PIXE Analysis of Atmospheric Gases

A low-cost device has been constructed and tested which allows the concentration and collection of gases and vapors having boiling points higher than -153°C by a cryogenic technique. Concentration factors of 1320 have been achieved. Collected gases were analyzed by the PIXE method, with sensitivities of 12ppm of the concentrate, corresponding to 10ppb of ambient air, achieved with 300 second irradiation times. These studies suggest that ambient air contains heretofore unsuspected compounds with elements in the Mg-Pb region in concentrations of 10-200ppb.