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Radionuclide Dosimetric Data Sheets

Protactinium-232

Summary data

General

Classification

Isotope:  Pa-232
Atomic number (Z):  91
Mass number (A):  232
Neutron number (N):  141

Radioactive decay

Decay modes:  β-, Electron capture
Half-life:  1.31 [d]
Decay constant:  6.1241e-06 [1/s]
Daughters:  U-232 (100.0%), Th-232 (0.003%)
Radioactive daughters:  U-232, Th-232

Dosimetric constants

Mean alpha energy:  0.0 [MeV]
Mean electron energy:  0.1738 [MeV]
Mean photon energy:  0.93929 [MeV]
Air kerma rate constant, Γ10:  4.511e-17 [Gy·m2/Bq·s]
Air kerma coefficient, Kair:  4.511e-17 [Gy·m2/Bq·s]
Equilibrium dose constant for weakly-penetrating radiations (α and/or electrons), Δwp:  2.785e-14 [Gy·kg/Bq·s]
Equilibrium dose constant for alphas, Δα:  0.000e+00 [Gy·kg/Bq·s]
Equilibrium dose constant for betas/electrons, Δβ-,β+,e-:  2.785e-14 [Gy·kg/Bq·s]
Equilibrium dose constant for photons, Δp:  1.505e-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/Pa-232 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/Pa-232 Summary Spectrum.csv

Beta spectra (plot)

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-232 Beta 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/Pa-232 Summary Spectrum.csv

 

Energy [MeV]

Yield [#/nt] if > 0.01

Radiation type

7.55221e-05

1.276e+01

X-ray

3.26018e-03

7.793e-02

X-ray

1.16607e-02

1.141e-02

X-ray

1.34452e-02

1.859e-02

X-ray

1.36268e-02

1.633e-01

X-ray

1.64468e-02

3.425e-02

X-ray

1.73072e-02

1.736e-01

X-ray

2.02658e-02

3.933e-02

X-ray

9.50660e-02

1.117e-02

X-ray

9.89281e-02

1.787e-02

X-ray

1.05470e-01

1.646e-02

Gamma

1.08960e-01

2.807e-02

Gamma

1.50059e-01

1.084e-01

Gamma

1.84101e-01

1.258e-02

Gamma

3.87884e-01

6.970e-02

Gamma

4.21932e-01

2.517e-02

Gamma

4.53655e-01

8.615e-02

Gamma

4.72390e-01

4.162e-02

Gamma

5.15607e-01

5.518e-02

Gamma

5.63197e-01

3.678e-02

Gamma

5.81398e-01

6.002e-02

Gamma

8.19187e-01

7.454e-02

Gamma

8.63890e-01

1.936e-02

Gamma

8.66760e-01

5.808e-02

Gamma

8.94351e-01

1.984e-01

Gamma

9.69315e-01

4.162e-01

Gamma

7.91246e-02

2.413e-01

Beta

8.94034e-02

7.066e-01

Beta

7.21814e-05

3.436e+00

Auger electron

1.63132e-04

2.193e-02

Auger electron

1.86419e-04

3.366e+00

Auger electron

1.92507e-04

1.933e+00

Auger electron

5.41471e-04

4.963e-01

Auger electron

1.21093e-03

1.283e-01

Auger electron

2.44400e-03

1.110e+00

Auger electron

2.91673e-03

2.087e-01

Auger electron

3.53677e-03

1.229e-02

Auger electron

1.02903e-02

2.782e-01

Auger electron

1.36227e-02

1.416e-01

Auger electron

1.69911e-02

1.697e-02

Auger electron

2.58820e-02

1.237e-02

Conversion electron

2.66060e-02

3.576e-01

Conversion electron

3.04680e-02

3.108e-01

Conversion electron

3.39490e-02

1.636e-02

Conversion electron

4.33604e-02

1.884e-01

Conversion electron

4.76500e-02

6.627e-02

Conversion electron

8.79160e-02

1.089e-01

Conversion electron

9.17780e-02

7.169e-02

Conversion electron

1.04670e-01

5.207e-02

Conversion electron

1.08960e-01

1.832e-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

 

 

 

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