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Radionuclide Dosimetric Data Sheets

Cerium-133m

Summary data

General

Classification

Isotope:  Ce-133m
Atomic number (Z):  58
Mass number (A):  133
Neutron number (N):  75

Radioactive decay

Decay modes:  β+, Electron capture
Half-life:  4.9 [h]
Decay constant:  3.9294e-05 [1/s]
Daughters:  La-133 (100.0%)
Radioactive daughters:  La-133

Dosimetric constants

Mean alpha energy:  0.0 [MeV]
Mean electron energy:  0.07393 [MeV]
Mean photon energy:  1.73728 [MeV]
Air kerma rate constant, Γ10:  6.232e-17 [Gy·m2/Bq·s]
Air kerma coefficient, Kair:  6.418e-17 [Gy·m2/Bq·s]
Equilibrium dose constant for weakly-penetrating radiations (α and/or electrons), Δwp:  1.184e-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-:  1.184e-14 [Gy·kg/Bq·s]
Equilibrium dose constant for photons, Δp:  2.783e-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/Ce-133m 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/Ce-133m 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/Ce-133m 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/Ce-133m Summary Spectrum.csv

 

Energy [MeV]

Yield [#/nt] if > 0.01

Radiation type

2.10725e-05

1.712e+01

X-ray

4.63652e-03

6.174e-02

X-ray

5.03753e-03

3.675e-02

X-ray

5.37004e-03

1.010e-02

X-ray

3.30405e-02

3.025e-01

X-ray

3.34591e-02

5.555e-01

X-ray

3.77381e-02

5.354e-02

X-ray

3.78203e-02

1.037e-01

X-ray

3.87183e-02

1.136e-02

X-ray

3.87359e-02

2.212e-02

X-ray

5.83900e-02

1.925e-01

Gamma

8.79390e-02

5.135e-02

Gamma

9.72610e-02

1.756e-02

Gamma

1.30803e-01

1.791e-01

Gamma

1.78650e-01

1.215e-02

Gamma

2.48950e-01

1.333e-02

Gamma

2.61396e-01

1.740e-02

Gamma

3.46390e-01

4.155e-02

Gamma

3.64190e-01

1.254e-02

Gamma

4.04780e-01

1.697e-02

Gamma

4.32550e-01

3.528e-02

Gamma

4.44200e-01

1.372e-02

Gamma

4.75490e-01

3.175e-02

Gamma

4.77220e-01

3.920e-01

Gamma

5.10360e-01

2.070e-01

Gamma

5.11000e-01

9.637e-02

Annihilation photon

5.23760e-01

3.136e-02

Gamma

5.41090e-01

2.940e-02

Gamma

6.11830e-01

2.595e-02

Gamma

6.17700e-01

1.646e-02

Gamma

6.44740e-01

1.968e-02

Gamma

6.89480e-01

4.116e-02

Gamma

7.84550e-01

9.643e-02

Gamma

8.29420e-01

1.007e-02

Gamma

9.50990e-01

1.274e-02

Gamma

9.90130e-01

2.940e-02

Gamma

1.18333e+00

1.098e-02

Gamma

1.19990e+00

1.568e-02

Gamma

1.37722e+00

1.725e-02

Gamma

1.43222e+00

1.200e-02

Gamma

1.49485e+00

3.214e-02

Gamma

1.50041e+00

4.743e-02

Gamma

1.52656e+00

2.470e-02

Gamma

1.58462e+00

2.391e-02

Gamma

1.72020e+00

1.282e-02

Gamma

1.76936e+00

1.219e-02

Gamma

1.88730e+00

1.015e-02

Gamma

2.01823e+00

1.364e-02

Gamma

2.11920e+00

1.254e-02

Gamma

8.83695e-01

1.539e-02

Positron

1.18532e-05

2.990e+00

Auger electron

3.33700e-05

2.464e-02

Auger electron

6.07189e-05

5.959e+00

Auger electron

6.29238e-05

1.888e+00

Auger electron

1.17773e-04

8.428e-01

Auger electron

3.55064e-04

1.805e-01

Auger electron

5.79555e-04

2.001e+00

Auger electron

7.30056e-04

1.726e-01

Auger electron

3.69615e-03

7.862e-01

Auger electron

4.50972e-03

2.600e-01

Auger electron

5.35437e-03

2.042e-02

Auger electron

1.94470e-02

1.659e-01

Conversion electron

2.73123e-02

6.949e-02

Auger electron

3.21336e-02

3.251e-02

Auger electron

4.89960e-02

7.018e-02

Conversion electron

5.21482e-02

1.571e-02

Conversion electron

5.83180e-02

1.809e-02

Conversion electron

9.18600e-02

7.996e-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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