Analysis strategy for the SM Higgs boson search in the four-lepton final state in CMS

The current status of the searches for the SM Higgs boson in the $H$$\rightarrow$$ZZ^{(*)}$$\rightarrow$$4\ell$ decay channel with the CMS experiment is presented. The selection cuts for suppressing the backgrounds while keeping very high signal efficiencies are described, along with the data-driven algorithms implemented to estimate the background yields and the systematic uncertainties. With an integrated luminosity of $1.66 \mathrm{fb}^{-1}$, upper limits at 95% CL on the SM-like Higgs cross section $\times$ branching ratio exclude cross sections from about one to two times the expected value from the Standard Model in the range $150 < m_{H} < 420 \mathrm{GeV}$. No evidence for the existence of the SM Higgs boson has been found so far.Comment: "Presented at the 2011 Hadron Collider Physics symposium (HCP-2011), Paris, France, November 14-18 2011, 3 pages, 5 figures.

LHC collimator alignment operational tool

Beam-based LHC collimator alignment is necessary todetermine the beam centers and beam sizes at the colli-mator locations for various machine configurations. Fastand automatic alignment is provided through an opera-tional tool has been developed for use in the CERN Con-trol Center, which is described in this paper. The tool isimplemented as a Java application, and acquires beam lossand collimator position data from the hardware through amiddleware layer. The user interface is designed to allowfor a quick transition from application start up, to select-ing the required collimators for alignment and configuringthe alignment parameters. The measured beam centers andsizes are then logged and displayed in different forms tohelp the user set up the system.peer-reviewe

A systematic measurement analyzer for LHC operational data

The CERN Accelerator Logging Service stores data from hundreds of thousands of parameters and measurements, mostly from the Large Hadron Collider (LHC). The systematic measurement analyzer is a Java-based tool that is used to visualize and analyze various beam measurement data over multiple fills and time intervals during the operational cycle, such as ramp or squeeze. Statistical analysis and various manipulations of data are possible, including correlation with several machine parameters such as β^{*} and energy. Examples of analyses performed include checks of collimator positions, beam losses throughout the cycle and tune stability during the squeeze which is then used for feed-forward purposes.peer-reviewe