Proton recoil method

The main scattering reaction used is neutron-proton collision, called the proton-recoil method. The knocked-out proton is the particle recorded. 

With the exception of the proton-recoil method, which functions for fast neutrons only ( > 1.0 keV), all the other interactions can be used with neutrons of any energy. However, at every neutron energy, one method may be better than another. The best method will be selected based on the neutron... 

Calculate the measured neutron spectrum obtained by the proton recoil method if the detector response is a 6-function and the source spectrum is the square function shown in the figure below. Assume cr(n, p) is constant for the range , < < 2. 

The nuclear reaction methods are suitable for the determination of several isotopes from to S. The most frequently used reactions are (p, ), (d,p) and (d,a) providing useful alternative methods for the determination of isotopes such as D, and compared with RBS or elastic recoil detection analysis (ERDA). Alpha induced reactions have a limited use. Some Li induced reactions have been tested and the ( B, a) reaction has been used for hydrogen determination and profiling. Cross-sections of 10 to 100 mb sr are observed for proton and deu-teron induced reactions with light isotopes such as D, li. Be and B. Detection limits of the order of 10 jjg g or even less are then possible with measuring times of the order of tens of minutes. Isotopes up to S can be determined in heavier matrices at mg g levels depending on the maximum beam current that the sample can withstand. 

The angular correlation between the internal pairs from the [p a 71) resonance at 840 keV was observed by Devons etal, [ 5], and the half-life of the pair emitting level established as (5.0 0.5) X 10 sec by the recoil distance method (Sect. 24). It is clear that the fluorine reactions have provided an unusually extensive amount of information on the properties of the levels involved, but some difficulties remain. Notable among these is the small proton width and consequent low intensity of capture radiation at the 33O and 935 keV levels of Ne o which seem to have the same properties and to show the same (a y) correlations as the 669 keV resonance which gives capture radiation. 

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