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RAD-26

Absorbed dose

Gray = J/kg.

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Radiationabsorbed dose

Governing equation

D=ε/mD=\varepsilon/m

ε∈[1×10−6,1]\varepsilon \in \left[1\times 10^{-6}, 1\right]

where

\varepsilon
Energy deposited (J)
m
Mass (kg)
D
Dose (Gy)

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RAD-26 · dose
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①

Governing law — red

D=ε/mD=\varepsilon/m

ε∈[1×10−6,1]\varepsilon \in \left[1\times 10^{-6}, 1\right]

ε=1×10−6\varepsilon = 1\times 10^{-6}D=2×10−6D = 2\times 10^{-6}

②

Domain of the variable — blue

εmin⁡=1×10−6,εmax⁡=1\varepsilon_{\min} = 1\times 10^{-6},\quad \varepsilon_{\max} = 1

ε∈[1×10−6,1]\varepsilon \in \left[1\times 10^{-6}, 1\right]

ε=1×10−6\varepsilon = 1\times 10^{-6}ε=1×10−6\varepsilon = 1\times 10^{-6}

③

Response curve — green

D=ε/mD=\varepsilon/m

ε∈[1×10−6,1]\varepsilon \in \left[1\times 10^{-6}, 1\right]

ε=1×10−6\varepsilon = 1\times 10^{-6}D=2×10−6D = 2\times 10^{-6}

④

Rate of change — amber

dDdε\frac{\mathrm{d}D}{\mathrm{d}\varepsilon}

ε∈[1×10−6,1]\varepsilon \in \left[1\times 10^{-6}, 1\right]

ε=0.006\varepsilon = 0.006D′=2D^{\prime} = 2

Lecture brief

Historical brief

Beer attenuation, Compton (1923), Klein–Nishina, Bragg–Gray cavity and KERMA are the transport of photons and charged particles in matter. The sheets compute fluence, kerma and stopping. This sheet (RAD-26 — Absorbed dose) is the form associated with absorbed dose. Working symbols: ε\varepsilon, mm →\rightarrow DD. Gray = J/kg.

Purpose

Purpose: compute DD from ε\varepsilon, mm in Radiation physics via D=ε/mD=\varepsilon/m Gray = J/kg. Use it when a real radiation physics question must be answered in SI before a code check.

Live realistic example

In symbols

Live case. Given ε=0.010 J\varepsilon = 0.010\,\mathrm{J}, m=0.500 kgm = 0.500\,\mathrm{kg}, the governing relation D=ε/mD=\varepsilon/m yields D=0.020000 GyD = 0.020000\,\mathrm{Gy}. Gray = J/kg. Move a slider: the numbers are this situation, not a canned story.

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Inputs

Outputs

  • Dose D0.020000 Gy
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RAD-26 · dose
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Narration of this film

Gray = J/kg.

Gray = J/kg.

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