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Radionuclide Dosimetric Data Sheets

Astatine-218

Isotope:  At-218
Atomic number (Z):  85
Mass number (A):  218
Neutron number (N):  133

Decay modes:  α, β-
Half-life:  1.5 [s]
Decay constant:  4.6210e-01 [1/s]
Daughters:  Bi-214 (99.9%), Rn-218 (0.1%)
Radioactive daughters:  Bi-214, Rn-218

Mean alpha energy:  6.8041 [MeV]
Mean electron energy:  0.00109 [MeV]
Mean photon energy:  0.0 [MeV]
Air kerma rate constant, Γ₁₀:  0.000e+00 [Gy·m²/Bq·s]
Air kerma coefficient, K_air:  0.000e+00 [Gy·m²/Bq·s]
Equilibrium dose constant for weakly-penetrating radiations (α and/or electrons), Δ_wp:  1.090e-12 [Gy·kg/Bq·s]
Equilibrium dose constant for alphas, Δ_α:  1.090e-12 [Gy·kg/Bq·s]
Equilibrium dose constant for betas/electrons, Δ_β-,β+,e-:  1.746e-16 [Gy·kg/Bq·s]
Equilibrium dose constant for photons, Δ_p:  0.000e+00 [Gy·kg/Bq·s]

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/At-218 Summary Spectrum.csv

Spectra source:  ICRP Publication 107: Nuclear Decay Data for Dosimetric Calculations. Ann. ICRP 2008, 38 (3).

Download tabulated beta spectra file here:  www.mirdsoft.org/products/MIRDspecs/At-218 Beta Spectrum.csv

 

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/At-218 Summary Spectrum.csv

 

Energy [MeV]	Yield [#/nt] if > 0.01	Radiation type
6.64668e+00	6.394e-02	Alpha
6.68624e+00	8.991e-01	Alpha
6.74779e+00	3.596e-02	Alpha
1.24318e-01	6.394e-02	Alpha recoil
1.25058e-01	8.991e-01	Alpha recoil
1.26209e-01	3.596e-02	Alpha recoil

 

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

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

 

 

 

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