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Radionuclide Dosimetric Data Sheets

Astatine-209

Summary data

General

Classification

Isotope:  At-209
Atomic number (Z):  85
Mass number (A):  209
Neutron number (N):  124

Radioactive decay

Decay modes:  α, β+, Electron capture
Half-life:  5.41 [h]
Decay constant:  3.5590e-05 [1/s]
Daughters:  Po-209 (95.9%), Bi-205 (4.1%)
Radioactive daughters:  Po-209, Bi-205

Dosimetric constants

Mean alpha energy:  0.236 [MeV]
Mean electron energy:  0.11717 [MeV]
Mean photon energy:  2.28462 [MeV]
Air kerma rate constant, Γ10:  1.053e-16 [Gy·m2/Bq·s]
Air kerma coefficient, Kair:  1.053e-16 [Gy·m2/Bq·s]
Equilibrium dose constant for weakly-penetrating radiations (α and/or electrons), Δwp:  5.658e-14 [Gy·kg/Bq·s]
Equilibrium dose constant for alphas, Δα:  3.781e-14 [Gy·kg/Bq·s]
Equilibrium dose constant for betas/electrons, Δβ-,β+,e-:  1.877e-14 [Gy·kg/Bq·s]
Equilibrium dose constant for photons, Δp:  3.660e-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/At-209 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/At-209 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/At-209 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/At-209 Summary Spectrum.csv

 

Energy [MeV]

Yield [#/nt] if > 0.01

Radiation type

3.84127e-05

2.186e+01

X-ray

2.54303e-03

9.257e-02

X-ray

9.68940e-03

1.570e-02

X-ray

1.10135e-02

2.746e-02

X-ray

1.11319e-02

2.416e-01

X-ray

1.30778e-02

1.086e-02

X-ray

1.33474e-02

4.737e-02

X-ray

1.34935e-02

1.700e-01

X-ray

1.36365e-02

1.140e-02

X-ray

1.58015e-02

3.550e-02

X-ray

7.71271e-02

3.393e-01

X-ray

7.96070e-02

5.648e-01

X-ray

8.95836e-02

6.340e-02

X-ray

9.01425e-02

1.230e-01

X-ray

9.08000e-02

1.838e-02

Gamma

9.25794e-02

1.529e-02

X-ray

9.27190e-02

3.018e-02

X-ray

1.04187e-01

2.366e-02

Gamma

1.95000e-01

2.257e-01

Gamma

2.39190e-01

1.237e-01

Gamma

5.45000e-01

9.099e-01

Gamma

5.51000e-01

4.913e-02

Gamma

5.52500e-01

1.547e-02

Gamma

6.66100e-01

1.865e-02

Gamma

7.81900e-01

8.353e-01

Gamma

7.90200e-01

6.351e-01

Gamma

8.63900e-01

2.065e-02

Gamma

9.03000e-01

3.649e-02

Gamma

1.10340e+00

5.405e-02

Gamma

1.14760e+00

1.365e-02

Gamma

1.17060e+00

3.094e-02

Gamma

1.17530e+00

1.911e-02

Gamma

1.21720e+00

1.110e-02

Gamma

1.26260e+00

1.893e-02

Gamma

1.58160e+00

1.792e-02

Gamma

3.94678e-05

5.225e+00

Auger electron

9.72190e-05

6.808e+00

Auger electron

1.22183e-04

1.324e-02

Auger electron

1.74789e-04

3.665e+00

Auger electron

4.36043e-04

8.535e-01

Auger electron

1.10021e-03

2.803e-01

Auger electron

2.01559e-03

1.983e+00

Auger electron

2.30938e-03

2.729e-01

Auger electron

2.73953e-03

1.424e-02

Auger electron

8.48591e-03

5.682e-01

Auger electron

1.07630e-02

1.388e-01

Conversion electron

1.10387e-02

2.597e-01

Auger electron

1.36210e-02

2.828e-02

Auger electron

6.18768e-02

2.752e-02

Auger electron

7.45030e-02

8.134e-02

Conversion electron

7.46184e-02

1.520e-02

Auger electron

7.69830e-02

6.512e-02

Conversion electron

8.72690e-02

2.263e-02

Conversion electron

8.75185e-02

4.011e-02

Conversion electron

8.78900e-02

2.049e-02

Conversion electron

9.03700e-02

1.415e-02

Conversion electron

9.08000e-02

1.277e-02

Conversion electron

1.00906e-01

1.459e-02

Conversion electron

1.01576e-01

3.223e-01

Conversion electron

1.78082e-01

5.095e-02

Conversion electron

1.91719e-01

1.347e-02

Conversion electron

4.51576e-01

1.708e-02

Conversion electron

5.64704e+00

4.096e-02

Alpha

1.10258e-01

4.096e-02

Alpha recoil

 

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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