The AGATA-UK project has successfully delivered major upgrades to a world-leading detector, aimed at addressing fundamental questions in nuclear physics, including the origins of the elements in our Universe. This achievement was made possible by a significant STFC grant awarded to the project team, who are from STFC Daresbury Laboratory, University of Liverpool, University of York and the University of West of Scotland. 

The Advanced Gamma Tracking Array (AGATA) is a spectrometer that scientists use to study the structure of atomic nuclei in the beam. It will produce the most valuable insights yet into the structure of atomic nuclei, with potential applications in many areas, from medical imaging to monitoring the environment. 

The UK is a long-standing key member of the larger international project, involving over 40 institutions from 12 European countries, and it provides ongoing scientific and engineering support via the UK’s nuclear physics cross-community grant. However, the grant from STFC enabled the creation of a UK sub-project (AGATA-UK) to deliver several key upgrades to help further develop the ultimate gamma ray tracking spectrometer and make it a thousand times more sensitive than any previous detector system. 

​AGATA is an evolving instrument that travels to different nuclear research laboratories across Europe, enabling scientists to exploit the different beam characteristics available at each facility. Every time AGATA is dismantled and relocated, it provides a window of opportunity to rebuild the instrument with increased capacity to house more detectors and key upgrades. 

A change of site signals an opportunity for upgrades 

In 2019, the AGATA-UK collaboration was awarded £5.5 million to undertake significant work on behalf of the UK and provide several performance upgrades at its new location. Thanks to the diligent management of the project and finances by the Principal Investigator (Professor Mike Bentley from the University of York) and the Project Manager (Richard Smith from STFC Daresbury Laboratory), the AGATA-UK project not only successfully delivered all objectives within its control but also exceeded expectations by delivering eight germanium detectors, two more than originally planned. 

Four teams from the Technology Department at Daresbury Laboratory worked on the UK project for four and a half years. This work included: 

• project management 
• developing new generation electronics and detector simulation code – including testing and commissioning 
• design, installation and commissioning of the system control 
• survey and alignment services 
• mechanical design 

Daresbury Laboratory has a track record of engineering expertise – bringing decades of knowledge to the UK’s rich history of large gamma ray spectrometer design. Our team has led the mechanical design work required to locate and exploit the AGATA array at each of the major European nuclear-structure facilities to date. 

The new rotating mechanical support structure, designed and buil at Daresbury, has doubled the instrument’s detector capacity to 90 germanium detectors. Initially, the plan was to expedite the support structure to the host site in Italy for coupling with the detector array for testing and commissioning. However, due to COVID-19 restrictions, the Daresbury team was unable to travel at this critical point in the project. Consequently, the team pivoted and had the detector array shipped to the UK. 

This allowed them to test the entire assembly at on site, enabling the completion of a major milestone without delaying the overall international project. Additionally, having the complete structure at Daresbury allowed engineers to exploit the laboratory's metrology expertise and equipment to test and develop comprehensive installation and alignment procedures. This resulted in a tenfold improvement in the positional accuracy of each detector. 

Germanium detectors – an explainer 

As the name suggests, a germanium detector is used to detect. In this case, it is looking for radiation. The detector is very sensitive, and amplifies the data, which means it can be used to detect the smallest amounts of radiation in a beam. 

Germanium detectors are a useful tool for a wide variety of scientific fields: from looking at the smallest area inside the human body to the huge expanse of cosmic rays in space. 

The AGATA detector will bring equally varied benefits to the world – from monitoring radioactive waste to bomb detection and medical imaging. It has the potential to affect millions of lives. 

Not the end of the UK’s AGATA story 

Now that this project has been completed, AGATA-UK has been wrapped-up. However, that doesn't spell the end of STFC’s work on the project. 

A nuclear physics cross-community grant means that Daresbury Laboratory's nuclear physics experts continue to be involved in the ongoing experiments and further development of the instrument. 

The long-term goal for AGATA is to create a complete 360° detector and it is hoped that STFC’s experts will continue to take a lead when the next upgrade is announced. 

​Project Manager, Richard Smith, reflects:

“Thanks to the STFC grant and the excellent work of the project team, we have delivered upgrades that significantly advance AGATA, improving our chances of uncovering some of the exciting secrets of our Universe. Additionally, we demonstrated how UK expertise is supporting fundamental research on an international scale. I am very much looking forward to continuing this support, as we work towards building the next-generation AGATA with 360° detector coverage.”  

Related reading 

UK supports completion of the ultimate gamma-ray detector 

AGATA project showcase 

AGATA website​

This article was originally written and posted on STFC's LinkedIn page. ​​