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Record breaking accelerator
By Hamish Johnston in Portland, Oregon
Here’s a question for you, what is the most powerful accelerator in the world?
No, it’s not the LHC – that holds the record for energy – the answer is the Spallation Neutron Source (SNS) at the Oak National Lab in Tennessee.
In September 2009 the facility delivered a pulsed beam of 1 GeV protons at a power of 1 MW.
The pulses are fired at a target of liquid mercury, creating copious amounts of neutrons, which can then be slowed down and used for studying solids and liquids.
This afternoon I saw a nice talk by Stuart Henderson of Oak Ridge about recent progress at the SNS. Since experiments began in 2006, the number of instruments attached to the neutron beamline has grown to 12 and he expects that 16 instruments will be running by 2012.
And of course, Oak Ridge hope to upgrade the facility between 2012–2017 – boosting the energy to 1.3 GeV and the power to 3 MW.
No, it’s not the SNS. The answer is the Paul Scherrer Institute’s High Intensity Proton Accelerator facility. Since May 2009 the PSI-Ring cyclotron delivers a proton beam of 590 MeV at a current of 2.2 mA. This corresponds to a beam power of approximately 1.3 MW. The beam is not pulsed (though has a 50 MHz time structure) and is fired through two carbon targets for meson production and finally ends up in the SINQ-target where neutrons are produced. The machine runs 24 h a day and 200 days a year with an average availability of 90%.
Furthermore, PSI follows an upgrade path to reach 3 mA in CW-mode within the next 10 years. So up to now this facility holds the world record in beam power.
We at LANSCE applaud the remarkable achievements of SNS and PSI in high power accelerator development.
It is nice to see these facilities join the 1MW club, inaugurated by the LANSCE accelerator in 1986. Then called LAMPF, LANSCE reached 1.2mA at 800MeV proton energy–1 MW–and ran at that power routinely until ca. 1999. (For budget reasons, LANSCE runs at lower power now.) Like SNS, LANSCE is pulsed, which provides high peak power for time of flight techiques.