CERN Accelerating science

Read the paper: TOP-11-003

The measured production rates of Top-antiTop pairs, where one lepton and four jets of particles is observed in the final state, show good agreement with Quantum Chromodynamics (QCD), the theory of the strong interaction.

The number of events that an experiment observes is proportional to a quantity called the luminosity — a measure of how many collisions are occurring in the detector.

This year's HCAL test beam run in July was completely devoted to studies of hardware that will be used in the upcoming upgrades. During the course of the two weeks the detector was moved in two independent setups – HF and the combined EB+HB+HO – into various positions relative to the beam.

High-energy collisions with final states that include leptons (electrons, muons or taus) have played major roles in the history of physics. Several particles – such as J/ψ, W, and Z – as well as productions of pairs of Top quarks were discovered in their leptonic decay modes.

CMS published its 100^th paper on 3^rd August. This accomplishment, unprecedented in its pace, came as a result of many things working together extremely well.

Once more a reminder of the Lepton-Photon approvals, which will start in less than a week from now.

CERN, focus of research into the Big Bang and what makes the universe tick, on Thursday announced a new program -- fusing science with art to encourage painting and music inspired by the wonders of the cosmos.

Read the paper: QCD-10-037

This paper extends CMS’s previous measurements of the production rates of isolated prompt photons. The production rates agree with the predictions of perturbative Quantum Chromodynamics (pQCD), although, at low transverse energies, the predictions tend to be higher than the measured values.

The current data from the LHC show an effect which might, or might not, be the first indication of the presence of a Higgs boson. Most of this effect is due to the number of pairs of W bosons which are being produced in proton-proton collisions.