Carl K. Ross

Carl K. Ross is a physicist associated with ionizing radiation standards and water calorimetry. His 1997 paper with Norman V. Klassen identifies both authors with the ionizing-radiation standards laboratory in Ottawa and examines a fundamental problem in radiation dosimetry: deposited energy and measured heat need not be equal when irradiation also produces chemical reactions.^[ref]

Their analysis expresses the heat defect aswhere $E_a$ is absorbed energy, $E_h$ is the energy appearing as heat, $D_w$ is absorbed dose, and $c_w$ is the specific heat capacity of water. The temperature rise $\Delta T$ supplies a measurable thermal signal, while the heat defect accounts for the energy balance associated with radiolysis.^[ref]

For a hypothetical example, suppose the measured thermal quantity is $c_w\Delta T=0.98\mathrm{J}\mathrm{k}{\mathrm{g}}^{-1}$ and the heat defect is $0.02$. The corrected absorbed dose is then $0.98/(1-0.02)=1\mathrm{J}\mathrm{k}{\mathrm{g}}^{-1}=1\mathrm{Gy}$. The illustrative $2\%$ correction is chosen for arithmetic, rather than quoted as an experimental result. A positive heat defect means that some absorbed energy does not appear as heat; a negative value means that the measured heat exceeds the absorbed energy, with the difference supplied by the accompanying chemical reactions.

Ross and Norman V. Klassen later published a correction to an input reaction rate constant in their computer simulation. Their 2002 paper provides an explicit example of revising a physical measurement model when a supporting parameter changes.^[ref]