Formation of CO₂, CH₃OH, and CH₃CH₂OH on an icy grain analogue using fast O-atoms

Carbon dioxide (CO₂), methanol (CH₃OH), and ethanol (CH₃CH₂OH) are produced in collisions of a superthermal, 8 eV beam of ground-state O(³P) atoms with CH4/CO ice mixture adsorbed on a gold surface at 4.8K. The reaction-generated products are detected and analyzed using the techniques of temperature programmed desorption (TPD), quadrupole mass spectrometry (QMS). A random-walk procedure is used to identify the unique fractionation patterns of CO₂, CH₃OH, and CH₃CH₂OH from the patterns of other species such as H₂, N₂, O₂, CO, H₂O, CH₄, and H₂CO embedded in the CH₄, blanket and devolved in the TPD/QMS process.