Abstract
When charged particles collide with atoms, atomic inner shell electrons become ionized, producing characteristic X-rays. This phenomenon is called particle-induced X-ray emission (PIXE). The characteristic X-ray production cross-sections from PIXE are very large, and the characteristic X-rays of elements contained in a sample are easily measured by a Silicon detector with a high energy resolution. Hence, sodium to uranium can be detected with a sensitivity of ppb~ppm, and PIXE has been applied to trace element analysis. Scanning ion beams can be used to obtain the spatial distributions of elements in a sample. Furthermore, the distributions of elements inside a cell can be investigated using micro ion beams. PIXE analysis is a very useful technique for multi-elemental analysis and is now widely used in many fields and applications, including chemistry, medicine, biology, archaeology, agriculture, materials science, fisheries science, geology, petrology, environmental study, contamination monitoring, resource search, semiconductors, metal, astrophysics, earth science, criminal investigations, and food.
Highlights
When heavy charged particles, on the order MeV, bombard target atoms, characteristic X-rays of the target atoms are produced
Since the continuous background appearing in the X-ray energy spectrum obtained by heavy charged particle bombardment is much smaller than that of the electron bombardment, particle-induced X-ray emission (PIXE) can be used for trace element analysis
The inner shell ionization cross sections σ i can be estimated by using the binary encounter approximation, based on Rutherford scattering between the electron and the projectile, and by using the velocity distribution calculated classically, taking into consideration the inner shell electron being bound by the Coulomb potential of the target nucleus [4]
Summary
On the order MeV, bombard target atoms, characteristic X-rays of the target atoms are produced. The inner shell ionization cross sections σ i can be estimated by using the binary encounter approximation, based on Rutherford scattering between the electron and the projectile, and by using the velocity distribution calculated classically, taking into consideration the inner shell electron being bound by the Coulomb potential of the target nucleus [4] This theory expresses σ i as the function. This theory expresses σi as the function of meE/mpU, U2σi(E, U)/z2 = f (meE/mpU). The inner shell ionization cross sections by heavy charged particles were measured energetically in the 1970s and converted into a table in the 1980s [10]
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call