Good Perspectives for Social Protection in Angola

Good Perspectives,Social Protection, Angola

Social Protection in Ghana

Social, Protection, Ghana

Study Tour Africa-Brazil on Social - Promotion and Protection

Study Tour, Africa-Brazil, Social, Promotion and Protection

Social Policies in a Period of Crisis

Social Policies, Period of Crisis

New H1 results on isolated leptons and missing pt at HERA

The search for events containing isolated leptons (electrons or muons) and missing transverse momentum produced in $e^{\pm}p$ collisions is performed with the H1 detector at HERA in the period 1994--2005. The analysed data sample corresponds to an integrated luminosity of 279 pb$^{-1}$, which includes 53 pb$^{-1}$ of $e^{+}p$ data and 107 pb$^{-1}$ of $e^{-}p$ data from the new HERA~II phase. A total of 40 events are observed in the data, compared to a Standard Model (SM) prediction of 34.3 $\pm$ 4.8. At large hadronic transverse momentum $P_{T}^{X} >$ 25 GeV, a total of 17 events are observed compared to 9.0 $\pm$ 1.5 predicted by the SM. In this region, 15 events are observed in the $e^{+}p$ data compared to a SM prediction of 4.6 $\pm$ 0.8, whereas in the $e^{-}p$ data 2 events are observed compared to a SM prediction of 4.4 $\pm$ 0.7.Comment: 4 pages, 4 figure; To appear in the proceedings of 14th International Workshop on Deep Inelastic Scattering (DIS 2006), Tsukuba, Japan, 20-24 Apr 200

Multi-Lepton and Isolated Lepton Events at HERA

Measurements of the production of events containing isolated high energy leptons (electrons and muons) produced in ep collisions have been performed with the H1 and ZEUS detectors at HERA, using data collected in the period 1994-2007. Topologies with more than one charged lepton or with a charged lepton in coincidence with missing transverse momentum are analysed. The H1 and ZEUS data, corresponding to an integrated luminosity of about 0.5 fb^-1 per experiment, are combined in a common phase space. The observed event yields are compared to the predictions from the Standard Model. In general a good agreement is found, where the expectation is dominated by photon-photon collisions for the multi-lepton topologies and by single W production in the case of events with an isolated electron or muon and missing transverse momentum. Events with large transverse momentum are observed. Total and differential cross sections of these processes are measured.Comment: Proceedings of the talk given at The 2009 Europhysics Conference on High Energy Physics (EPS-HEP 2009), 16-22 July 2009, Krakow, Poland. 4 pages, 3 figures; one style file, one log