Americium-240 (Am-240)

Identity

Protons

95

Neutrons

145

Mass number

240

Mass

240 ± 15 u

Mass excess

51.510 MeV

Spin

(3-)

Stability

Half-life: 2.12 days

Natural occurrence

Not found in nature

Decays to

• positron emission 100.0 % → Pu-240
• alpha 0.00019 % → Np-236