  We realize a device, based on InAs two-dimensional electron gas proximitized
by superconducting Al, which allows a single quantum dot level to be used as a
spectrometer of the density of states in a nanowire. Applying a magnetic field
parallel to the plane of the device causes the levels of the dot to split,
enabling spin resolved spectroscopy. Using this method, we are able to study
the spin and charge polarization of the allowed transport through sub-gap
states which form in the nanowire and evolve with varying magnetic field and
gate voltage.
