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Radionuclide Dosimetric Data Sheets

Selenium-73m

Isotope:  Se-73m
Atomic number (Z):  34
Mass number (A):  73
Neutron number (N):  39

Decay modes:  β+, Electron capture, Internal transition
Half-life:  39.8 [m]
Decay constant:  2.9026e-04 [1/s]
Daughters:  Se-73 (72.6%), As-73 (27.4%)
Radioactive daughters:  Se-73, As-73

Mean alpha energy:  0.0 [MeV]
Mean electron energy:  0.16421 [MeV]
Mean photon energy:  0.26325 [MeV]
Air kerma rate constant, Γ₁₀:  7.798e-18 [Gy·m²/Bq·s]
Air kerma coefficient, K_air:  1.570e-17 [Gy·m²/Bq·s]
Equilibrium dose constant for weakly-penetrating radiations (α and/or electrons), Δ_wp:  2.631e-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-:  2.631e-14 [Gy·kg/Bq·s]
Equilibrium dose constant for photons, Δ_p:  4.218e-14 [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/Se-73m 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/Se-73m 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/Se-73m 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/Se-73m Summary Spectrum.csv

 

Energy [MeV]	Yield [#/nt] if > 0.01	Radiation type
1.42085e-05	6.404e-01	X-ray
1.58606e-05	4.073e+00	X-ray
1.04633e-02	1.188e-02	X-ray
1.05007e-02	2.300e-02	X-ray
1.11378e-02	2.398e-02	X-ray
1.11804e-02	4.639e-02	X-ray
6.70700e-02	2.592e-02	Gamma
8.40000e-02	2.026e-02	Gamma
2.53700e-01	2.356e-02	Gamma
3.93430e-01	1.626e-02	Gamma
4.01470e-01	1.249e-02	Gamma
5.11000e-01	4.082e-01	Annihilation photon
7.28661e-01	1.259e-02	Positron
7.36454e-01	2.497e-02	Positron
7.67081e-01	1.289e-01	Positron
2.23274e-05	3.019e-01	Auger electron
3.24996e-05	1.888e+00	Auger electron
5.24626e-05	1.113e-01	Auger electron
5.41513e-05	6.975e-01	Auger electron
7.30819e-05	4.348e-02	Auger electron
9.86180e-05	1.847e-02	Auger electron
1.15647e-03	9.323e-02	Auger electron
1.23498e-03	6.287e-01	Auger electron
1.30861e-03	2.896e-02	Auger electron
9.06608e-03	2.414e-02	Auger electron
9.62662e-03	4.319e-02	Auger electron
1.09573e-02	1.273e-02	Auger electron
1.30910e-02	1.373e-01	Conversion electron
2.42288e-02	1.877e-01	Conversion electron
2.42714e-02	3.039e-01	Conversion electron
2.55463e-02	8.221e-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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