Cloud Chamber Photograph Of The First Positron Identified By C.D. Anderson

Those who study the history of science will enjoy any of these educational, scientific gifts featuring the "Cloud Chamber Photograph Of The First Positron Identified By C.D. Anderson". Specifically, a 6 mm lead plate separates the upper half of the chamber from the lower half. The positron must have come from below since the upper track is bent more strongly in the magnetic field indicating a lower energy.