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.

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.

This is a well-written piece exploring the need for more data and what possible interpretations there could be: http://www.guardian.co.uk/science/life-and-physics/2011/aug/06/1

Please try out the completely new CMS Web site: http://cmsexperiment.web.cern.ch.

Leave comments by clicking the "GIVE FEEDBACK" link on the side of the page, or contact Lucas Taylor.

Building 40 at CERN’s Meyrin site was abuzz with excitement as CMS formally inaugurated an art installation featuring a full-size high-resolution photograph of the CMS detector organised by the CMS Communications Group.

Read the paper: QCD-10-037

The measured Drell-Yan production rates, normalised to the production rates in the Z-boson region, show good agreement with the theoretical predictions.

Read the paper: BPH-11-002

The observed numbers of events in both decay modes are consistent with those expected in the Standard Model.
Upper limits on the branching fraction have been determined at 90% and 95% confidence levels (CL).

The CMS collaboration is presenting its latest results this week at the 2011 Europhysics Conference on High-Energy Physics, held in Grenoble, France.

Building 40 at CERN is going to change its appearance. A beautiful 1:1 maxi-poster of CMS is being installed in the central hall. To celebrate the completion of this installation we would like to invite you to a short drink this coming Friday from 12 to 1PM.

CMS is now running with 1236 bunches of protons !

This year's LHC physics run started in March. Since then the machine has broken many records, bringing its luminosity — the number of proton-proton collisions per second — to much higher levels than expected for this year.

We are living in perhaps the most exciting times of the past few decades in High Energy Physics: searching for the Higgs boson, as well as expected and unexpected new physics with one of the most elaborate accelerators ever built, and with complex experimental devices that took more than a decade

A search for physics beyond the standard model in events with at least three leptons and any number of jets is presented. The data sample corresponds to 35 inverse picobarns of integrated luminosity in pp collisions at sqrt(s) = 7 TeV collected by the CMS experiment at the LHC.

Curious minds might wonder why the LHC, which successfully ran at 7 TeV during the pp run of 2010 began the new year with proton collisions at a significantly less energy of 2.76 TeV.