[en] A few years ago the AMS01 embarked experiment showed a particular high component of the cosmic particle flux detected below the geo-magnetic cut which was surprising because this cut represents the minimal energy that is required for cosmic radiation to reach the earth and any cosmic ray below the cut is pushed away by the earth's magnetic field. This work is based on Monte-Carlo simulations involving the generation of primary cosmic particles, their propagation in the earth magnetic field, their interaction with earth's atmosphere and the production of secondary particles. These simulations have shown that the particles below the cut are in fact particles generated in the upper part of the atmosphere, escaping from it and being trapped by the earth's magnetic field. These Monte-Carlo simulations have also been used to assess the composition of below-the-cut flux in terms of protons, electrons, positrons and light nuclei, to check the production of anti-matter in the atmosphere, and to estimate the flux of atmospheric neutrinos. (A.C.)

[en] A precise evaluation of the secondary particle production and propagation in the atmosphere is very important for the atmospheric neutrino oscillation studies. The issue is addressed with the extension of a previously developed full 3-dimensional Monte-Carlo simulation of particle generation and transport in the atmosphere, to compute the flux of secondary protons, muons, and neutrinos. Recent balloon borne experiments have performed a set of accurate flux measurements for different particle species at different altitudes in the atmosphere, which can be used to test the calculations for the atmospheric neutrino production, and constrain the underlying hadronic models. The simulation results are reported and compared with the latest flux measurements. It is shown that the level of precision reached by these experiments could be used to constrain the nuclear models used in the simulation. The implication of these results for the atmospheric neutrino flux calculation are discussed

[en] We developed a highly integrated and versatile electronic module to equip small nuclear physics experiments and lab teaching classes: the User friendly Configurable Trigger, scaler and delay Module for nuclear and particle physics (UCTM). It is configurable through a Graphical User Interface (GUI) and provides a large number of possible trigger conditions without any Hardware Description Language (HDL) required knowledge. This new version significantly enhances the previous capabilities by providing two additional features: signal digitization and time measurements. The design, performances and a typical application are presented.

[en] The atmospheric muon and neutrino flux have been simulated using the same approach which successfully accounted for the recent secondary proton, electron, and positron flux measurements in orbit by the AMS experiment. For the muon flux, good agreement is obtained with the CAPRICE and HEAT data for altitudes ranging from sea level up to about 38 km. The general features of the calculated atmospheric neutrino flux are reported and discussed. The flux obtained at the Super-Kamiokande experiment location are reported and compared with other calculations. For low neutrino energies the flux obtained is significantly smaller than that used in the data analysis of underground experiment. The simulation results for the SOUDAN experiment site are also reported

[en] Anti-hydrogen atoms have been produced in the experiments Alpha and Asacusa at the CERN. 38 atoms of anti-hydrogen have been trapped for 0.172 s in the Alpha experiment. This is the first step towards a real study of the properties of anti-matter. 2 experiments have been imagined to test the effect of gravity on anti-matter, first results are not expected before 2015. A new detector AMS will be installed on the ISS (International Space Station) on the last flight of the Endeavour shuttle. AMS will detect particles and anti-particles that go through the universe. The detection of only 1 nucleus of anti-carbon would be the proof of the existence of an anti-world, on the contrary the no-detection of anti-heavy-nuclei will comfort the theory of an asymmetrical universe. In the standard cosmological model, the universe has lost its original symmetry: matter has triumphed over anti-matter. Another cosmological model supposes a symmetrical universe that links anti-matter to negative mass. This model explains that positive mass tends to aggregate while negative mass tends to go away. This model describes a slow expansion of the universe with no need for the existence of dark matter and dark energy. (A.C.)

[en] The atmospheric secondary antiproton flux is studied for detection altitudes extending from sea level up to about three earth radii, by means of a three-dimensional Monte Carlo simulation, successfully applied previously to other satellite and balloon data. The calculated antiproton flux at mountain altitude is found to be in fair agreement with the recent BESS measurements. The flux obtained at balloon altitude is also in agreement with calculations performed in previous studies and used for the analysis of balloon data. The flux at sea level is found to be significant. The antineutron flux is also evaluated. The antiproton flux is prospectively explored up to around 2x10⁴ km from the Earth. The results are discussed in the context of the forthcoming measurements by large acceptance experiments

