Theorists perplexed by hints of unexpected new particle
Hundreds of papers attempt explanation for surprising LHC data
![illustration of proton collision](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2016/04/042716_ec_LNC_free.jpg?fit=860%2C460&ssl=1)
NEW LIGHT A possible new particle shows up in proton collisions at the Large Hadron Collider that produce two photons, as in an event (illustrated here) seen by the CMS detector.
CMS/CERN