NRA - Nuclear reaction analysis
When one would like to analyze light elements with very high sensitivity the NRA method NRA (Nuclear Reaction Analysis) is appropriate. The method is based on detection of nuclear reaction products and measurements of their energy spectra. The cross sections for some nuclear reactions become large (a few barns) if the energy of the projectile (p, D, He,...) is high enough (a few MeV). For certain combinations of projectile and target type the reactions display the resonant behavior at some projectile energies. These allows us to determine depth profiles of the target atoms by changing the projectile energy. Regarding the nature of the nuclear reaction and the following detection there are two approaches possible: either the g - ray spectra (PIGE - Particle Induced Gamma-ray Emission) are measured, or the particles (p, a,...) are detected which appear as products of the nuclear reaction. A few typical nuclear reaction for IBA excitation of light elements are:
At detection of particles:
detection of gamma rays:
rays for depth profiles of hydrogen:
NRA method is used on Microbeam beamline.
Last updated: 11/21/2007