[en] The atmospheric secondary proton flux is studied for altitudes extending from sea level up to the top of the atmosphere by means of a three-dimensional Monte Carlo simulation procedure successfully used previously to account for flux measurements of protons, light nuclei, and electron-positron pairs below the geomagnetic cutoff (satellite data), and of muons and antiprotons (balloon data). The calculated fluxes are compared with the experimental measurements from sea level up to high float balloon altitudes. The agreement between data and simulation results is very good at all altitudes, including the lowest ones, where the calculations become extremely sensitive to the proton production cross section. The results are discussed in this context. The calculations are extended to the study of quasitrapped particles above the atmosphere to about five earth radii, for prospective purpose

[en] A simple coalescence model based on the same diagrammatic approach of antimatter production in hadronic collisions as used previously for antideuterons is used here for the hadroproduction of mass-3 antinuclei. It is shown that the model is able to reproduce the existing experimental data on the anti t and ³He production without any additional parameter. (orig.)

[en] The atmospheric muon and neutrino flux have been simulated using the same approach which successfully accounted for the recent secondary proton, electron and positron flux measurements in orbit by the AMS experiment. For the muon flux, a good agreement is obtained with the CAPRICE and HEAT data for altitudes ranging from sea level up to about 38 km. The general features of the calculated atmospheric neutrino flux are reported and discussed. The flux obtained at the Super-Kamiokande experiment location are reported and compared with other calculations. For low neutrino energies the flux obtained is significantly smaller than that used in the data analysis of underground experiment. The simulation results for the SOUDAN experiment site are also reported. (authors)

[en] The Grenoble Subatomic Physics and Cosmology Laboratory - LPSC aims to improve our knowledge about the most elementary particles and about the forces that govern their interactions. It helps to broaden our understanding of the universe, its structure and its evolution. The LPSC is a Mixed Teaching and Research Unit, affiliated to the National Nuclear and Particle Physics Institute (IN2P3), the National Institute of Universe Sciences (INSU) and the National Institute of Engineering Sciences and Systems (INSIS) from the National Centre for Scientific Research (CNRS), as well as to the Joseph Fourier University and the Grenoble National Polytechnique Institute. The LPSC also plays a significant role at the national level and is involved in several international scientific and technical projects. Fundamental research is the driving force of LPSC activities. Among the themes studied at the LPSC, some are focused on the greatest unsolved mysteries of the universe, e.g. the unification of forces, the origin of the mass of particles, the origin of the matter-antimatter asymmetry in the universe and the search for dark matter and energy. Research starts at the scales of the nuclei of atoms and even much smaller, where quantum and relativistic physics laws prevail. The goal here is to understand the characteristics of the most elementary building blocks of matter and their interactions, to study the limits of existence of atoms and to discover new states of nuclear matter, such as the quark-gluon plasma. Research also extends towards the infinitely large; the goal here is to understand the origin of the structures of the universe and the cosmic phenomena that take place, and to understand the characteristics of the very first stages of the universe, just after the Big Bang. The branches of physics at these two extremes are actually closely linked. Infinitely small-scale physics plays an essential role in the first moments of the universe. Particle physics and cosmology both seek answers to the existence of dark matter and dark energy in the universe. The locations of the experiments are very diverse: ground-based, underground-based or even satellite-based. LPSC also studies artificially created short-lived particles (created by accelerators which our laboratory helps to design) or cosmic particles that were produced at different epochs of the history of the universe. These activities require the development of sophisticated, state-of-the-art instrumentation. A close collaboration between physicists, engineers and technicians is required to achieve the required performance. In addition, a strong theoretical research activity supports the experiments during the preparatory stages and during the data analysis. This report presents the activities of the laboratory during the years 2004-2005: 1 - Forewords; 2 - Quarks, leptons and FUNDAMENTAL INTERACTIONS (DΦ, ATLAS, Ultra-cold Neutrons - UCN); 3 - Cosmology and cosmic radiations (AMS-CREAM, Archeops-Planck, MIMAC-He3, EUSO-ULTRA); 4 - Hadrons and nuclei (nucleons and light nuclei structure, GRAAL, Reactor physics); 5 - pluri-disciplinary programs (physics-medicine interface, ETOILE, Research centre on plasmas-materials-nano-structures - CRPMN); 6 - Theory; 7 - Accelerators and ion sources; 8 - Technical and administrative Services: detectors and Instrumentation, Mechanics, Electronics, Data acquisition and Computers departments, General services, Communication, Technology Valorisation and transfer, Administration; 9 - Communication; 10 - Human resources, Health and safety; 11 - Staff and organigram; 12 - Training and teaching; 13 - Publications; 14 - Redaction committee