Curtain closing on Higgs boson photon soap opera

日期:2019-03-05 04:17:02 作者:向硇 阅读:

IT WAS the gripping soap opera of particle physics, but the first season ends in an anticlimax. The Higgs boson’s decay into pairs of photons – the strongest but most confusing clue to the particle’s existence – is looking utterly normal after all. Experiments infer the Higgs boson’s existence by looking at the particles left behind when it decays. One way it made itself known two years ago at CERN’s Large Hadron Collider (LHC) near Geneva, Switzerland, was by decaying into pairs of photons. In fact, it decayed so prolifically that physicists considered it a “deviant decay” – a possible window into exciting new physics. But over the past year, physicists at CERN have found that the Higgs boson is acting exactly as the still-incomplete standard model of particle physics predicts, leaving us with no clues about how to extend the model. Now, in an anticlimactic summary on the two-photon decay, both big experiments at the LHC have posted results confirming that the photons are, despite much hope, doing exactly what the standard model predicts. “This is probably the final word,” wrote CERN physicist Adam Falkowski on his blog, Resonaances. But CERN physicist Albert de Roeck, ever the optimist, thinks there is still room for two-photon decay to be caught misbehaving once the LHC switches back on next year at double its previous energy. “I still believe ultimately we will find significant deviations or something unexpected,