Collisional depopulation of helium rydberg atoms by atoms and molecules

The total depopulation cross sections by ${\mathrm{N}}_{2}$ of high rubidium Rydberg states, $\mathrm{Rb}(\mathrm{ns}) (n=25\ensuremath{-}46)$ and $\mathrm{Rb}(\mathrm{nd}) (n=23\ensuremath{-}44)$, have been measured using time-resolved field ionization technique and compared to previous results obtained on the quenching of $\mathrm{Rb}(\mathrm{nl})$ by CO. It is shown that the $\mathrm{Rb}(\mathrm{nl})$ depopulation by ${\mathrm{N}}_{2}$ is much less efficient than the $\mathrm{Rb}(\mathrm{nl})$ depopulation by CO and leads mainly to the quasielastic process of angular momentum mixing via the short-range interaction between the quasifree Rydberg-state electron and the molecule. It is clearly demonstrated that the presence of a permanent dipole in CO changes the collisional processes drastically. The agreement between experimental and theoretical predictions based on the impulse approximation is quite satisfactory.The total depopulation cross sections by ${\mathrm{N}}_{2}$ of high rubidium Rydberg states, $\mathrm{Rb}(\mathrm{ns}) (n=25\ensuremath{-}46)$ and $\mathrm{Rb}(\mathrm{nd}) (n=23\ensuremath{-}44)$, have been measured using time-resolved field ionization technique and compared to previous results obtained on the quenching of $\mathrm{Rb}(\mathrm{nl})$ by CO. It is shown that the $\mathrm{Rb}(\mathrm{nl})$ depopulation by ${\mathrm{N}}_{2}$ is much less efficient than the $\mathrm{Rb}(\mathrm{nl})$ depopulation by CO and leads mainly to the quasielastic process of angular momentum mixing via the short-range interaction between the quasifree Rydberg-state electron and the molecule. It is clearly demonstrated that the presence of a permanent dipole in CO changes the collisional processes drastically. The agreement between experimental and theoretical predictions based on the impulse approximation is quite satisfactory.

Physical Review AAug 1, 198423 citations

The total depopulation cross sections by

{\mathrm{N}}_{2}

of high rubidium Rydberg states, $\mathrm{Rb}(\mathrm{ns}) (n=25\ensuremath{-}46)$ and $\mathrm{Rb}(\mathrm{nd}) (n=23\ensuremath{-}44)$, have been measured using time-resolved field ionization technique and compared to previous results obtained on the quenching of

\mathrm{Rb}(\mathrm{nl})

by CO. It is shown that the

\mathrm{Rb}(\mathrm{nl})

depopulation by

{\mathrm{N}}_{2}

is much less efficient than the

\mathrm{Rb}(\mathrm{nl})

depopulation by CO and leads mainly to the quasielastic process of angular momentum mixing via the short-range interaction between the quasifree Rydberg-state electron and the molecule. It is clearly demonstrated that the presence of a permanent dipole in CO changes the collisional processes drastically. The agreement between experimental and theoretical predictions based on the impulse approximation is quite satisfactory.