Infographics / Nuclear Medicine

Continuous beta spectrum vs discrete gamma line spectrum

Two energy spectra side by side. Left: beta decay gives a continuous curve of particle energies rising from zero, peaking in the lower third and falling to zero at a maximum endpoint energy (Emax), with the mean energy about one third of Emax. Right: gamma emission gives a small number of discrete vertical lines at specific characteristic energies rather than a continuous distribution.

Beta decay versus gamma emission energy spectra Two energy spectra side by side. Left: beta decay gives a continuous curve of particle energies rising from zero, peaking in the lower third and falling to zero at a maximum endpoint energy (Emax), with the mean energy about one third of Emax. Right: gamma emission gives a small number of discrete vertical lines at specific characteristic energies rather than a continuous distribution. Beta decay: continuous spectrum relative number emitted beta particle energy Emax mean ≈ ⅓ Emax all energies 0 → Emax Gamma emission: discrete lines relative number emitted gamma photon energy Eγ₁ Eγ₂ a few characteristic energies (Eγ = ΔE) Beta: decay energy is shared with the antineutrino, giving a continuous spread up to Emax (mean ≈ ⅓ Emax). Gamma: transitions between discrete nuclear levels give a few line energies characteristic of the nuclide.
Practise Nuclear MedicineDownload SVG

More in Nuclear Medicine

Practice the Physics paper

FRCRX is a Part 1 Physics question bank: true/false items with explanations, timed mocks and topic analytics.

Start question practiceSee plans