Synchrotron…

This entry is part 2 of 4 in the series Light

The Large Hadron Collider is not the only particle accelerator worth talking about. In fact, there is one just 30 minutes south of us. The Diamond Synchrotron uses its electron beams to produce synchrotron light which is about 1 billion times brighter than the sun. The light is produced as synchrotron radiation (wavelengths adjustable between infra-red and x-rays) when electrons are accelerated to nearly the speed of light. This can be used to examine the structure of materials at an atomic level.

Layout showing the separate beam lines.

A regular light microscope can look at objects about 0.001mm (1 µm – 1 micrometre) across using the visible wavelengths of light. This is great for looking at things like cells but no good for things that are really tiny. To look at smaller objects you need to use light at a much shorter wavelength e.g. x-rays. A synchrotron can accelerate electrons and store them in a vacuum ring until they are needed. The electrons are whizzing around the ring so fast that they could go around the world 7.5 times in one second. When the beam of electrons is deflected using powerful electromagnets the electrons emit light. This light can be sent down beamlines and focused onto whatever the scientists are studying. Each beamline represents a different set of experiments. They currently have 33 beamlines that can be used at any one time.

Uses for the synchrotron include medical research where the structure of particular proteins can be analysed leading to the development of new drugs that can interact with these proteins; analysing rocks or other materials to find out what they are made from; designing computer chips by burning the circuit structure onto tiny slivers of silicon; looking at viruses.

Scientists from the Natural History Museum are hoping to use the Diamond Synchrotron to analyse samples from the asteroid Bennu. Samples were scooped off the surface of this near-Earth asteroid by the NASA OSIRIS-REx mission. Currently (and quite amusingly I think) they can’t get the lids off the containers that hold the samples so nobody is able to analyse the contents yet. I have every sympathy as I sometimes struggle to get the lid off a jar of pickled onions.

Questions…

  1. Which has the longer wavelength, infrared light or x-rays?
  2. Which has the greater frequency, infrared light or x-rays?
  3. Diamond is one form of the non-metal element carbon. Name another form of carbon.
  4. Name another non-metal element mentioned in the text above.
  5. Electrons are negatively charged. What are the other two basic components of atoms and what are their charges?