= Carl K. Ross
{c}
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>.<Water Calorimetry: The Heat Defect by Norman V. Klassen and Carl K. Ross>[Printed p.63, byline, affiliation, Abstract and Introduction]{ref}
Their analysis expresses the <heat defect> as
$$
k_{\rm HD}=\frac{E_a-E_h}{E_a},
\qquad
D_w=\frac{c_w\Delta T}{1-k_{\rm HD}},
$$
where $E_a$ 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>.<Water Calorimetry: The Heat Defect by Norman V. Klassen and Carl K. Ross>[Printed p.63, Eqs1–2 and following explanation]{ref}
For a hypothetical example, suppose the measured thermal quantity is $c_w\Delta T=0.98\,\mathrm{J\,kg^{-1}}$ and the <heat defect> is $0.02$. The corrected <absorbed dose> is then $0.98/(1-0.02)=1\,\mathrm{J\,kg^{-1}}=1\,\mathrm{Gy}$. 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.<Water Calorimetry: A Correction to the Heat Defect Calculations by Norman V. Klassen and Carl K. Ross>[Printed p.171, Abstract: replacement of model III by model IIIR]{ref}
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