Latest findings of the CMS and ATLAS experiments were announced in a seminar at CERN today.
- CMS results were presented by James Olsen (Princeton University, US)
- ATLAS results were presented by Marumi Kado (LAL, Paris-Saclay, France)
You can obtain copies of the presentations from this link:
ATLAS and CMS physics results from Run 2
(The ATLAS presentation PDF is very large document, save it first and then open it. It was problematic on my computer)
The most interesting finding is the bump that appeared at 750 Gev in the so-called diphoton spectrum. The bump is not statistically significant yet but there is reason to get excited because both CMS and ATLAS see a bump at the same energy range around 750 Gev. This is an unexpectedly early sign that the SM (Standard Model of Particles and Fields) is not the final theory. Particle physicists are now very optimistic that in the next 5 years the CERN LHC experiments will discover new physics beyond SM.
The bump is mysterious because there are multiple (beyond SM) model/theories that can come up with an ex-post explanation of this bump. Even if the bump becomes statistically significant in 2016 it will not be easy to decide which (beyond SM) model/theory is the right one.
“We may be seeing the radial Higgs partner predicted by little Higgs or twin Higgs models, or the dilaton arising due to spontaneous conformal symmetry breaking, or a composite state bound by new strong interactions. It could be a part of the extended Higgs sector in many different context, e.g. the heavy scalar or pseudo-scalar in the two Higgs doublet models. For more spaced out possibilities, it could be the KK graviton of the Randall-Sundrum model, or it could fit some popular supersymmetric models such as the NMSSM. ” – Resonaances
Commentary on today’s announcements
- Physicists in Europe Find Tantalizing Hints of a Mysterious New Particle (New York Times)
- New boson at 750 Gev (Resonaances)
- Matt Strassler’s comments