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Radionuclide Dosimetric Data Sheets
Polonium-204
Summary data
General
Classification
Isotope: Po-204
Atomic number (Z): 84
Mass number (A): 204
Neutron number (N): 120
Radioactive decay
Decay modes: α, Electron capture
Half-life: 3.53 [h]
Decay constant: 5.4544e-05 [1/s]
Daughters: Bi-204 (99.3%), Pb-200 (0.66%)
Radioactive daughters: Bi-204, Pb-200
Dosimetric constants
Mean alpha energy: 0.0362 [MeV]
Mean electron energy: 0.18386 [MeV]
Mean photon energy: 1.16498 [MeV]
Air kerma rate constant, Γ10: 7.532e-17 [Gy·m2/Bq·s]
Air kerma coefficient, Kair: 7.532e-17 [Gy·m2/Bq·s]
Equilibrium dose constant for weakly-penetrating radiations (α and/or
electrons), Δwp: 3.526e-14 [Gy·kg/Bq·s]
Equilibrium dose constant for alphas, Δα: 5.800e-15
[Gy·kg/Bq·s]
Equilibrium dose constant for betas/electrons, Δβ-,β+,e-:
2.946e-14 [Gy·kg/Bq·s]
Equilibrium dose constant for photons, Δp: 1.867e-13
[Gy·kg/Bq·s]
Dose point kernels (plot)
Dose point kernel source: Graves, et al. Medical Physics. 2019 Nov.; 46(11):5284-5293.
Note: Bins are spaced every 0.1 mm until a radius of 10 cm, and every 1 mm until a radius of 2 m.
Download tabulated dose point kernel file here: www.mirdsoft.org/products/MIRDspecs/Po-204 DPK.csv
Summary spectra (plot)
Spectra source: ICRP Publication 107: Nuclear Decay Data for Dosimetric Calculations. Ann. ICRP 2008, 38 (3).
Download tabulated summary spectra file here: www.mirdsoft.org/products/MIRDspecs/Po-204 Summary Spectrum.csv
Tabulated data
Summary spectra (table)
Spectra source: ICRP Publication 107: Nuclear Decay Data for Dosimetric Calculations. Ann. ICRP 2008, 38 (3).
Note: Radiations with yield < 0.01 are excluded from the table, but are available in the linked *.csv data.
Download tabulated summary spectra file here: www.mirdsoft.org/products/MIRDspecs/Po-204 Summary Spectrum.csv
|
Energy [MeV] |
Yield [#/nt] if > 0.01 |
Radiation type |
|
3.24675e-05 |
5.825e+01 |
X-ray |
|
2.48302e-03 |
2.028e-01 |
X-ray |
|
9.45110e-03 |
2.317e-02 |
X-ray |
|
1.07270e-02 |
4.052e-02 |
X-ray |
|
1.08390e-02 |
3.568e-01 |
X-ray |
|
1.26833e-02 |
3.015e-02 |
X-ray |
|
1.29844e-02 |
6.928e-02 |
X-ray |
|
1.30700e-02 |
1.890e-01 |
X-ray |
|
1.32091e-02 |
3.228e-02 |
X-ray |
|
1.53031e-02 |
3.903e-02 |
X-ray |
|
6.31850e-02 |
1.076e-01 |
Gamma |
|
7.50642e-02 |
4.223e-01 |
X-ray |
|
7.74071e-02 |
7.062e-01 |
X-ray |
|
8.71393e-02 |
7.897e-02 |
X-ray |
|
8.76651e-02 |
1.531e-01 |
X-ray |
|
9.00323e-02 |
1.894e-02 |
X-ray |
|
9.01629e-02 |
3.730e-02 |
X-ray |
|
1.22582e-01 |
1.136e-02 |
Gamma |
|
1.37023e-01 |
9.718e-02 |
Gamma |
|
2.03561e-01 |
2.811e-02 |
Gamma |
|
2.44724e-01 |
1.815e-02 |
Gamma |
|
2.70068e-01 |
2.781e-01 |
Gamma |
|
3.04964e-01 |
3.259e-02 |
Gamma |
|
3.17016e-01 |
4.276e-02 |
Gamma |
|
3.62140e-01 |
1.268e-02 |
Gamma |
|
4.26820e-01 |
1.884e-02 |
Gamma |
|
4.51846e-01 |
