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Radionuclide Dosimetric Data Sheets

Iridium-187

Summary data

General

Classification

Isotope:  Ir-187
Atomic number (Z):  77
Mass number (A):  187
Neutron number (N):  110

Radioactive decay

Decay modes:  β+, Electron capture
Half-life:  10.5 [h]
Decay constant:  1.8337e-05 [1/s]
Daughters:  Os-187 (100.0%)
Radioactive daughters:  None

Dosimetric constants

Mean alpha energy:  0.0 [MeV]
Mean electron energy:  0.05677 [MeV]
Mean photon energy:  0.33245 [MeV]
Air kerma rate constant, Γ10:  2.290e-17 [Gy·m2/Bq·s]
Air kerma coefficient, Kair:  2.291e-17 [Gy·m2/Bq·s]
Equilibrium dose constant for weakly-penetrating radiations (α and/or electrons), Δwp:  9.096e-15 [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-:  9.096e-15 [Gy·kg/Bq·s]
Equilibrium dose constant for photons, Δp:  5.326e-14 [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/Ir-187 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/Ir-187 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/Ir-187 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/Ir-187 Summary Spectrum.csv

 

Energy [MeV]

Yield [#/nt] if > 0.01

Radiation type

4.34747e-05

1.694e+01

X-ray

1.92869e-03

6.891e-02

X-ray

7.84700e-03

1.182e-02

X-ray

8.83249e-03

2.032e-02

X-ray

8.90608e-03

1.792e-01

X-ray

1.03795e-02

1.201e-01

X-ray

1.05947e-02

3.246e-02

X-ray

1.21269e-02

2.290e-02

X-ray

6.16420e-02

2.793e-01

X-ray

6.31890e-02

4.812e-01

X-ray

7.12758e-02

5.224e-02

X-ray

7.16144e-02

1.010e-01

X-ray

7.35200e-02

1.203e-02

X-ray

7.35997e-02

2.339e-02

X-ray

7.43000e-02

1.883e-02

Gamma

1.77680e-01

2.467e-02

Gamma

1.87370e-01

1.664e-02

Gamma

4.00810e-01

3.942e-02

Gamma

4.27020e-01

4.117e-02

Gamma

4.91740e-01

1.270e-02

Gamma

5.01510e-01

1.460e-02

Gamma

6.10880e-01

3.927e-02

Gamma

9.12860e-01

4.789e-02

Gamma

9.77540e-01

3.139e-02

Gamma

9.87350e-01

2.803e-02

Gamma

2.96221e-05

3.417e+00

Auger electron

1.63783e-04

5.620e+00

Auger electron

2.34008e-04

1.370e-01

Conversion electron

3.49597e-04

1.400e+00

Auger electron

3.54969e-04

2.389e-01

Auger electron

6.08364e-04

2.832e-01

Auger electron

1.59309e-03

2.518e+00

Auger electron

1.80365e-03

2.018e-01

Auger electron

2.10197e-03

1.069e-02

Auger electron

6.89232e-03

6.456e-01

Auger electron

7.29830e-03

4.467e-01

Conversion electron

8.79207e-03

2.564e-01

Auger electron

9.75000e-03

1.315e-01

Conversion electron

1.07215e-02

2.514e-02

Auger electron

1.26700e-02

7.071e-02

Conversion electron

2.31683e-02

1.844e-02

Conversion electron

4.99348e-02

2.758e-02

Auger electron

5.16400e-02

1.728e-02

Conversion electron

5.28860e-02

7.551e-02

Conversion electron

5.44330e-02

7.437e-02

Conversion electron

5.97656e-02

1.462e-02

Auger electron

6.13500e-02

2.015e-02

Conversion electron

6.26060e-02

3.681e-02

Conversion electron

6.28583e-02

3.940e-02

Conversion electron

6.41530e-02

3.500e-02

Conversion electron

6.53100e-02

1.119e-02

Conversion electron

7.25783e-02

1.874e-02

Conversion electron

1.03614e-01

1.955e-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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