Knowledge Bank

The $N2+$ first negative system $(B2\Sigma u+-X2\Sigma g+)$ has been recorded by laser induced fluorescences of $N2+$ ions confined in an rf trap. The ions were produced by electron impact and had an initial rotational distribution close to the room temperature distribution of the target $N2$ gas. By admitting Ar gas at pressures 10 to 100 times in excess of the $N2$ pressure, variable numbers of $N2+-Ar$ collisions were allowed to occur before the $N2+$ distribution was interrogated by the laser. Since the $N2+$ was translationally energetic, being driven by the trap fields, a rapid and extensive T to R energy transfer was observed. In this way, high rotational states of $N2+$ were populated and the radiative lifetimes of these states were measured. Cross sections for the reaction of specific vibrational states of $N2+$ with Ar and $H2(D2)$ have been measured.