PIXE Detection Limits for Heavy Ion Projectiles

PIXE minimum detection limits, MDLs, were estimated using C2+, O2+, N2(+), Ne3+, Ar-6 , Kr13+, Xe20+ ion beams with an energy of 1 MeV/amu and C2+, O3+, N3+, Ne4+, Ar7+, Kr14+, Xe22+ beams with an energy of 1.6 MeV/amu as projectiles for the K-lines of the chemical elements T, Cr, Cu, Zn, Zr, Nb, Mo, Ag, Cd, In,Sn, Sb, and L-lines of Zn, Zr, Nb, Mo, Ag. Cd, In, Sn, Sb, Ta, W, Pb, Bi. Background spectra were obtained using 12 mu m PET Hostaphan film as a backing. The results obtained for the different ion beams with the same velocities were compared. It was found that for the chemical elements with Z < 30 the 1.6 MeV/amu neon beam provides the best sensitivity. For the chemical elements with Z >= 30, energy of 1.6 MeV/amu is also preferred. However, in this case, for the chemical elements with 30 <= Z <= 51 the oxygen beam is optimal, and for Z > 51 the neon beam is preferred. The obtained results can be used to develop the quantitative analysis of the elemental composition of aerosols using PET film as a filter backing. They allow optimizing the choice of the projectile specie and energy to obtain the best detection limits of the PIXE analysis.