Decay Simulator: Fermium-243

General data

Radioactive decay series

• Fermium-243 231 ms
• Californium-239 28 s · 90.1%
• Curium-235 300 s · 58.6%
• Einsteinium-243 22 s · 9.9%
• Berkelium-239 unknown · 37.6%
• Americium-235 10.3 min · 58.4%
• Californium-243 10.6 min · 3.9%
• Curium-239 2.5 h · 37.7%
• Plutonium-235 25.3 min · 58.1%
• Berkelium-243 4.6 h · 3.3%
• Americium-239 11.9 h · 37.7%
• Neptunium-235 396.1 d · 58.1%
• Curium-243 29.18 a · 3.3%
• Plutonium-231 8.6 min · 0.59%
• Neptunium-231 48.8 min · 0.76%
• Uranium-231 4.2 d · 0.75%
• Uranium-227 1.1 min · 0.059%
• Thorium-223 0.60 s · 0.059%
• Radium-219 9 ms · 0.059%
• Radon-215 2.3 μs · 0.059%
• Protactinium-227 38.3 min · 0.015%
• Actinium-223 2.12 min · 0.013%
• Francium-219 22 ms · 0.013%
• Plutonium-239 24109 a · 41.1%
• Uranium-235 7.040×10⁸ a · 99.2%
• Thorium-231 25.52 h · 99.2%
• Protactinium-231 32740 a · 99.9%
• Actinium-227 21.773 a · 99.9%
• Thorium-227 18.694 d · 98.5%
• Francium-223 21.99 min · 1.4%
• Radium-223 11.4352 d · 99.9%
• Radon-219 3.96 s · 99.9%
• Polonium-215 1.781 ms · 99.9%
• Lead-211 36.1648 min · 99.9%
• Astatine-215 37 μs · 0.013%
• Bismuth-211 2.14 min · 99.9%
• Polonium-211 0.516 s · 0.33%
• Thallium-207 4.77 min · 99.7%
• Lead-207 stable

Rare branches (below 0.01%)

Rare branches are transformations that occur in fewer than 0.01% of decays, e.g. double beta decay or cluster emission. The nuclides they produce are practically absent from a sample, so they are hidden by default to keep the main path clear. In this series: branches - 6, nuclides - 15.

• Americium-243 7345 a · 0.0096%
• Neptunium-239 2.356 d · 0.0096%
• Astatine-219 56 s · 8.3×10⁻⁵%
• Lead-209 3.235 h · 8.9×10⁻⁸%
• Bismuth-209 2.01×10¹⁹ a · 8.9×10⁻⁸%
• Thallium-205 stable · 8.9×10⁻⁸%
• Lead-215 142 s · 7.9×10⁻¹⁰%
• Bismuth-215 7.6 min · 7.7×10⁻⁵%
• Lead-210 22.20 a · 7.9×10⁻¹⁰%
• Mercury-207 2.9 min · 7.9×10⁻¹⁰%
• Bismuth-210 5.012 d · 7.9×10⁻¹⁰%
• Polonium-210 138.378 d · 7.9×10⁻¹⁰%
• Mercury-206 8.32 min · 1.5×10⁻¹⁷%
• Thallium-206 4.202 min · 1.1×10⁻¹⁵%
• Lead-206 stable · 7.9×10⁻¹⁰%

How to read the simulation

Grid: each pixel is one atom of the starting isotope. When an atom decays, the pixel takes the colour of the decay product - in decay series mode the product can decay further. The moment each atom decays is random, but the probability follows from the half-life, so after one T½ about half of the atoms remain, after two - about a quarter.

Chart N(t): what percentage of the sample atoms each nuclide makes up at a given moment. The line of the starting isotope falls (by half after each T½), the lines of stable products rise, and those of short-lived ones first rise, then fall.

Chart A(t): activity, i.e. the number of decays per second (becquerel, Bq). It depends on the number of atoms and on how fast they decay: for the same number of atoms, the shorter the T½, the higher the activity.

Simulation time runs faster (or slower) than real time - the time scale slider sets the multiplier. This way you can watch the decay of isotopes that live from fractions of a second to billions of years.

Well-known isotopes

• H-3 - Tritium - glowing watch hands, nuclear fusion fuel.
• C-14 - Radiocarbon dating.
• K-40 - Natural radioactivity - in bananas and in our bodies.
• Co-60 - Radiotherapy and radiation sterilization.
• I-131 - Thyroid treatment; Chernobyl fallout.
• Cs-137 - Long-lasting contamination after Chernobyl and Fukushima.
• Rn-222 - Radon in basements and mines.
• Ra-226 - The longest-lived isotope of radium - the element discovered by Marie and Pierre Curie in 1898.
• U-235 - Nuclear power plant fuel; start of the actinium series.
• U-238 - Age of the Earth; start of the uranium series.
• Pu-238 - Power source for space probes (Voyager, Curiosity rover).
• Am-241 - Ionization smoke detectors.