Physicists working on the Large Hadron Collider at CERN have finally found the Higgs boson — the particle thought to be behind the mass of all the others. But there is still much work to be done to pin down the precise nature of the new particle. Join us at 2 p.m. BST on 5 July for a live Q&A with three CERN scientists, Matt Strassler, Seth Zenz and Zach Marshall, to find out what we still don’t know about the Higgs. Feel free to post some of your questions in advance in the comments below.