21 December 2009

LHC ready to hunt for Higgs

”It has gone quickly creating collisions in the large particle accelerator, LHC at CERN, and the results are simply fantastic”, says a very happy physicist at the Niels Bohr Institute, Troels Petersen, though he is somewhat bleary-eyed from  sitting almost around the clock analysing data from the ATLAS-detector.

On the 23rd of November the accelerator started to send protons around the 27 km long particle accelerator and since then it has gone quickly creating collisions with energies up to 2.35 TeV. In the beginning the ATLAS-experiment had 211 collisions, then it was 8,000, then it was a 5-digit figure, a few days later it was in the 6-digits and now they are up to several million.

”It is almost like an advent calendar, where the gifts get bigger and bigger”, says Troels Petersen. The data the researchers are analysing from the collisions do not provide new information about physics, but about the detector itself.

The detector is not only working as it should, but better than the researchers had dared to hope. 

”We are very positively surprised over how well the detector works and how quickly we can get the results and how high quality they are”, explains Troels Petersen.

The LHC has stopped with collisions for this year and plan to start up again in February. It will be at even higher energies than the 2.36 TeV, which is already a world record. CERN is now preparing for collisions at 7 TeV and with that will be ready to search for the Higgs particle, dark matter and black holes. The Higgs particle is the elementary particle, which in theory gives mass to all matter, but it has not been possible to observe this particle. With the experiments at LHC it is hoped that they can determine whether it exists and how heavy it is.

The researchers expect that a Higgs particle will be formed in one out of every 1,000 billion collisions at those energies that the LHC should be up to next year. ”If the Higgs is there, then we will find it”, explains a very optimistic Troels Petersen.