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Radionuclide Dosimetric Data Sheets

Uranium-227

Summary data

General

Classification

Isotope:  U-227
Atomic number (Z):  92
Mass number (A):  227
Neutron number (N):  135

Radioactive decay

Decay modes:  α
Half-life:  1.1 [m]
Decay constant:  1.0502e-02 [1/s]
Daughters:  Th-223 (100.0%)
Radioactive daughters:  Th-223

Dosimetric constants

Mean alpha energy:  6.9978 [MeV]
Mean electron energy:  0.09604 [MeV]
Mean photon energy:  0.11986 [MeV]
Air kerma rate constant, Γ10:  1.278e-17 [Gy·m2/Bq·s]
Air kerma coefficient, Kair:  1.278e-17 [Gy·m2/Bq·s]
Equilibrium dose constant for weakly-penetrating radiations (α and/or electrons), Δwp:  1.137e-12 [Gy·kg/Bq·s]
Equilibrium dose constant for alphas, Δα:  1.121e-12 [Gy·kg/Bq·s]
Equilibrium dose constant for betas/electrons, Δβ-,β+,e-:  1.539e-14 [Gy·kg/Bq·s]
Equilibrium dose constant for photons, Δp:  1.920e-14 [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/U-227 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/U-227 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/U-227 Summary Spectrum.csv

 

Energy [MeV]

Yield [#/nt] if > 0.01

Radiation type

8.22445e-05

1.030e+01

X-ray

3.06231e-03

5.688e-02

X-ray

1.28126e-02

1.437e-02

X-ray

1.29764e-02

1.263e-01

X-ray

1.56384e-02

2.610e-02

X-ray

1.56464e-02

1.187e-02

X-ray

1.62776e-02

7.924e-02

X-ray

1.64418e-02

1.088e-02

X-ray

1.90652e-02

1.761e-02

X-ray

9.03299e-02

1.089e-01

X-ray

9.37949e-02

1.760e-01

X-ray

1.05278e-01

2.017e-02

X-ray

1.06073e-01

3.934e-02

X-ray

1.09154e-01

1.005e-02

X-ray

1.58000e-01

2.800e-02

Gamma

2.09000e-01

2.800e-02

Gamma

2.47000e-01

2.000e-01

Gamma

2.59000e-01

3.000e-02

Gamma

3.10000e-01

3.600e-02

Gamma

5.13188e-05

2.484e+00

Auger electron

1.32836e-04

2.743e+00

Auger electron

1.50455e-04

1.579e-02

Auger electron

1.88254e-04

1.549e+00

Auger electron

5.04905e-04

4.147e-01

Auger electron

1.40410e-03

2.075e-01

Auger electron

2.31453e-03

8.938e-01

Auger electron

2.72829e-03

1.533e-01

Auger electron

9.78561e-03

2.263e-01

Auger electron

1.29170e-02

1.126e-01

Auger electron

1.60862e-02

1.323e-02

Auger electron

3.08220e-02

1.753e-01

Conversion electron

3.15200e-02

6.196e-02

Conversion electron

3.49850e-02

3.942e-02

Conversion electron

4.72638e-02

6.951e-02

Conversion electron

4.78900e-02

4.935e-02

Conversion electron

5.13000e-02

2.444e-02

Conversion electron

9.88900e-02

2.322e-02

Conversion electron

1.36890e-01

2.492e-01

Conversion electron

1.38220e-01

1.175e-02

Conversion electron

1.48890e-01

3.275e-02

Conversion electron

1.99890e-01

2.395e-02

Conversion electron

2.26522e-01

4.191e-02

Conversion electron

2.42964e-01

1.123e-02

Conversion electron

6.77932e+00

1.600e-01

Alpha

6.84121e+00

5.000e-01

Alpha

6.87854e+00

1.400e-01

Alpha

7.03346e+00

2.000e-01

Alpha

1.21681e-01

1.600e-01

Alpha recoil

1.22792e-01

5.000e-01

Alpha recoil

1.23462e-01

1.400e-01

Alpha recoil

1.26243e-01

2.000e-01

Alpha recoil

 

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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