Nuclide reference

Hf-172 — Hafnium-172

Hf-172 की half-life 1.87 years है। मुख्य decay mode: electron capture → Lu-172m (100%)।

Identification

तत्व
Hafnium (Hf)
Atomic number Z
72
Mass number A
172
State
Radioactive

Key quantities

Half-life
1.87 years
विशिष्ट गतिविधि
4.112e+13 Bq/g
Gamma constant Γ
—
परिवहन के लिए A1 / A2 (SSR-6)
0.6 TBq / 0.6 TBq
D-value (НП-067-24)
0.04 TBq

Decay modes

  • electron capture → Lu-172m — 100 %

Main gamma lines

Energy, keVYield, %
1,093.63 (Lu-172)63.12
54.07 · X-ray line62.55
52.389 (Lu-172) · X-ray line56.34
900.724 (Lu-172)30.11
181.525 (Lu-172)20.77
23.933120.34
810.064 (Lu-172)16.79
912.079 (Lu-172)15.4
125.81211.3
78.7426 (Lu-172)10.67

Includes daughter nuclides in equilibrium: Lu-172 (yield per decay of Hf-172); the emitting nuclide is in brackets. Equilibrium is reached in about 47 d. In transient equilibrium a daughter's activity exceeds the parent's, so a yield can be above 100%.

Alpha and beta particles

RadiationEnergy, keVYield, %
β⁺, E max1,236 (Lu-172)0.0202

For β⁺ the endpoint (maximum) energy of the spectrum is given. ENDF/B-VIII.0.

Related calculators

Reference data vs computed valuesHalf-life, gamma lines and D-value are reference data (ENDF/B-VIII.0, НП-067-24).Gamma constant Γ 1 m पर H*(10) है, ICRP-107 spectra (NIST µ_en/ρ, ICRP-74 Table A.21) से गणना की गई, equilibrium में short-lived progeny सहित (जैसे Cs-137/Ba-137m, Ra-226 series); specific activity molar mass M ≈ mass number A का उपयोग करती है।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.

Hafnium-172 (Hf-172) — reference data

What is in the card

This card gathers the key data of radionuclide Hf-172 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 Hf-172 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.