Decay Simulator: Mendelevium-244

General data

Radioactive decay series

• Mendelevium-244 0.39 s
• Einsteinium-240 6.7 s · 87.7%
• Berkelium-236 22 s · 73.1%
• Americium-232 1.31 min · 12.9%
• Fermium-244 3.12 ms · 12.3%
• Californium-240 41.2 s · 18.7%
• Curium-236 6.8 min · 78.9%
• Americium-236 3.6 min · 64.7%
• Plutonium-232 33.1 min · 27.1%
• Neptunium-232 14.7 min · 24.2%
• Einsteinium-244 37 s · 8.2%
• Californium-244 19.4 min · 7.9%
• Uranium-228 9.1 min · 3.0%
• Thorium-224 1.04 s · 2.8%
• Berkelium-244 5.02 h · 2.0%
• Curium-244 18.11 a · 2.0%
• Berkelium-240 4.8 min · 0.33%
• Curium-240 30 d · 6.2%
• Protactinium-228 19.8 h · 0.15%
• Americium-240 50.9 h · 0.031%
• Plutonium-240 6562 a · 2.0%
• Radium-220 18 ms · 2.8%
• Radon-216 29 μs · 2.8%
• Plutonium-236 2.858 a · 70.9%
• Uranium-236 2.343×10⁷ a · 2.0%
• Thorium-232 1.407×10¹⁰ a · 2.0%
• Radium-228 5.75 a · 2.0%
• Actinium-228 6.15 h · 2.0%
• Uranium-232 68.9 a · 95.0%
• Thorium-228 1.9116 a · 97.2%
• Radium-224 3.6313 d · 97.2%
• Radon-220 55.6 s · 97.2%
• Polonium-216 144.0 ms · 97.2%
• Lead-212 10.628 h · 97.2%
• Bismuth-212 60.55 min · 97.2%
• Polonium-212 295.0 ns · 65.1%
• Thallium-208 3.053 min · 34.9%
• Lead-208 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 - 3, nuclides - 11.

• Actinium-224 2.78 h · 0.0028%
• Francium-220 27.4 s · 2.5×10⁻⁴%
• Astatine-216 0.30 ms · 2.5×10⁻⁴%
• Neptunium-236 1.550×10⁵ a · 5.9×10⁻⁸%
• Protactinium-232 1.31 d · 9.5×10⁻¹¹%
• Lead-210 22.20 a · 3.9×10⁻⁹%
• Bismuth-210 5.012 d · 3.9×10⁻⁹%
• Polonium-210 138.378 d · 3.9×10⁻⁹%
• Mercury-206 8.32 min · 7.4×10⁻¹⁷%
• Thallium-206 4.202 min · 5.2×10⁻¹⁵%
• Lead-206 stable · 3.9×10⁻⁹%

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.