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Radionuclide Dosimetric Data Sheets

Thallium-206m

Summary data

General

Classification

Isotope:  Tl-206m
Atomic number (Z):  81
Mass number (A):  206
Neutron number (N):  125

Radioactive decay

Decay modes:  Internal transition
Half-life:  3.74 [m]
Decay constant:  3.0889e-03 [1/s]
Daughters:  Tl-206 (100.0%)
Radioactive daughters:  Tl-206

Dosimetric constants

Mean alpha energy:  0.0 [MeV]
Mean electron energy:  0.20034 [MeV]
Mean photon energy:  2.4192 [MeV]
Air kerma rate constant, Γ10:  9.711e-17 [Gy·m2/Bq·s]
Air kerma coefficient, Kair:  9.711e-17 [Gy·m2/Bq·s]
Equilibrium dose constant for weakly-penetrating radiations (α and/or electrons), Δwp:  3.210e-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-:  3.210e-14 [Gy·kg/Bq·s]
Equilibrium dose constant for photons, Δp:  3.876e-13 [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/Tl-206m 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/Tl-206m Summary 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/Tl-206m Summary Spectrum.csv

 

Energy [MeV]

Yield [#/nt] if > 0.01

Radiation type

2.07421e-05

8.144e+00

X-ray

2.30260e-03

2.855e-02

X-ray

1.02661e-02

7.646e-02

X-ray

1.22523e-02

6.401e-02

X-ray

1.22749e-02

1.457e-02

X-ray

1.43397e-02

1.293e-02

X-ray

7.10519e-02

1.028e-01

X-ray

7.31380e-02

1.734e-01

X-ray

8.23883e-02

1.924e-02

X-ray

8.28534e-02

3.725e-02

X-ray

2.16400e-01

7.396e-01

Gamma

2.47200e-01

8.600e-02

Gamma

2.65700e-01

8.600e-01

Gamma

3.04900e-01

1.290e-02

Gamma

3.68200e-01

1.032e-02

Gamma

4.53300e-01

9.288e-01

Gamma

4.57200e-01

2.236e-01

Gamma

5.35500e-01

1.376e-02

Gamma

5.64200e-01

5.160e-02

Gamma

6.04300e-01

1.032e-02

Gamma

6.86500e-01

9.030e-01

Gamma

7.04600e-01

1.462e-02

Gamma

1.02150e+00

6.880e-01

Gamma

1.13990e+00

6.020e-02

Gamma

4.30404e-05

1.788e+00

Auger electron

7.58248e-05

2.669e+00

Auger electron

1.74797e-04

1.403e+00

Auger electron

4.21397e-04

3.064e-01

Auger electron

9.77371e-04

8.369e-02

Auger electron

1.86220e-03

7.337e-01

Auger electron

2.10910e-03

8.651e-02

Auger electron

7.92216e-03

2.187e-01

Auger electron

1.02174e-02

9.528e-02

Auger electron

1.30602e-01

1.039e-01

Conversion electron

1.61402e-01

3.171e-02

Conversion electron

1.79902e-01

7.393e-02

Conversion electron

2.01070e-01

1.421e-02

Conversion electron

2.01654e-01

5.231e-02

Conversion electron

2.03740e-01

3.073e-02

Conversion electron

2.13455e-01

2.525e-02

Conversion electron

2.31002e-01

4.886e-02

Conversion electron

2.50370e-01

1.029e-02

Conversion electron

2.50954e-01

2.547e-02

Conversion electron

2.53040e-01

1.351e-02

Conversion electron

2.62755e-01

1.268e-02

Conversion electron

3.01470e-01

1.804e-02

Conversion electron

3.04140e-01

1.260e-02

Conversion electron

3.71402e-01

1.469e-02

Conversion electron

4.78402e-01

4.125e-02

Conversion electron

5.48870e-01

1.024e-02

Conversion electron

9.35702e-01

2.657e-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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