Higgs Discovery Update

An update on the Higgs-like resonance discovered last summer was given by the ATLAS experiment on Dec. 13, indicating that the decay to two photons is about 2 standard deviations off of the standard model value, which may indicate that there are additional new particles within reach of the Large Hadron Collider.

The largest discrepancy is in the Higgs-like boson decaying to two photons (H → γ γ).

Discovery of a Higgs-like boson

On July 4, CMS and ATLAS announced the discovery of a Higgs-like resonance. An unstable boson quickly turns into other more stable particles, in this case the clearest signal shows up in the boson decaying to two photons or four charged particles like electrons, muons, and their antiparticles. The two experiments saw a characteristic enhancement (a.k.a. a resonance or “bump”) in both of these types of decays.

An single event in the detector that may have been the two photons resulting from decay of the resonance.

The boson shows upas a bump the distribution of two photon decays.