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Radionuclide Dosimetric Data Sheets

Protactinium-234m

Isotope:  Pa-234m
Atomic number (Z):  91
Mass number (A):  234
Neutron number (N):  143

Decay modes:  β-, Internal transition
Half-life:  1.17 [m]
Decay constant:  9.8739e-03 [1/s]
Daughters:  U-234 (99.8%), Pa-234 (0.16%)
Radioactive daughters:  U-234, Pa-234

Mean alpha energy:  0.0 [MeV]
Mean electron energy:  0.81712 [MeV]
Mean photon energy:  0.01623 [MeV]
Air kerma rate constant, Γ₁₀:  7.374e-19 [Gy·m²/Bq·s]
Air kerma coefficient, K_air:  7.374e-19 [Gy·m²/Bq·s]
Equilibrium dose constant for weakly-penetrating radiations (α and/or electrons), Δ_wp:  1.309e-13 [Gy·kg/Bq·s]
Equilibrium dose constant for alphas, Δ_α:  0.000e+00 [Gy·kg/Bq·s]
Equilibrium dose constant for betas/electrons, Δ_β-,β+,e-:  1.309e-13 [Gy·kg/Bq·s]
Equilibrium dose constant for photons, Δ_p:  2.600e-15 [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-234m 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-234m 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/Pa-234m 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/Pa-234m Summary Spectrum.csv

 

Energy [MeV]	Yield [#/nt] if > 0.01	Radiation type
7.54941e-05	1.749e-01	X-ray
7.66335e-05	2.833e-02	X-ray
4.07074e-01	1.003e-02	Beta
8.22029e-01	9.785e-01	Beta
7.22036e-05	4.709e-02	Auger electron
1.85783e-04	4.614e-02	Auger electron
1.92276e-04	2.638e-02	Auger electron
2.43694e-03	1.526e-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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