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Nuclear Physics

Lund University

Biosheric and Anthropogenic Radioactivity (the BAR group)

The BAR group works with measurement of man-made radionuclides which can be found in the environment. We use decay measurements (liquid scintillation counting) as well as mass spectrometric methods (accelerator mass spectrometry, AMS). The nuclides we focus on are mainly 14C and tritium (3H, or super-heavy hydrogen).

The Accelerator Mass Spectrometry (AMS) technique actually counts single atoms! It’s most well-known application is radiocarbon (14C) dating, that can determine the age of geological and archaeological objects of ages up to 50 000 years.

Lund University has worked with AMS since the beginning of the 1990ies. In 2004, the large AMS machine at the Physics Department was replaced by a small and modern AMS machine (SSAMS), devoted to 14C measurements. This facility is located at the GeoBio Centre, where also the Radiocarbon dating laboratory is located.

The 14C-AMS group at the Nuclear Physics Division has since the beginning of the 1990ies used AMS in a variety of scientific fields. Examples are studies of releases of radioactive elements from nuclear power plants, the use of radioactive substances in medicine and development of new pharmaceuticals.

Presently, our research partly focuses on so called bomb pulse dating. This technique uses 14C produced in atmospheric nuclear weapons tests in the mid 1900s as a tracer to obtain valuable information, for example on how fast different deceases develop in the human body.

Another part of the research group use 14C as a tool to understand how human activities, that generate small particles (aerosols), affect Earth’s climate.

Within a few years, the most powerful spallation source in the world, the European Spallation Source (ESS), will be put in operation in Lund. The BAR group and scientists from Medical Radiation Physics in Malmö  are involved in a collaboration agreement with ESS, entitled “Monitoring of environmental radioactivity and radiation levels for ”Zero Point” assessment and contributions to ESS environmental monitoring plan”. One aim is to establish the current levels of ionizing radiation and concentration of various radionuclides in the surroundings of ESS prior to start of operation of the facility. This is done in order to ensure that the ESS complies with the requirements of the Radiation Protection Authority in the future.