Tuesday, 15 December 2015

750 GeV Diphotons

The particle physics community is currently agog with rumours about the talks later today on LHC run 2 results.  These were planned months ago, before data taking started.  In the last couple of weeks, however, there have been steadily growing reports that both experiments see a common excess: two photons with an invariant mass of 750ish GeV.  From what I hear, CMS has about 2.8 sigma and ATLAS about 3.1.  Those are local significances, but if both experiments see an excess at the same place then we don't need to worry about that.  So, it could be very exciting.

Of course, excesses have been seen before at the LHC.  I am particularly reminded of the Higgs diphoton excess that both experiments saw, that has now pretty much gone away.  An element of caution is justified.  But that won't stop a lot of people writing papers on it.  There will be papers appearing on the arXiv tomorrow, you can be certain.  Sadly I'm not in a position to get something out that early, but I do hope to be quick enough to qualify as ambulance chasing.

No comments:

Post a Comment