation of np (or nf) Rydberg states built upon $G=3$, $N+=2$ and $N+=3$ cores. An MQDT analysis is currently in progress.