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Radionuclide Dosimetric Data Sheets

Protactinium-229

Isotope:  Pa-229
Atomic number (Z):  91
Mass number (A):  229
Neutron number (N):  138

Decay modes:  α, Electron capture
Half-life:  1.5 [d]
Decay constant:  5.3484e-06 [1/s]
Daughters:  Th-229 (99.5%), Ac-225 (0.48%)
Radioactive daughters:  Th-229, Ac-225

Mean alpha energy:  0.0273 [MeV]
Mean electron energy:  0.01313 [MeV]
Mean photon energy:  0.06656 [MeV]
Air kerma rate constant, Γ₁₀:  1.283e-17 [Gy·m²/Bq·s]
Air kerma coefficient, K_air:  1.283e-17 [Gy·m²/Bq·s]
Equilibrium dose constant for weakly-penetrating radiations (α and/or electrons), Δ_wp:  6.478e-15 [Gy·kg/Bq·s]
Equilibrium dose constant for alphas, Δ_α:  4.374e-15 [Gy·kg/Bq·s]
Equilibrium dose constant for betas/electrons, Δ_β-,β+,e-:  2.104e-15 [Gy·kg/Bq·s]
Equilibrium dose constant for photons, Δ_p:  1.066e-14 [Gy·kg/Bq·s]

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/Pa-229 DPK.csv

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/Pa-229 Summary 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/Pa-229 Summary Spectrum.csv

 

Energy [MeV]	Yield [#/nt] if > 0.01	Radiation type
7.95582e-05	6.587e-02	X-ray
8.22366e-05	1.249e+01	X-ray
3.06131e-03	6.895e-02	X-ray
1.11571e-02	1.089e-02	X-ray
1.28126e-02	1.814e-02	X-ray
1.29764e-02	1.595e-01	X-ray
1.56384e-02	3.294e-02	X-ray
1.56464e-02	1.303e-02	X-ray
1.62776e-02	9.369e-02	X-ray
1.64418e-02	1.194e-02	X-ray
1.90652e-02	2.082e-02	X-ray
9.03299e-02	1.825e-01	X-ray
9.37949e-02	2.950e-01	X-ray
1.05278e-01	3.382e-02	X-ray
1.06073e-01	6.595e-02	X-ray
1.09154e-01	1.686e-02	X-ray
3.10893e-05	1.499e-02	Auger electron
5.13264e-05	3.012e+00	Auger electron
1.24913e-04	1.784e-02	Auger electron
1.32763e-04	3.325e+00	Auger electron
1.50422e-04	1.914e-02	Auger electron
1.88215e-04	1.880e+00	Auger electron
5.01366e-04	5.028e-01	Auger electron
1.40904e-03	2.303e-01	Auger electron
2.31341e-03	1.085e+00	Auger electron
2.72689e-03	1.860e-01	Auger electron
3.30502e-03	1.079e-02	Auger electron
9.72826e-03	2.780e-01	Auger electron
1.28545e-02	1.383e-01	Auger electron
1.60156e-02	1.623e-02	Auger electron
2.19620e-02	1.345e-02	Conversion electron
2.26600e-02	1.743e-02	Conversion electron
2.61250e-02	1.482e-02	Conversion electron
3.84038e-02	1.204e-02	Conversion electron
7.18676e-02	1.310e-02	Auger electron

 

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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