1.914e-02 |
Gamma |
|
5.34920e-01 |
1.325e-01 |
Gamma |
|
5.39500e-01 |
1.346e-02 |
Gamma |
|
6.80390e-01 |
7.625e-02 |
Gamma |
|
7.51590e-01 |
1.059e-02 |
Gamma |
|
7.62520e-01 |
1.151e-01 |
Gamma |
|
8.83960e-01 |
2.990e-01 |
Gamma |
|
9.05150e-01 |
1.238e-02 |
Gamma |
|
1.01629e+00 |
2.407e-01 |
Gamma |
|
1.04001e+00 |
9.598e-02 |
Gamma |
|
4.07057e-05 |
1.403e+01 |
Auger electron |
|
9.33564e-05 |
1.819e+01 |
Auger electron |
|
1.19539e-04 |
2.997e-02 |
Auger electron |
|
1.76378e-04 |
9.936e+00 |
Auger electron |
|
4.63189e-04 |
3.734e+00 |
Auger electron |
|
9.12429e-04 |
7.218e-01 |
Auger electron |
|
1.53310e-03 |
2.327e-01 |
Conversion electron |
|
1.99116e-03 |
4.609e+00 |
Auger electron |
|
2.29403e-03 |
6.235e-01 |
Auger electron |
|
2.38310e-03 |
7.490e-01 |
Conversion electron |
|
2.72727e-03 |
3.288e-02 |
Auger electron |
|
4.70000e-03 |
7.526e-02 |
Conversion electron |
|
5.55000e-03 |
2.433e-01 |
Conversion electron |
|
6.35310e-03 |
7.471e-01 |
Conversion electron |
|
8.26996e-03 |
8.664e-01 |
Auger electron |
|
9.52000e-03 |
2.437e-01 |
Conversion electron |
|
1.07378e-02 |
3.897e-01 |
Auger electron |
|
1.32388e-02 |
4.191e-02 |
Auger electron |
|
1.72230e-02 |
2.487e-02 |
Conversion electron |
|
2.52250e-02 |
2.582e-02 |
Conversion electron |
|
3.17500e-02 |
5.587e-02 |
Conversion electron |
|
4.03920e-02 |
3.631e-02 |
Conversion electron |
|
4.61910e-02 |
3.472e-01 |
Conversion electron |
|
4.68090e-02 |
5.711e-01 |
Conversion electron |
|
4.74170e-02 |
5.672e-02 |
Conversion electron |
|
6.00181e-02 |
1.495e-01 |
Conversion electron |
|
6.03003e-02 |
3.500e-02 |
Auger electron |
|
6.31850e-02 |
4.880e-02 |
Conversion electron |
|
7.26460e-02 |
1.923e-02 |
Auger electron |
|
1.12729e-01 |
1.274e-02 |
Conversion electron |
|
1.20647e-01 |
5.475e-02 |
Conversion electron |
|
1.33856e-01 |
1.435e-02 |
Conversion electron |
|
1.79236e-01 |
1.488e-01 |
Conversion electron |
|
2.14132e-01 |
1.252e-02 |
Conversion electron |
|
2.26184e-01 |
1.478e-02 |
Conversion electron |
|
2.53692e-01 |
2.325e-02 |
Conversion electron |
|
4.44088e-01 |
1.129e-02 |
Conversion electron |
Useful Links
Isotope decay characteristics are periodically updated as better measurements can be made - changes that may not be reflected on this page. Please see useful links:
National Nuclear Data Center (NNDC): https://www.nndc.bnl.gov/nudat3/mird/
International Atomic Energy Agency (IAEA) Livechart: https://www-nds.iaea.org/relnsd/vcharthtml/VChartHTML.html
Reference Links
ICRP Report 107: https://www.icrp.org/publication.asp?id=ICRP%20Publication%20107
Graves et al. Dose Point Kernels: https://doi.org/10.1002/mp.13789
MIRD Decay Schemes 2nd Edition: https://sites.snmmi.org/SNMMI-MAIN/iCore/Store/StoreLayouts/Item_Detail.aspx?iProductCode=0-932004-80-6
MIRDsoft MIRDspecs version 20250101 (www.mirdsoft.org)
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