Dr. Bryan Muir

Adjunct Research Professor
bryan.muir at

About Dr. Bryan Muir

The Metrology Research Centre at the National Research Council (NRC) maintains and disseminates standards of measurement – time, length, mass, temperature, etc – to Canadian organisations (e.g. industry, university, government).  The Ionizing Radiation Standards (IRS) Group at the NRC is responsible for standards of radiation absorbed dose.  My research in the IRS group involves:

1. Development of absorbed-dose standards for electron and photon beam dosimetry. The primary standard for absorbed dose in Canada is a water calorimeter and we have applied this system to photon and electron beams directly or using hybrid systems with chemical dosimeters (alanine and Fricke).

2. Investigations on the performance and calibration of linear accelerators.  At NRC, we maintain and operate three linear accelerators – a 3-40 MeV Vickers research accelerator and two Elekta clinical accelerators (one with full IGRT capability).  This work allows us to provide guidance to the clinical medical physics community in Canada.

3. Experimental measurements and Monte Carlo simulations with secondary dosimeters in megavoltage photon and electron beams, including small and non-standard beams.  A large variety of detectors (active dosimeters like ionization chambers and solid-state detectors or passive systems like radiochromic film) are available for measurements in the field and we play a role in accurate characterization of their performance. This work has led to new recommendations in international dosimetry protocols.

4. Pushing the limits of electronic portal imaging device (EPID) dosimetry.  Using these flat-panel detectors that are available on all clinical linacs, we are investigating how accurately they can be used to reconstruct dose delivered to patients either in real-time or post-treatment.  This has the potential to improve treatments by detecting errors at the time of treatment or using this “free” information for adaptive radiation therapy.

Publication list on Google Scholar:

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