  We report results on superconducting tunneling spectroscopy of a carbon
nanotube quantum dot. Using a three-probe technique that includes a
superconducting tunnel probe, we map out changes in conductance due to band
structure, excited states, and end-to-end bias. The superconducting probe
allows us to observe enhanced spectroscopic features, such as robust signals of
both elastic and inelastic co-tunneling. We also see evidence of inelastic
scattering processes inside the quantum dot.
