Laser Photodetachment Spectroscopy of the $S_{2}^{-}$ Ion

We have conducted low-resolution photodetachment spectroscopy of the $S_{2}^{-}$ ion over a broad range of photon energies. The ions are created in an ion trap by a two-step dissociative attachment process. The detachment is achieved with a tunable ring-cavity titanium:sapphire laser. Evaporative cooling is used to remove the most energetic ions. The altered photodetachment spectroscopy is then compared to that of the non-cooled ions as a method of identifying detachment thresholds. Our results exhibit structure that may be due to vibrational energy levels. Future experiments will focus on high-resolution detachment spectroscopy of these and other ions.