No abstract

review the design and construction of the detector and of its related infrastructures, and report on some technical performances of the various components. The construction of the detector started in 2003 and it was completed in Summer 2008. The experiment is presently in the data taking phase. The whole sequence of operations has proven to be successful, from triggering to brick selection, development, scanning and event analysis.

Heavy Neutral Leptons (HNLs) are hypothetical particles predicted by many extensions of the Standard Model. These particles can, among other things, explain the origin of neutrino masses, generate the observed matter-antimatter asymmetry in the Universe and provide a dark matter candidate. The SHiP experiment will be able to search for HNLs produced in decays of heavy mesons and travelling distances ranging between O(50 m) and tens of kilometers before decaying. We present the sensitivity of the SHiP experiment to a number of HNL's benchmark models and provide a way to calculate the SHiP's sensitivity to HNLs for arbitrary patterns of flavour mixings. The corresponding tools and data files are also made publicly available.

An overview of the electromagnetic (EM) physics of the Geant4 toolkit is presented. Two sets of EM models are available: the "Standard" initially focused on high energy physics (HEP) while the "Low-energy" was developed for medical, space and other applications. The "Standard" models provide a faster computation but are less accurate for keV energies, the "Low-energy" models are more CPU time consuming. A common interface to EM physics models has been developed allowing a natural combination of ultra-relativistic, relativistic and low-energy models for the same run providing both precision and CPU performance. Due to this migration additional capabilities become available. The new developments include relativistic models for bremsstrahlung and e+e-pair production, models of multiple and single scattering, hadron/ion ionization, microdosimetry for very low energies and also improvements in existing Geant4 models. In parallel, validation suites and benchmarks have been intensively developed.

The double-differential production cross-section of positive pions, d 2 σ π + /dpdΩ, measured in the HARP experiment is presented. The incident particles are 8.9 GeV/c protons directed onto a beryllium target with a thickness of 5% of a nuclear interaction length. The measured cross-section has a direct impact on the prediction of neutrino fluxes for the MiniBooNE and SciBooNE experiments at Fermilab. After cuts, 13 million protons on target produced about 96,000 reconstructed secondary tracks which were used in this analysis. Cross-section results are presented in the kinematic range 0.75 GeV/c ≤ pπ ≤ 6.5 GeV/c and 30 mrad ≤ θπ ≤ 210 mrad in the laboratory frame.PACS. PACS-key discribing text of that key -PACS-key discribing text of that key