Decay Simulator: Astatine-191
General data
| Element name | Astatine |
|---|---|
| Chemical symbol | At |
| Atomic number Z | 85 |
| Isotope name (symbol) | Astatine-191 (At-191) |
| Neutron number N | 106 |
| Mass number A=Z+N | 191 |
Interactive radioactive decay simulation of Astatine-191: atom-by-atom decay, full decay chain, charts of nuclei count and activity.
| Half-life | 1.7 ms |
|---|
Radioactive decay series
- Astatine-191 1.7 ms
- Bismuth-187 37 ms
- Thallium-183 6.9 s
- Mercury-183 8.9 s
- Gold-183 42.8 s · 76.4%
- Platinum-183 6.5 min · 76.0%
- Iridium-183 58 min · 76.0%
- Osmium-183 13.0 h · 76.0%
- Rhenium-183 70.0 d · 76.0%
- Tungsten-183 stable · 76.0%
- Platinum-179 21.2 s · 23.6%
- Iridium-179 79 s · 24.0%
- Osmium-179 6.3 min · 24.0%
- Rhenium-179 19.5 min · 24.0%
- Tungsten-179 37.05 min · 24.0%
- Tantalum-179 1.82 a · 24.0%
- Hafnium-179 stable · 24.0%
- Osmium-175 1.4 min · 0.057%
- Rhenium-175 5.89 min · 0.057%
- Tungsten-175 35.2 min · 0.057%
- Tantalum-175 10.5 h · 0.057%
- Hafnium-175 70.67 d · 0.057%
- Lutetium-175 stable · 0.057%
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 - 1, nuclides - 10.
- Platinum-182 2.7 min · 2.6×10⁻⁴%
- Iridium-182 15 min · 2.6×10⁻⁴%
- Osmium-182 22.04 h · 2.6×10⁻⁴%
- Rhenium-182 64.2 h · 2.6×10⁻⁴%
- Tungsten-182 stable · 2.6×10⁻⁴%
- Osmium-178 5.0 min · 9.9×10⁻⁸%
- Rhenium-178 13.2 min · 9.9×10⁻⁸%
- Tungsten-178 21.6 d · 9.9×10⁻⁸%
- Tantalum-178 2.41 h · 9.9×10⁻⁸%
- Hafnium-178 stable · 9.9×10⁻⁸%
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.
Data sources
- NNDC Wallet Cards 2023 - Data as of 15 October 2024 - licence: Public domain