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Americium-241 (241 Am, Am-241) is an isotope of americium. Like all isotopes of americium, it is radioactive , with a half-life of 432.2 years . 241 Am is the most common isotope of americium as well as the most prevalent isotope of americium in nuclear waste .
243 Am also presents a risk of external irradiation associated with the gamma ray emitted by its short-lived decay product 239 Np. The external irradiation risk for the other two americium isotopes (241 Am and 242m Am) is less than 10% of that for americium-243. [8]
A decay chain that has reached this state, which may require billions of years, is said to be in equilibrium. ... 241 Am: 241 Am α 432.7 a 5.638 237 Np: 237 Np α
Initial experiments yielded four americium isotopes: 241 Am, 242 Am, 239 Am and 238 Am. Americium-241 was directly obtained from plutonium upon absorption of two neutrons. It decays by emission of a α-particle to 237 Np; the half-life of this decay was first determined as 510 ± 20 years but then corrected to 432.2 years.
The decay scheme of a radioactive substance is a graphical presentation of all the transitions occurring in a decay, and of their relationships. Examples are shown below. It is useful to think of the decay scheme as placed in a coordinate system, where the vertical axis is energy, increasing from bottom to top, and the horizontal axis is the proton number, increasing from left to right.
In a thermal reactor, 241 Am captures a neutron to become americium-242, which quickly becomes curium-242 (or, 17.3% of the time, 242 Pu) via beta decay. Both 242 Cm and 242 Pu are much less likely to absorb a neutron, and even less likely to fission; however, 242 Cm is short-lived (half-life 160 days) and almost always undergoes alpha decay to ...
Alpha decay or α-decay is a type of radioactive decay in which an atomic nucleus emits an alpha particle (helium nucleus) ... Americium-241, an alpha emitter, ...
It has a half-life of 30 years, and decays by beta decay without gamma ray emission to a metastable state of barium-137 (137m Ba). Barium-137m has a half-life of a 2.6 minutes and is responsible for all of the gamma ray emission in this decay sequence. The ground state of barium-137 is stable. The photon energy (energy of a single gamma ray) of ...