Cf-252 FTC-CFZ-431
Overview
An official document for the CF-252 source with serial number FTC-CFZ-431 provides a value for the neutron rate and CF-252 mass as of 03/19/1993. The initial neutron rate and mass of cf-252 are stated to be [math]\displaystyle{ 10^{7}s^{-1} }[/math] and 4.2[math]\displaystyle{ \mu g }[/math], respectively.
4.2 [math]\displaystyle{ \mu g }[/math] would generate [math]\displaystyle{ 9.67 \times 10^{6} }[/math] neutrons per second. The desrepency between these two numbers