Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Cerenkov photon production rate (normalized to activity) as a function of time from a pure sample. (a) and (b) shows two different time periods for 225Ac. Note the x-axis varies in scale to account for the different half-lives of the isotopes and that the y-axis of (c) and (d) has a factor of 10−3.
