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Radionuclide Dosimetric Data Sheets

Samarium-139

Summary data

General

Classification

Isotope:  Sm-139
Atomic number (Z):  62
Mass number (A):  139
Neutron number (N):  77

Radioactive decay

Decay modes:  β+, Electron capture
Half-life:  2.57 [m]
Decay constant:  4.4951e-03 [1/s]
Daughters:  Pm-139 (100.0%)
Radioactive daughters:  Pm-139

Dosimetric constants

Mean alpha energy:  0.0 [MeV]
Mean electron energy:  1.08707 [MeV]
Mean photon energy:  1.45395 [MeV]
Air kerma rate constant, Γ10:  2.749e-17 [Gy·m2/Bq·s]
Air kerma coefficient, Kair:  5.394e-17 [Gy·m2/Bq·s]
Equilibrium dose constant for weakly-penetrating radiations (α and/or electrons), Δwp:  1.742e-13 [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-:  1.742e-13 [Gy·kg/Bq·s]
Equilibrium dose constant for photons, Δp:  2.329e-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/Sm-139 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/Sm-139 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/Sm-139 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/Sm-139 Summary Spectrum.csv

 

Energy [MeV]

Yield [#/nt] if > 0.01

Radiation type

1.48555e-05

4.558e+00

X-ray

5.41729e-03

2.271e-02

X-ray

5.95960e-03

1.471e-02

X-ray

3.30000e-02

1.010e-02

Gamma

3.81996e-02

8.524e-02

X-ray

3.87671e-02

1.547e-01

X-ray

4.37575e-02

1.540e-02

X-ray

4.38721e-02

2.979e-02

X-ray

1.88900e-01

2.701e-02

Gamma

2.28000e-01

2.993e-02

Gamma

2.34600e-01

1.095e-02

Gamma

2.73700e-01

3.650e-01

Gamma

3.06700e-01

2.847e-01

Gamma

3.15700e-01

1.387e-02

Gamma

4.47500e-01

3.212e-02

Gamma

4.75300e-01

2.482e-02

Gamma

5.08500e-01

4.745e-02

Gamma

5.11000e-01

1.367e+00

Annihilation photon

5.89500e-01

1.898e-02

Gamma

5.96300e-01

8.030e-02

Gamma

6.55300e-01

3.614e-02

Gamma

6.55800e-01

2.883e-02

Gamma

7.41900e-01

2.664e-02

Gamma

7.82000e-01

6.935e-02

Gamma

8.62200e-01

1.935e-02

Gamma

9.10100e-01

1.789e-02

Gamma

1.01570e+00

1.642e-02

Gamma

1.67520e+00

1.314e-02

Gamma

2.21000e+00

1.570e-02

Gamma

1.20137e+00

1.137e-02

Positron

1.32013e+00

1.496e-02

Positron

1.39775e+00

3.191e-02

Positron

1.43765e+00

2.692e-02

Positron

1.43938e+00

1.296e-02

Positron

1.46890e+00

1.356e-02

Positron

1.50611e+00

1.067e-01

Positron

1.53431e+00

2.084e-02

Positron

1.56504e+00

2.792e-02

Positron

1.59252e+00

4.986e-02

Positron

1.59570e+00

2.792e-02

Positron

1.72775e+00

2.254e-01

Positron

1.74318e+00

3.889e-02

Positron

1.43706e-05

4.005e-01

Auger electron

8.58156e-05

3.718e-01

Auger electron

1.00484e-04

1.825e+00

Auger electron

1.59862e-04

3.013e-01

Auger electron

4.90546e-04

7.552e-02

Auger electron

7.57082e-04

6.214e-01

Auger electron

9.25495e-04

4.140e-02

Auger electron

4.32758e-03

2.334e-01

Auger electron

5.33074e-03

7.929e-02

Auger electron

2.56059e-02

4.475e-02

Conversion electron

3.14373e-02

1.551e-02

Auger electron

3.16531e-02

1.056e-02

Conversion electron

2.28481e-01

2.570e-02

Conversion electron

2.61481e-01

1.140e-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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