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Nuclide reference

Au-195m — Gold-195m

The half-life of Au-195m is 30.5 s. Main decay mode: isomeric transition to Au-195 (100%).

Identification

Element
Gold (Au)
Atomic number Z
79
Mass number A
195
State
Radioactive

Key quantities

Half-life
30.5 s
Specific activity
7.018e+19 Bq/g
Gamma constant Γ
—
D-value (НП-067-24)
—

Decay modes

  • isomeric transition → Au-195 — 100 %

Main gamma lines

Energy, keVYield, %
261.7568.7
11.4908 · X-ray line16.93
9.70119 · X-ray line15.13
200.381.657
61.460.1723
318.60.04392
56.80.03023

Lines of the bare nuclide (ENDF/B-VIII.0), without daughter ingrowth.

Related calculators

DecayActivity ↔ massDose rate
Reference data vs computed valuesHalf-life, gamma lines and D-value are reference data (ENDF/B-VIII.0, НП-067-24).Gamma constant Γ is H*(10) at 1 m computed from ICRP-107 spectra (NIST µ_en/ρ, ICRP-74 Table A.21) including short-lived progeny in equilibrium (e.g. Cs-137/Ba-137m, Ra-226 series); specific activity uses molar mass M ≈ mass number A.K-series X-ray energies are from NIST SRD 128 (Deslattes et al., 2003): in ENDF/B-VIII.0 they are given to 1 % and shifted by up to 0.7 keV for heavy elements. L-series lines and all yields are ENDF/B-VIII.0.

Gold-195m (Au-195m) — reference data

What is in the card

This card gathers the key data of radionuclide Au-195m in one place: half-life, decay modes, main gamma lines, alpha and beta particle energies, gamma constant, specific activity and the D-value for source categorization. Decay and emission data are from ENDF/B-VIII.0; the D-value follows NP-067-24; the gamma constant is the ambient dose equivalent H*(10) at 1 m, computed from ICRP-107 spectra.

How to use the data

Half-life and specific activity let you recalculate the activity of a Au-195m source to the delivery or disposal date — use the decay calculator. Gamma lines with yields identify the nuclide from a spectrum and pick the line for gamma spectrometry; the gamma constant Γ gives the dose rate at a distance, while the D-value and A1/A2 set the source category and the package type for transport.