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Saskatoon — The switch was officially flipped on one of the largest science projects in Canadian history Friday, igniting the passions of researchers who aim to do everything from creating smaller radios to curing the common cold.

Saskatchewan Premier Lorne Calvert and federal Finance Minister Ralph Goodale joined scientists from across the country in turning on the massive $173.5-million Canadian Light Source synchrotron — a winding concoction of pipes and wires, housed in a facility the size of a football field at the University of Saskatchewan.

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People have been excited about this for quite some time, since tightly focussed X-rays and gamma rays can probe substances very well and give a very good picture of what they look like.

Originally, synchrotron radiation was known to be an artifact of the way cyclotrons and their modern cousins, synchrotrons, work: since they make particles move faster by accelerating the particles not in a straight line, but in circular paths, the particles, in doing so, emit Bremsstrahlung ("braking radiation").

This is essentially a loss of kinetic energy in the form of X-rays or gamma rays and as such for particle accelerator facilities that want high-energy particles the Bremsstrahlung so emitted is a nuisance, since it means the magnets have to be overdesigned to compensate for this, and the electric fields have to be made more powerful, and so on. (A related form of Bremsstrahlung is the characteristic high-intensity, low-energy radiation emitted by pure beta emitters like Phosphorus-32; the electrons emitted from the radioactive nuclei are strongly affected by nearby positive nuclei, and so they give off X-rays as they are deflected.)

For the light source, such as the one in Saskatchewan, it is desired to have a lot of Bremsstrahlung, so the loss of energy is not a factor; its intensity and energy is the primary concern.

[ 23 October 2004: Message edited by: DrConway ]

The article says Synchrotrons have been in use for 30 years, and they are all over the world, with Canada being the last of the developed nations to get one. If this is the case, and considering all the money we spend world wide on cancer and disease research, why have they not found the chemical messenger locks for these things already?

Of course, I understand that every virus is genetically different from its precursor. And cataloguing locks for them all for everything and everyone is impossible. It would have to be done on a individual basis. However, this is not the case for bacteria per se. Why has it not been done for serious and death threatening strains over the last 30 years? Instead of broad spectrum anti-biotics, which have now left us with super strains, we could have had targeted locks.

The light source in Saskatchewan could be pressed into service as an electron accelerator by taking two electron beams and smashing them into each other to see what sprays off, so to speak, or to take one beam and aim it at a target.

(Edit for embarassing braino. )

[ 23 October 2004: Message edited by: DrConway ]

Another use of high-energy electrons would be to do scattering experiments on nuclei to see how they "appear" when probed using the electromagnetic interaction.

(It turns out, incidentally, from previous experiments, that nuclei do seem to have different radii when you probe them electromagnetically than when you probe them "strongly" - i.e. with neutron scattering experiments)