Search results for “Half-Life”

Nuclear & Particle Physics

The time required for half the radioactive nuclei in a given sample to undergo spontaneous radioactive decay.

t_½ = ln(2) / λ ≈ 0.693 / λ, N(t) = N₀ (½)^(t / t_½) Seconds, Hours, or Years

Nuclear & Particle Physics

A radiometric dating method that measures the residual decay activity of Carbon-14 in organic materials to determine their age up to…

t = -(t_½ / ln 2) ln(A(t) / A₀), t_½ = 5730 years Years Before Present (BP)

Nuclear & Particle Physics

A radioactive decay process mediated by the weak nuclear force in which a nucleus emits a beta particle (electron or positron) and a…

β⁻: n → p + e⁻ + ν̄_e; β⁺: p → n + e⁺ + ν_e MeV (Continuous Spectrum)

Nuclear & Particle Physics

The probability per unit time that an individual radioactive nucleus will undergo spontaneous nuclear decay.

λ = -(1 / N) (dN / dt) = ln(2) / t_½ s⁻¹ or years⁻¹

Nuclear & Particle Physics

A chemical compound containing a radioisotope used to trace chemical or biological pathways through living organisms or industrial systems.

A(t) = A₀ e^(-λ t) (Short half-life diagnostic radiopharmaceutical) MBq or mCi (Administered Activity)

Geophysics & Environmental Physics

The environmental migration of radioactive Radon-222 gas from decaying uranium in rocks and soil into indoor building spaces.

Decay Chain: ²³⁸U → ²²⁶Ra → ²²²Rn (Half-life = 3.82 days) Bq/m³ or pCi/L (Activity Concentration)

Results for “Half-Life”