UK boffins sniff for Higgs boson
Large Hadron Collider hits CERN
Particle physicists in the UK have finished building a key component of ATLAS, one of the four major experiments that will run on the Large Hadron Collider (LHC) at CERN.
The kit in question is the first barrel of a semi conductor tracker, or SCT, and it is the eyes of the ATLAS experiment. The Large Hadron Collider will recreate the conditions that existed mere moments after the big bang. ATLAS is designed to see what happens next.
The LHC will accelerate two proton beams, directed at each other, to energies seven times higher than have been achieved so far. When these beams meet head on, they will create a new generation of particles, which in turn bump into each other. The SCT will track and measure the momentum and direction of charged particles spinning off from these collisions. The scientists hope the resulting data will help them understand how and why the universe is the way it is.
Dr Tony Weidberg from the University of Oxford explains: "The SCT will track charged particles as they move through silicon wafers to an accuracy of better than 20 microns - that's less than the diameter of a human hair - over the diameter of 1 metre. This will allow us to calculate their momentum, providing part of the picture of what happens when protons are collided at high energy."
Other parts of the detector will pick up different particle properties, allowing the scientists to reconstruct the collisions, much like accident investigators would do after a car crash.
Particle physicists get very excitable about this project because of the fundamental questions they're hoping to answer. ATLAS will be involved in the hunt for the Higgs boson, a theoretical particle currently used to explain why matter has mass.
Dr. Weidberg goes on: "There are very strong indications that the exploration of this completely new energy regime will lead to the discovery of new physics, such as Supersymmetry which would imply the existence of exotic partners to all the previously discovered particles. The new physics might be even more exotic and involve extra spatial dimensions and the production of mini black holes." ®
We are far from experts in this area, so we'll leave a description of the device to the Particle Physics and Astronomy Research Council:
The entire SCT detector consists of 60 square metres of silicon detectors in the form of four concentric barrels and two end-caps. The first completed barrel has been populated with 384 silicon modules and each of the three outer barrels will carry progressively more modules with the fourth and final barrel having 672 silicon modules. The SCT overall is divided into 6 million channels and every channel has its own amplifier and data buffer. All four barrels of the SCT will be assembled in the UK using components from a world-wide collaboration of 37 Institutes.