= Steve R. Domen
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<Steve R. Domen> developed physical <water calorimetry> methods at the <National Institute of Standards and Technology>. His 1994 sealed-water instrument measured <absorbed dose> from a minute radiation-induced <temperature> rise, while investigating how dissolved gases change the fraction of deposited <energy> that appears as heat.<A Sealed Water Calorimeter for Measuring Absorbed Dose by Steve R. Domen>[Title-page byline, abstract and section 1]{ref}
The apparatus enclosed water in a thin glass vessel immersed in a larger water tank. Two calibrated <thermistors> in glass capillaries formed part of a <Wheatstone bridge> that detected the temperature response. The vessel also limited convection. Comparing different dissolved-gas conditions tested the <heat defect>, rather than assuming that all absorbed <energy> immediately becomes heat.<A Sealed Water Calorimeter for Measuring Absorbed Dose by Steve R. Domen>[Sections 2.1–2.3, figures 1–4; abstract, approximately 3700 measurements]{ref}
For an original ideal calculation, neglect the <heat defect> and heat transfer during a reading. With water <specific heat capacity> $c_p=4180\,\mathrm{J\,kg^{-1}\,K^{-1}}$ and measured rise $\Delta T=0.240\,\mathrm{mK}$,
$$
D=c_p\Delta T=1.0032\,\mathrm{J\,kg^{-1}}=1.0032\,\mathrm{Gy}.
$$
This illustrates why sub-millikelvin thermometry matters. It is not a reported run: the real <measurement model> must include the instrument's corrections and <measurement uncertainty>.
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