Heather on her visit to OPAL. The steel cage that is intended to protect the reactor from aircraft impacts, is visible in the background.

Credit: Katynna Gill

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I was trying to get to the heart of neutron science and that meant travelling to the site of Australia's newest and most technologically advanced nuclear research reactor. But like the tricks of a stage magician, I found that sometimes fission can be as hard to see as it is to understand.

Nuclear technology is firmly entrenched in intriguing controversy. But on my first visit to the reactor, I found myself drawn towards the mystery of fission for its own sake.

I'd spent weeks researching everything nuclear for a 16-page supplement in the latest print edition of Cosmos magazine, and now I was driving 50 km across Sydney in the rain and it was making me feel a little edgy. I was crossing the city from the northern suburbs to Lucas Heights, a comfortable scenic expanse in the far south, and home of the Australian Nuclear Science and Technology Organisation (ANSTO).

The visit – to tour ANSTO's new reactor, OPAL - felt a little like coming face to face with someone I'd met remotely over the Internet. The trip was the culmination of six weeks research into nuclear research reactors – what they did (create radioisotopes for diagnosing and treating cancer and components for semiconductors) and what they had the potential to do (understand the structure and nuances of an astounding range of materials in great detail).

Shiny silver pipes

Media interest was building about the opening of OPAL, the replacement of 1950s reactor HIFAR (High Flux Australian Reactor), described by some scientists as a Model T to OPAL's Porsche.

For the last six weeks I had eaten, slept and breathed nuclear science as I attempted to grasp for Cosmos how this A$360 million nuclear reactor worked, as well as everything associated with building a reactor in Australia.

I had many questions. How does the reactor - touted as one of the top three research reactors in the world - affect Australian science? Why are we making radioactive isotopes and carting them across the country? What does the world think of OPAL? And what are those several pieces of technology attached to shiny silver pipes which feed out of the nuclear reactor's core (such as the 'high-resolution powder diffractometer', or the 'thermal 3-axis spectrometer')?

More than anything, I was looking forward to seeing radiation. I'd discovered that once the magic of fission begins, the core is suffused in the eerie blue glow of Cherenkov radiation. This is a side-effect of charged particles passing through an insulator - in this case demineralised water - at speeds faster than the speed of light in that medium.

It sounds like science fiction, which is why I was looking forward to seeing it.

Kick-starting fission

Fission in a reactor core is kick-started by dropping a radioactive element into the core - a box full of aluminium-clad uranium 235 fuel rods - causing the uranium atoms to split and release neutrons. Neutrons are the mass-bearing, chargeless associates of protons within the atomic nucleus.

Once the neutrons are liberated they can be directed along the mirrored surfaces of long tubes called neutron guides. Here they are subjected to a range of adjustments, such as being cooled to about -250°C, being slowed, or being fed into 'neutron scattering' instruments.

These instruments were causing a buzz locally and internationally. I'd heard how they could be used to understand a whole range of questions, from building better hydrogen fuel cells to understanding protein interactions. These in turn, could redefine the way we understand disease pathogens such as the AIDS virus or the bacteria responsible for Legionnaire's disease and meningitis. I'd also heard neutron scattering techniques described as a "fast track" to Nobel Prize-winning science.

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