Nuclide reference

Th-234 — Thorium-234

Th-234 की half-life 24.1 d है। मुख्य decay mode: β⁻ decay → Pa-234m (100%)।

Identification

तत्व
Thorium (Th)
Atomic number Z
90
Mass number A
234
State
Radioactive

Key quantities

Half-life
24.1 d
विशिष्ट गतिविधि
8.567e+14 Bq/g
Gamma constant Γ
—
परिवहन के लिए A1 / A2 (SSR-6)
0.3 TBq / 0.3 TBq
D-value (НП-067-24)
2 TBq

Decay modes

Main gamma lines

Energy, keVYield, %
13.3 · X-ray line7.04
63.293.665
92.382.13
92.82.1
1,001.03 (Pa-234m)0.8417
766.42 (Pa-234m)0.3173
112.810.21
742.813 (Pa-234m)0.1066
258.227 (Pa-234m)0.07642
17.0955 (Pa-234) · X-ray line0.07139

Includes daughter nuclides in equilibrium: Pa-234m, Pa-234 (yield per decay of Th-234); the emitting nuclide is in brackets. Equilibrium is reached in about 47 h.

Alpha and beta particles

RadiationEnergy, keVYield, %
β⁻, E max199.0878
106.714
106.286.4
2,273.9 (Pa-234m)97.57

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.

Thorium-234 (Th-234) — reference data

What is in the card

This card gathers the key data of radionuclide Th-234 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 Th-234 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.