The LHC shows the way

For reasons too complicated to explain, I am at The LHC Show the Way workshop at the Aspen Center for Physics.

This is a three week workshop on the latest results from the LHC, to be followed by a four week workshop on new physics from the LHC and possible connections to dark matter.

The kickoff presentation is on the current status of the experimental results. Relayed from the ICHEP meeting.
Just for fun I'll do some liveblogging from the somewhat outside perspective of an astrophysicist.

The current run at the LHC will be extended to Dec 17, couple months beyond planned before going into a ~ 18 month extended planned shutdown for an upgrade to higher energies. If all goes well, this would deliver two orders of magnitude increase in collision cross-section, and maybe an order of magnitude increase in the statistical confidence of detection of the Higgs, and, more importantly, the branching ratios of its decay modes.

Current data, solving for 125 GeV Higgs mass, still shows γγ decay modes high, and the ττ mode still looks a little low, but neither discrepancy is formally statistically significant.

Lots of tweaks and improvements in signal extraction and resolution since last formal announcement, and energy has gone up to 8 TeV.

Curiously most of the deviation from the standard model branch ratios is coming from the CMS detector, ATLAS looks almost perfectly in line with the standard model.

Future attractions: H -> ZZ decay would show Higgs parity from the angular distribution of the decay products of the Z (4 lepton decay)

Lots of Monte Carlo sims for what might be possible to see at the higher cumulated cross-section, IF there is something new to see.

Second session: looking for supersymmetry signatures through dilepton decays.
Same sign dileptons, as opposed to opposite sign dileptons.
All data to date consistent with standard model.
No signs of supersymmetry.
No sign in other channels either, and those are messier.

Implies fermionic supersymmetric particles must come in at ~> 700 GeV or so.
Could still have a light supersymmetric partner to the top quark - the stop.

A "natural" supersymmetric theories need a light stop at this point to be viable.

Would make for an interesting possible dark matter candidate.


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