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Radionuclide Dosimetric Data Sheets

Niobium-90

Isotope:  Nb-90
Atomic number (Z):  41
Mass number (A):  90
Neutron number (N):  49

Decay modes:  β+, Electron capture
Half-life:  14.6 [h]
Decay constant:  1.3188e-05 [1/s]
Daughters:  Zr-90 (100.0%)
Radioactive daughters:  None

Mean alpha energy:  0.0 [MeV]
Mean electron energy:  0.40318 [MeV]
Mean photon energy:  4.21354 [MeV]
Air kerma rate constant, Γ₁₀:  1.237e-16 [Gy·m²/Bq·s]
Air kerma coefficient, K_air:  1.445e-16 [Gy·m²/Bq·s]
Equilibrium dose constant for weakly-penetrating radiations (α and/or electrons), Δ_wp:  6.460e-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-:  6.460e-14 [Gy·kg/Bq·s]
Equilibrium dose constant for photons, Δ_p:  6.751e-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/Nb-90 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/Nb-90 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/Nb-90 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/Nb-90 Summary Spectrum.csv

 

Energy [MeV]	Yield [#/nt] if > 0.01	Radiation type
6.52415e-06	9.577e+00	X-ray
2.03430e-03	1.438e-02	X-ray
1.56498e-02	1.433e-01	X-ray
1.57372e-02	2.742e-01	X-ray
1.76171e-02	2.162e-02	X-ray
1.76312e-02	4.210e-02	X-ray
1.32716e-01	4.134e-02	Gamma
1.41178e-01	6.677e-01	Gamma
3.71307e-01	1.805e-02	Gamma
5.11000e-01	1.075e+00	Annihilation photon
8.27740e-01	1.107e-02	Gamma
8.90640e-01	1.805e-02	Gamma
1.12922e+00	9.269e-01	Gamma
1.27040e+00	1.296e-02	Gamma
1.61176e+00	2.379e-02	Gamma
1.91319e+00	1.280e-02	Gamma
2.18624e+00	1.796e-01	Gamma
2.31896e+00	8.203e-01	Gamma
6.62140e-01	5.367e-01	Positron
2.22377e-05	5.077e+00	Auger electron
9.84963e-05	7.607e-01	Auger electron
1.05573e-04	1.539e-01	Auger electron
1.17869e-04	1.739e+00	Auger electron
1.58123e-04	5.134e-02	Auger electron
1.75393e-03	7.233e-01	Auger electron
1.94461e-03	8.107e-02	Auger electron
1.33271e-02	1.331e-01	Auger electron
1.53342e-02	4.739e-02	Auger electron
1.14754e-01	9.233e-02	Conversion electron
1.23216e-01	1.801e-01	Conversion electron
1.30491e-01	1.017e-02	Conversion electron
1.38663e-01	1.728e-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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