Gamma Ray Camera Will Give New Insights into Stars

A major step forward in our understanding of the structure and behavior of some of the most elusive atomic nuclei in existence, some of which occur only briefly on the surface of exploding stars, is now taking place thanks to the first experiments to come from the new Advanced Gamma Tracking Array (AGATA).

AGATA has been developed by the STFC’s Nuclear Physics Group, and a group of UK universities funded by STFC, with the aim of studying the very rarest and heaviest elements predicted to exist. This is research that could answer some of the most fundamental questions about our universe. AGATA is currently based at the GSI Helmholtz Center for Heavy Ion Research in Darmstadt, Germany.

A thousand times more sensitive than any previous detector built, and with an unparalleled level of sensitivity to electromagnetic radiation, AGATA will, at final set up, be able to observe the structure and interior of these rare and exotic nuclei by measuring the gamma rays they emit as they decay. The exciting potential of this spectrometer led to the creation of the international AGATA collaboration of 12 European counties involving 40 institutions.

Professor John Simpson, Head of STFC’s Nuclear Physics Group and International AGATA spokesperson, said: “Nuclear physicists look to create and study the very rarest and heaviest elements predicted to exist, so it is really exciting to see technology developed by the STFC’s Nuclear Physics Group, and UK universities, contribute to this research that could answer some of the most fundamental questions about our universe. It also shows the importance of UK nuclear physicists playing leading roles in both the science program and development of advanced detection systems at world leading laboratories such as GSI. Now that the first set of experiments has been completed at AGATA, we are really looking forward to hearing the results once the data has been analyzed.”

Atomic nuclei make up most of the visible matter in the universe. Exotic nuclei, such as those produced by fusion in stars, are so unstable that they might only exist for a matter of seconds before they destruct and produce the stable matter from which we are made. By understanding the structure of these unstable, exotic nuclei we may reveal why some are more stable than others, or have particular shapes, leading to deeper insights into how stars are born and evolve.

STFC’s scientists, along with other key partners from the Universities of Liverpool, Manchester, Surrey, West of Scotland and York, have taken a leading role in AGATA’s development, particularly in the engineering and electronics design. The mechanical structure was delivered by the UK to GSI early in 2012, and experiments started in September after an intense period of installation and commissioning.

One of AGATA’s first experiments, co-led by the University of Surrey’s Zsolt Podolyak, was to observe the extremely rare and neutron rich variants of mercury and platinum nuclei, and specifically investigate how protons and neutrons in these nuclei behave collectively. This will lead to a better understanding of the synthesis of the heavy elements in stars, specifically in supernovas and neutron star mergers.

This research paves the way for further UK science programs at the future international FAIR accelerator (Facility for Antiproton and Ion Research) at GSI, where the UK will play a significant role in this growing area of atomic science through a collaboration called NuSTAR (Nuclear Structure, Astrophysics and Reactions).

Contact:
Wendy Ellison
STFC Press Officer
+44 (0)7919 548012
wendy.ellison@stfc.ac.uk

The Science and Technology Facilities Council is keeping the UK at the forefront of international science and tackling some of the most significant challenges facing society such as meeting our future energy needs, monitoring and understanding climate change, and global security.

The Council has a broad science portfolio and works with the academic and industrial communities to share its expertise in materials science, space and ground-based astronomy technologies, laser science, microelectronics, wafer scale manufacturing, particle and nuclear physics, alternative energy production, radio communications and radar.

STFC operates or hosts world class experimental facilities including:

* in the UK; ISIS pulsed neutron source, the Central Laser Facility, and LOFAR. STFC is also the majority shareholder in Diamond Light Source Ltd.

* overseas; telescopes on La Palma and Hawaii.

It enables UK researchers to access leading international science facilities by funding membership of international bodies including European Laboratory for Particle Physics (CERN), the Institut Laue Langevin (ILL), European Synchrotron Radiation Facility (ESRF) and the European Southern Observatory (ESO). STFC is one of seven publicly-funded research councils. It is an independent, non-departmental public body of the Department for Business, Innovation and Skills (BIS).