Spectrometers have been Developed which use Deflection
Mu-mesons are elementary particles having mass 207 times and charge equal to that of an electron. When a beam of mu-mesons is incident on nuclei like graphite, mu-mesons move in Bohr orbits which have got radius 207 țimes shorter and energy 207 times greater than that of an electron. When these mu-mesons are excited and de-excited, they emit mesonic X-rays.
The obseryed experimental values of energies of X-rays dépend upon the value of nuclear radius and are usęed to estimate the size of the nucleus. The average value. of nuclear radius found by this method is equal to (1.20 ± 0.03) A x 1015 m.
Electron Scattering Method The most important method of finding thẻ electric charge distribution inside atomic nucleus is based on the elastic scattering of électrons by nuclei as a function of scàttering angle: The charge distribution in the nucleus is obtained from the best fit to the experimental dáta óf electrons scatteréd in the enèrgy| range from 50 MeV to 1 BeV.
It gives the following charge distribution p(r) as a function of distance, 'r, from the nuclear.centre:
and'spectrometers have been developed which use deflection of positively charged ions by the applieation of electric and maghetic fields in evacuated chambers to estimate their nueléar mass. Aston's mass spectrograph and Dempster's mass-speetrometër are two typical- instruments which aré described as follows: may.
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