Hints of a light stop squark at ATLAS?

Reading some rumors tonight about a 2.4 sigma excess from ATLAS in the 330-500 GeV range. This hints at a possible stop squark (the top quark superpartner) which would, if confirmed, be the first of the long awaited sparticles (long awaited by me in any case). My understanding is that ATLAS will get 4-5X more data by the end of year, so if this tantilizing excess is real, we should have better stats. 3 sigma would be a suggestion, but 5 sigma is the particle physics standard for a discovery.

Supersymmetry, or SUSY, is necessary for String Theory. The Universe can be supersymmetric without String Theory being true, but if String Theory is true, the Universe is supersymmetric. So a lot of people are hoping we find a sparticle soon.

Sparticles are the superpartners of the ‘ordinary’ Standard Model particles; the sparticles of bosons (force carriers) are fermions (matter constituents) and vice versa. The naming convention for sparticles is weird. Quarks and leptions, being fermions, will have bosonic superpartners, squarks and sleptions (the top quark’s superpartner is the stop squark, the electron has the selectron). Photons, being bosonic, will have fermionic photinos as superpartners (gluons’ superpartners are gluions, and so forth). For various reasons, the stop squark is expected to be one of the lightest sparticles, and so one of the first that accelerators can produce.

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