Wednesday, March 20, 2013

The Mysterious Higgs Boson


The Higgs boson will not open the door to exotic new physics anytime soon. The last remaining quirk in the particle's known properties has vanished from the data of one of the two experiments responsible for detecting the boson.

The Large Hadron Collider at CERN near Geneva, Switzerland, doesn't see the Higgs directly, but instead looks for the slew of particles it decays into. Back in July, when the ATLAS and CMS experiments, both at the LHC, announced the particle's discovery, they reported a number of anomalies, including almost twice as many pairs of photons among the decay debris as is predicted by the standard model of particle physics.

Since the standard model still can't explain everything, including dark matter and gravity, many hoped these anomalies would provide a clue as to how to extend the model.

But, as more LHC data has accumulated, the quirks have vanished, leaving only the photon excess. Now even this looks unlikely to stick around. Last week, ATLAS published its most recent analysis, which failed to shed light on whether the excess was real or not.

CMS, meanwhile, has remained silent on the matter since July – though a rumour that surfaced on Twitter last week suggested that the experiment's excess of photons, also referred to as gamma rays, might have decreased, bringing it closer to the predictions of the standard model.

Read it all here.


No comments: