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Radionuclide Dosimetric Data Sheets

Cesium-136

Isotope:  Cs-136
Atomic number (Z):  55
Mass number (A):  136
Neutron number (N):  81

Decay modes:  β-
Half-life:  13.16 [d]
Decay constant:  6.0962e-07 [1/s]
Daughters:  Ba-136 (100.0%)
Radioactive daughters:  None

Mean alpha energy:  0.0 [MeV]
Mean electron energy:  0.1449 [MeV]
Mean photon energy:  2.1283 [MeV]
Air kerma rate constant, Γ₁₀:  7.669e-17 [Gy·m²/Bq·s]
Air kerma coefficient, K_air:  7.669e-17 [Gy·m²/Bq·s]
Equilibrium dose constant for weakly-penetrating radiations (α and/or electrons), Δ_wp:  2.322e-14 [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-:  2.322e-14 [Gy·kg/Bq·s]
Equilibrium dose constant for photons, Δ_p:  3.410e-13 [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/Cs-136 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/Cs-136 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/Cs-136 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/Cs-136 Summary Spectrum.csv

 

Energy [MeV]	Yield [#/nt] if > 0.01	Radiation type
1.86046e-05	2.366e+00	X-ray
3.18187e-02	3.182e-02	X-ray
3.22056e-02	5.860e-02	X-ray
3.63920e-02	1.085e-02	X-ray
6.68810e-02	4.786e-02	Gamma
8.63600e-02	5.185e-02	Gamma
1.53246e-01	5.753e-02	Gamma
1.63920e-01	3.390e-02	Gamma
1.76602e-01	9.970e-02	Gamma
2.73646e-01	1.107e-01	Gamma
3.40547e-01	4.217e-01	Gamma
8.18514e-01	9.970e-01	Gamma
1.04807e+00	7.976e-01	Gamma
1.23536e+00	2.004e-01	Gamma
4.72526e-02	2.021e-02	Beta
9.87613e-02	6.964e-01	Beta
1.20961e-01	1.040e-01	Beta
1.50721e-01	4.656e-02	Beta
2.18948e-01	1.288e-01	Beta
1.08630e-05	5.044e-01	Auger electron
4.67906e-05	2.910e-01	Auger electron
4.87827e-05	8.020e-01	Auger electron
1.15438e-04	1.144e-01	Auger electron
3.20395e-04	2.002e-02	Auger electron
5.51913e-04	2.638e-01	Auger electron
6.89481e-04	1.939e-02	Auger electron
3.56705e-03	1.031e-01	Auger electron
4.33245e-03	3.294e-02	Auger electron
2.94320e-02	2.804e-02	Conversion electron
4.89110e-02	1.512e-02	Conversion electron
1.15797e-01	1.821e-02	Conversion electron
1.26471e-01	3.737e-02	Conversion electron
1.58290e-01	1.478e-02	Conversion electron
1.58677e-01	1.234e-02	Conversion electron
3.03098e-01	1.056e-02	Conversion 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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