The National Physical Laboratory (NPL) has broadly the same remit and function in the UK as the National Institute for Standards and Technology (NIST) in the USA, and the Radioactivity Group (within the Acoustics and Ionising Radiation Division) is charged with generating, maintaining and disseminating standards of radioactivity in the UK – a role that has, on 2nd June 2013, recently celebrated its centenary.

Radioactivity standardisation can be considered to be one of the earliest ‘quantum’ standardisations, relying as it does only on the observation of discrete events during a defined time period in a given mass of material. In this seminar, I’ll start with on the absolute (or primary) standardisation of radioactivity, tracing it from the roots of the technique, which lie in cosmic ray measurements in the late 1920s to the mid-1930s, to current developments in this field. I’ll move on to the dissemination of such standardisation, and how these have demonstrable impact in many areas of life – especially health, worker protection and environmental monitoring. This will include some comments on future directions and challenges for radionuclide metrology laboratories.

I’ll finish with some explanation on why the NPL Radioactivity Group is keenly interested in the Atom Trap Trace Analysis (ATTA) technique – the reason for my visit to Argonne – and how this may lead us to close the circle of event observation by ultimately measuring single atoms.

Argonne Physics Division Seminar Schedule