Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

A Transfer-Function Approach to Characterizing Heat Transport in Water Calorimeters Used in Radiation Dosimetry



Ronald E. Tosh, Huaiyu H. Chen-Mayer


The calibration chain for medical radiotherapy beams requires a primary reference standard that defines the quantity of absorbed dose to water. Water calorimetry is the most direct technique for such measurements; however, its susceptibility to systematic errors due to conduction and convection effects within the water has slowed its adoption by the international metrology community. The usual practice for correcting such errors involves finite-element simulations to estimate the step response of a given calorimeter to sequences of radiation exposure; as such, these corrections depend upon the exposure timing and must be recalculated when conditions change. We have developed an alternative approach in which calorimeter response is characterized in the frequency domain as a transfer function containing thermal properties as parameters. This approach offers useful insights for optimizing the signal-to-noise ratio and eliminating systematic errors, and, when applied to simulated data, produces a transfer function that characterizes the experimental data.
Proceedings Title
Proceedings of ITCC29/ITES17 Conference
Conference Dates
June 1, 2007
Conference Title


effects of conduction and convection, frequency domain analysis, transfer function, water calorimetry


Tosh, R. and Chen-Mayer, H. (2007), A Transfer-Function Approach to Characterizing Heat Transport in Water Calorimeters Used in Radiation Dosimetry, Proceedings of ITCC29/ITES17 Conference (Accessed July 14, 2024)


If you have any questions about this publication or are having problems accessing it, please contact

Created June 1, 2007, Updated June 13, 2017