Investigate how technological developments have enhanced scientific research, including a research facility such as a nuclear reactor or synchrotron

What this dot point is asking

NESA wants you to describe how a large-scale research facility enables scientific research that would otherwise be impossible, with a specific case study. The OPAL reactor at ANSTO is the recommended Australian example.

The answer

OPAL (Open Pool Australian Lightwater reactor) is Australia's national nuclear research reactor. Operated by ANSTO at Lucas Heights in southern Sydney since 2007, it produces nuclear medicine isotopes and provides neutron beams for materials research.

What OPAL is

OPAL is a 20 MW reactor that uses low-enriched uranium fuel (less than 20 per cent U-235, well below weapons-grade) cooled by light water. It replaced the older HIFAR reactor in 2007 and is one of about 50 research reactors operating worldwide. Importantly, OPAL is not a power reactor: it does not generate electricity. Its purpose is to produce neutrons.

What neutrons can do

Neutrons are neutral subatomic particles produced in the reactor's core. Two main uses:

1. Probing materials with neutron beams.

Unlike X-rays, neutrons pass through dense materials, are scattered by light elements like hydrogen and reveal atomic positions, magnetic moments and atomic vibrations. Eight neutron-beam instruments at OPAL serve fields from drug design to battery research.

Specific instruments at OPAL include:

• WOMBAT. A high-intensity diffractometer for fast atomic structure determination.
• KOWARI. A residual stress diffractometer used for engineering components and welds.
• PELICAN. Time-of-flight spectrometer for dynamics of magnetic and quantum materials.
• PLATYPUS. Reflectometer for thin films and interfaces.

2. Transmuting targets to produce radioisotopes.

Materials placed in the reactor are bombarded with neutrons, which converts stable isotopes into useful radioisotopes.

Nuclear medicine production

OPAL is the only Australian source of medical radioisotopes.

Technetium-99m alone is used in 80 per cent of all nuclear medicine procedures globally. About 700,000 scans per year in Australia depend on OPAL.

Other applications

Silicon transmutation doping

Pure silicon ingots are irradiated to convert a small fraction to phosphorus, producing semiconductor-grade silicon used in high-voltage electronics for solar arrays and electric vehicles. OPAL is one of the world's largest commercial doping services.

Neutron activation analysis

Trace elements can be detected at parts-per-billion sensitivity by activating samples and measuring the gamma rays emitted. Used for forensic science, archaeology and environmental monitoring.

Indigenous artefact analysis

Researchers have used OPAL's neutron techniques to study Aboriginal ochre samples and stone tools, identifying trade routes and pigment sources across the continent.

Scientific output

About 700 visiting scientists from Australian and international universities use OPAL's beam instruments each year. Output includes:

• Lithium-ion battery materials. Neutron diffraction of cathode materials at the University of Wollongong and ARC Centres of Excellence.
• Mining waste characterisation. Neutron techniques for tracking heavy-metal contamination.
• Pharmaceutical research. Drug crystal structure determination.
• Climate science. Ice-core dating using neutron activation.

Strategic and policy context

ANSTO's OPAL gives Australia:

• Independence from overseas supply of molybdenum-99. The Canadian NRU reactor (a major global supplier) shut down in 2018, causing global shortages. OPAL has helped stabilise supply.
• A neutron-science capability that universities cannot afford to build individually.
• A national nuclear science training facility.

Controversies

• Safety. OPAL is licensed by the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) and operates to international Atomic Energy Agency (IAEA) safeguards.
• Waste. Spent fuel is sent to France for reprocessing under a long-term agreement; intermediate-level waste remains at Lucas Heights pending a National Radioactive Waste Management Facility, which has been politically contested.
• Cost. OPAL cost approximately 400 million AUD to build, and ANSTO's annual budget is around 250 million AUD per year. Critics argue the cost is high relative to other research-funding options; supporters cite the irreplaceable medical isotope supply.