Cf

Californium

Californium-245, the first isotope of this synthetic element, was produced in 1950 by bombarding curium-242 with alpha particles in a 60-inch cyclotron. Californium-252, an isotope with a half-life of about 2.6 years, produces a staggering 170 million neutrons per minute. This powerful neutron emission has led to various practical applications, including its use in neutron moisture gauges to locate water and oil-bearing layers in oil wells.