Coulomb Sums and Modification of Nucleons in The Atomic Nucleus

Experimental values of Coulomb sums for q > 2 fm^(-1) are considered. Assuming that a part of nucleons is modified in the nucleus, an approach is offered, in the framework of which the calculation is in agreement with the experimental data. It gives the nuclear matter density value, above which the nucleon changes its properties. The radius of a modified proton is estimated, the possibilities for a further investigation into its properties are discussed.