Generation of highly vibrationally excited H2 and detection by 2+1 resonantly enhanced multiphoton ionization

We report the first detection by optical means of highly vibrationally excited H2 X1Σ+g(vx=6–11). Vibrationally excited H2 was generated using a recently discovered hot‐wire effect in H2 gas, and was detected in 40 bands with 2+1 resonantly enhanced multiphoton ionization via the EF state (vEF=0–14). Rotational temperatures are in the range 200–650 K, well below that required for thermal excitation of the observed vibrational levels.