Particle discovery – is it really the Higgs?

Cern scientists working at the LHC (Large Hadron Collider) have discovered a new particle which is consistent with the long-sought Higgs boson. More investigations are, however, required before it can be confirmed that the particle truly is the Higgs.

Cern scientists working at the LHC (Large Hadron Collider) have discovered a new particle which is consistent with the long-sought Higgs boson.

– The discovery is a major breakthrough in particle physics, says Professor Paula Eerola from the Department of Physics at the University of Helsinki. Eerola heads the three Finnish research groups from the Helsinki Institute of Physics, the University of Helsinki and the Lappeenranta University of Technology taking part in the Cern CMS experiments.

Named after the British physicist Peter Higgs, the Higgs boson is the last missing element in the Standard Model in physics, which could explain how the other particles attain their mass.

– The Higgs boson has been hunted for nearly fifty years, says scientist Lauri Wendland from the Helsinki Institute of Physics.

Higgs boson has been searched for with the LHC. It collides protons with a great amount of energy, generating various elementary particles. The energy and intensity of the LHC should be sufficient to produce the Higgs boson, provided it exists. The Higgs boson decays so rapidly that it can only be detected indirectly, once it has transformed into other more stable particles.

The CMS experiments carried out with the LHC have now revealed a new particle weighing in at 125GeV. The confidence level of the discovery is five sigma.

– This means we are 99.99996 per cent certain that this result is not a coincidence and that we have observed a real particle, says Lauri Wendland.

The confidence level was further bolstered by LHC’s Atlas experiments, the results of which were published today and were in line with the CMS results.

The new particle is consistent with the hypothesised Higgs boson. More data is required, however, before scientists can be certain that the particle really is the Higgs boson.

– Determining the qualities of a new particle is a slow process, says Paula Eerola. However, the clear consistency with the Higgs boson gives direction to further research.

University of Helsinki Department of Physics »»

The Helsinki Institute of Physics (HIP) »»

Higgs hunters’ blog »»

CMS results »»

Paula Eerola in the Tuhat research database »»

Comment on Facebook »»

Text: Katja Bargum
Photo: CERN
9.7.2012
Translation: AAC Global
University of Helsinki, digital communications


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