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Radionuclide Dosimetric Data Sheets

Molybdenum-91

Isotope:  Mo-91
Atomic number (Z):  42
Mass number (A):  91
Neutron number (N):  49

Decay modes:  β+, Electron capture
Half-life:  15.49 [m]
Decay constant:  7.4580e-04 [1/s]
Daughters:  Nb-91 (100.0%), Nb-91m (0.0342%)
Radioactive daughters:  Nb-91, Nb-91m

Mean alpha energy:  0.0 [MeV]
Mean electron energy:  1.45096 [MeV]
Mean photon energy:  0.97729 [MeV]
Air kerma rate constant, Γ₁₀:  1.368e-18 [Gy·m²/Bq·s]
Air kerma coefficient, K_air:  3.765e-17 [Gy·m²/Bq·s]
Equilibrium dose constant for weakly-penetrating radiations (α and/or electrons), Δ_wp:  2.325e-13 [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-:  2.325e-13 [Gy·kg/Bq·s]
Equilibrium dose constant for photons, Δ_p:  1.566e-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/Mo-91 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/Mo-91 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/Mo-91 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/Mo-91 Summary Spectrum.csv

 

Energy [MeV]	Yield [#/nt] if > 0.01	Radiation type
5.83035e-06	6.836e-01	X-ray
1.64814e-02	1.184e-02	X-ray
1.65789e-02	2.261e-02	X-ray
5.11000e-01	1.875e+00	Annihilation photon
1.55116e+00	9.331e-01	Positron
2.53253e-05	3.366e-01	Auger electron
1.03505e-04	5.766e-02	Auger electron
1.07594e-04	1.254e-02	Auger electron
1.48960e-04	1.364e-01	Auger electron
1.85287e-03	5.492e-02	Auger 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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