Comment Re:Misleading title (Score 3, Informative) 91
Yeah, as usual, the summary is terrible. ALL collisions at the LHC are proton-proton collisions, not just the W-W ones.
What they're measuring is one of the higher-order corrections implied by the Higgs mechanism. Without the Higgs field, W bosons wouldn't have mass. Measuring how the Ws interact with each helps verify that the Higgs mechanism for explaining W boson mass is correct. Unfortunately, it's kinda hard to produce a W boson, much less two at once, much less getting them to interact with each other. You have to produce a lot of high-energy collisions to see it happen.
They did, and they got the answer they expected from the Higgs mechanism. Yay, Peter Higgs gets to keep his Nobel prize.