<= Return to MIRDspec isotope database
Radionuclide Dosimetric Data Sheets
Holmium-157
Summary data
General
Classification
Isotope: Ho-157
Atomic number (Z): 67
Mass number (A): 157
Neutron number (N): 90
Radioactive decay
Decay modes: β+, Electron capture
Half-life: 12.6 [m]
Decay constant: 9.1686e-04 [1/s]
Daughters: Dy-157 (100.0%)
Radioactive daughters: Dy-157
Dosimetric constants
Mean alpha energy: 0.0 [MeV]
Mean electron energy: 0.09288 [MeV]
Mean photon energy: 0.58349 [MeV]
Air kerma rate constant, Γ10: 2.077e-17 [Gy·m2/Bq·s]
Air kerma coefficient, Kair: 2.289e-17 [Gy·m2/Bq·s]
Equilibrium dose constant for weakly-penetrating radiations (α and/or
electrons), Δwp: 1.488e-14 [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-:
1.488e-14 [Gy·kg/Bq·s]
Equilibrium dose constant for photons, Δp: 9.349e-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/Ho-157 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/Ho-157 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/Ho-157 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/Ho-157 Summary Spectrum.csv
|
Energy [MeV] |
Yield [#/nt] if > 0.01 |
Radiation type |
|
1.37119e-05 |
1.756e+01 |
X-ray |
|
1.22940e-03 |
3.350e-02 |
X-ray |
|
5.76280e-03 |
1.089e-02 |
X-ray |
|
6.44440e-03 |
1.592e-02 |
X-ray |
|
6.48150e-03 |
1.407e-01 |
X-ray |
|
7.25411e-03 |
9.569e-02 |
X-ray |
|
7.35039e-03 |
1.125e-02 |
X-ray |
|
7.62077e-03 |
2.382e-02 |
X-ray |
|
8.42363e-03 |
1.679e-02 |
X-ray |
|
1.42300e-02 |
1.067e-02 |
Gamma |
|
4.52703e-02 |
4.134e-01 |
X-ray |
|
4.60801e-02 |
7.388e-01 |
X-ray |
|
5.20302e-02 |
7.604e-02 |
X-ray |
|
5.21989e-02 |
1.470e-01 |
X-ray |
|
5.35316e-02 |
1.674e-02 |
X-ray |
|
5.35696e-02 |
3.242e-02 |
X-ray |
|
6.11100e-02 |
5.334e-02 |
Gamma |
|
8.65500e-02 |
5.811e-02 |
Gamma |
|
1.47730e-01 |
2.043e-02 |
Gamma |
|
1.53090e-01 |
3.064e-02 |
Gamma |
|
1.62350e-01 |
1.407e-02 |
Gamma |
|
1.88050e-01 |
4.177e-02 |
Gamma |
|
1.93410e-01 |
7.264e-02 |
Gamma |
|
2.08700e-01 |
1.271e-02 |
Gamma |
|
2.34610e-01 |
1.022e-02 |
Gamma |
|
2.57880e-01 |
1.135e-02 |
Gamma |
|
2.72170e-01 |
4.290e-02 |
Gamma |
|
2.79970e-01 |
2.270e-01 |
Gamma |
|
3.20200e-01 |
1.816e-02 |
Gamma |
|
3.41160e-01 |
1.748e-01 |
Gamma |
|
5.08300e-01 |
2.996e-02 |
Gamma |
|
5.11000e-01 |
1.092e-01 |
Annihilation photon |
|
5.55500e-01 |
2.951e-02 |
Gamma |
|
7.08600e-01 |
1.362e-02 |
Gamma |
|
8.35300e-01 |
1.067e-02 |
Gamma |
|
8.96600e-01 |
3.995e-02 |
Gamma |
|
1.21110e+00 |
2.338e-02 |
Gamma |
|
5.61963e-01 |
3.337e-02 |
Positron |
|
1.81686e-05 |
9.731e-01 |
Auger electron |
|
1.28553e-04 |
8.014e+00 |
Auger electron |
|
1.55434e-04 |
3.944e-01 |
Auger electron |
|
2.09777e-04 |
1.293e+00 |
Auger electron |
|
6.59885e-04 |
2.656e-01 |
Auger electron |
|
1.01704e-03 |
2.786e+00 |
Auger electron |
|
1.19293e-03 |
1.515e-01 |
Auger electron |
|
5.12623e-03 |
9.952e-01 |
Auger electron |
|
5.21750e-03 |
2.227e-02 |
Conversion electron |
|
5.63930e-03 |
2.891e-02 |
Conversion electron |
|
6.38937e-03 |
3.503e-01 |
Auger electron |
|
6.44900e-03 |
4.578e-02 |
Conversion electron |
|
7.24901e-03 |
4.490e-01 |
Conversion electron |
|
7.68657e-03 |
3.104e-02 |
Auger electron |
|
1.25679e-02 |
2.235e-02 |
Conversion electron |
|
1.82890e-02 |
1.260e-02 |
Conversion electron |
|
3.26890e-02 |
1.800e-01 |
Conversion electron |
|
3.70640e-02 |
5.881e-02 |
Auger electron |
|
4.01375e-02 |
1.776e-02 |
Conversion electron |
|
4.39727e-02 |
2.942e-02 |
Auger electron |
|
5.20975e-02 |
6.046e-02 |
Conversion electron |
|
5.25193e-02 |
1.713e-02 |
Conversion electron |
|
5.33290e-02 |
1.434e-02 |
Conversion electron |
|
5.59990e-02 |
1.007e-02 |
Conversion electron |
|
5.94479e-02 |
2.074e-02 |
Conversion electron |
|
7.75375e-02 |
2.403e-02 |
Conversion electron |
|
1.39549e-01 |
2.351e-02 |
Conversion electron |
|
2.26109e-01 |
2.684e-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
MIRDsoft MIRDspecs version 20250101 (www.mirdsoft.org)
<= Return to MIRDspec isotope database
