What is a synchrotron? A particle accelerator that produces very bright beams of light: infrared, visible, UV and X-rays

The Australia Synchrotron in Melbourne Circumference = 216 mCost = $206 million

European Synchrotron in Grenoble, France one of world’s largest at ~2km circumference

What is it?

Storage ringANKA, Germany

What does it look like inside?

How does it work?

Bending magnetapprox 7.5 tonnes

Creating the light

How does it work?

When charged particles such as electrons accelerate they emit electromagnetic waves.

Electrons are generated here

and initially accelerated in the linear accelerator

(LINAC)

How does it work?

They then pass into the inner booster ring where they are accelerated to 99.9997% of

the speed of light.

How does it work?

How does it work?

From the booster ring they are transferred into the storage ring.

Finally they reach the storage ring.

How does it work?

Bending magnet - sweeping searchlightAt each deflection of the electron path a beam of radiation is produced.

Types of light sources

Insertion devices - produce higher intensity

WigglerBeams emitted at each pole reinforce each other and appear as a broad beam of incoherent light.

UndulatorProduces a very narrow beam of coherent light, amplified by up to 104

How does it work?

How does it work?

How does it work?

How does it work?

How does it work?

Why is wavelength important?

Why is it special?

Visible light X-rays

To penetrate a sample, you need a wavelength of similar, or smaller magnitude.

sample sample

1. Brilliant - many orders of magnitude brighter than conventional sources, enabling quick experiments on small samples.

Properties of synchrotron light

Properties

2. Continuous spectrum - from infrared to hard X-rays

Properties

Why does Australia need a $206 million synchrotron?

The 1200+ scientists who use the Australian synchrotron will make many discoveries. The importance of many of these discoveries will probably only become apparent many years into the future.

When Faraday discovered a method to generate electricity with magnets he was asked ‘what use does it have’, to which he responded, ‘what use is a new born baby?’

This is true of many of the discoveries that will be made with synchrotrons: their importance will only be apparent many years into the future.

Photo: courtesy AIP Emilio Segrè Visual Archives

Summary

Further reading and resourcesAn excellent animation showing the production of x-rays in a synchrotron can be viewed atwww.isa.au.dk/animations/Finalmovie/astrid_ total_ v2.mov

The State Government of Victoria has further background material www.synchrotron.vic.gov.au

The Canadian Synchrotron website has further resourceswww.lightsource.ca

UWA scientist Dr Peter Hammond has a site on synchrotrons that can be viewed at http://internal.physics.uwa.edu.au/~hammond/SyncRes/