A is greater than about 40.
A parameter named for this process equals one-half the Coulomb energy of a sphere over the surface energy of the sphere. The multiplication factor  K  describing this process is given by the product of six other dimensionless factors, including epsilon and eta, which describe the "fast" and "thermal" types of it respectively. The semi-empirical mass formula predicts that this process occurs when  Z -squared over  A is greater than about 40. Heavy (*)  water moderates the products of this process. This process was found to be self-sustaining in a 1942 experiment led by Enrico Fermi under a football field. It produces two new neutrons in addition to two daughter nuclides. For 10 points, name this process in which a nucleus splits in half, which powers nuclear reactors.
A parameter named for this process equals one-half the Coulomb energy of a sphere over the surface energy of the sphere.
nuclear  fission  