DISPERSION OF LATENT IMAGE SPECKS FORMED BY BETA-RADIATION OF SULFUR-SENSITIZED EMULSIONS

Dispersion of latent-image specks formed by beta-radiation was studied for sulfur-sensitized emulsions by means of the arrested development technique. The number of latent-image specks in one grain, n, was coun ted and the distribution of n was measured. The distribution is wider than that for grains exposed to light and split into two peaks at stro nger sensitization levels. One was a broad peak at n greater than or e qual to 1 and the other was a sharp peak at n = 0. The average number of beta-particles that strike one grain, w, was evaluated statisticall y. The average number of latent-image specks in one grain, v, increase d with w. The relationship between w and v was linear at small w. It d eviated upward for strongly sensitized emulsions and downward for weak ly sensitized and unsensitized emulsions. The average number of latent -image specks formed by one strike of a beta-particle, z, was evaluate d and it increased with the sensitization level. This value z is usefu l as a quantitative index of the dispersion of latent-image specks.