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Radionuclide Dosimetric Data Sheets

Tungsten-187

Isotope:  W-187
Atomic number (Z):  74
Mass number (A):  187
Neutron number (N):  113

Decay modes:  β-
Half-life:  23.72 [h]
Decay constant:  8.1172e-06 [1/s]
Daughters:  Re-187 (100.0%)
Radioactive daughters:  Re-187

Mean alpha energy:  0.0 [MeV]
Mean electron energy:  0.29948 [MeV]
Mean photon energy:  0.44833 [MeV]
Air kerma rate constant, Γ₁₀:  1.876e-17 [Gy·m²/Bq·s]
Air kerma coefficient, K_air:  1.876e-17 [Gy·m²/Bq·s]
Equilibrium dose constant for weakly-penetrating radiations (α and/or electrons), Δ_wp:  4.798e-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-:  4.798e-14 [Gy·kg/Bq·s]
Equilibrium dose constant for photons, Δ_p:  7.183e-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/W-187 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/W-187 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/W-187 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/W-187 Summary Spectrum.csv

 

Energy [MeV]	Yield [#/nt] if > 0.01	Radiation type
3.75184e-05	2.787e+00	X-ray
1.84935e-03	1.108e-02	X-ray
8.64532e-03	3.561e-02	X-ray
1.00312e-02	2.253e-02	X-ray
5.98631e-02	7.319e-02	X-ray
6.13181e-02	1.265e-01	X-ray
6.91788e-02	1.368e-02	X-ray
6.94956e-02	2.643e-02	X-ray
7.20020e-02	1.114e-01	Gamma
1.34247e-01	8.845e-02	Gamma
4.79550e-01	2.184e-01	Gamma
5.51520e-01	5.078e-02	Gamma
6.18260e-01	6.279e-02	Gamma
6.25519e-01	1.089e-02	Gamma
6.85730e-01	2.730e-01	Gamma
7.72890e-01	4.122e-02	Gamma
1.62892e-01	4.268e-02	Beta
1.93372e-01	5.540e-01	Beta
2.14960e-01	3.330e-02	Beta
2.17547e-01	4.742e-02	Beta
4.56959e-01	3.007e-01	Beta
2.73022e-05	5.521e-01	Auger electron
1.46002e-04	7.949e-02	Conversion electron
1.62334e-04	9.351e-01	Auger electron
3.28827e-04	1.933e-01	Auger electron
3.30974e-04	3.511e-02	Auger electron
6.01917e-04	4.655e-02	Auger electron
1.52793e-03	4.373e-01	Auger electron
1.72085e-03	3.121e-02	Auger electron
4.73950e-03	1.583e-02	Conversion electron
6.67931e-03	1.327e-01	Auger electron
8.50418e-03	5.174e-02	Auger electron
6.23910e-02	1.669e-01	Conversion electron
1.21739e-01	2.426e-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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