X-ray induced desorption and photochemistry in CO ice
  We report an investigation of X-ray induced desorption of neutrals, cations
and anions from CO ice. The desorption of neutral CO, by far the most abundant,
is quantified and discussed within the context of its application to
astrochemistry. The desorption of many different cations, including large
cations up to the mass limit of the spectrometer, are observed. In contrast,
the only desorbing anions detected are O$^-$ and C$^-$. The desorption
mechanisms of all these species are discussed with the aid of their
photodesorption spectrum. The evolution of the X-ray absorption spectrum shows
significant chemical modifications of the ice upon irradiation, which along
with the desorption of large cations gives a new insight into X-ray induced
photochemistry in CO ice.
