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Search for nuclearites with the SLIM detector Vlad Popa The strange quark matter (SQM) may be the ground state of GCD; if so, nuggets of SQM could be present in cosmic rays (CR), as nuclearites. SLIM is a large area experiment, using CR39 and Makrofol track etch detectors, presently deployed at the high altitude CR Laboratory of Chacaltaya, Bolivia. We discuss the expected properties of nuclearites, from the point of view of their search with SLIM. We present calculations concerning their propagation in the Earth atmosphere and the possibility to detect them with the CR39 and Makrofol nuclear track detectors, as well as some preliminary results from SLIM. back to programme A Search for Dark Matter with CACTUS Mani Tripathi CACTUS is a ground-based ACT at the Solar 2 facility located near Barstow, California and operated by UC, Davis. It uses an array of 160 large solar tracking mirrors (heliostats) and a camera with 80 photomultiplier tubes to collect atmospheric Cherenkov radiation produced by intermediate energy air showers. CACTUS has incorporated novel techniques of time projection imaging and triggering to improve upon the first generation sampling arrays of its kind. Draco is a dwarf spheroidal galaxy within the Milky Way local group and is known to be rich in Dark Matter content. Various theoretical models in high energy physics, mainly Supersymmetry, include particles that could be the basic constituent of Dark Matter. Furthermore, these particles could annihilate with each other and produce gamma rays. An excess of gamma ray emissions from Draco, for example, would lend support to such theories or else, constraint the parameters embedded in these models. We have mounted a campaign to survey the region around Draco using CACTUS. Gamma-rays from Dark Matter annihilations are expected to be in the low energy (50-200 GeV) regime. In earlier measurements of the gamma-ray emissions from the Crab nebula, we have established that CACTUS is sensitive in this energy range, thus making it well-suited for this survey. We will describe our calibrations and present an energy spectrum for gamma-rays from the Crab and for background cosmic-rays. We will also present the first results from our Draco campaign. back to programme Limits on Lorentz invariance violation in atmospheric neutrino oscillations using MACRO data Miriam Giorgini The energy spectrum of neutrino-induced upwardgoing muons in MACRO has been analysed in terms of relativity principle violating effects, keeping standard mass-induced atmospheric neutrino oscillations as the dominant source of numu --> nutau transitions. The data disfavor these exotic possibilities even at subdominant level and stringent 90% C.L. limits are placed on the Lorentz invariance violation parameter. These limits can also be reinterpreted as upper bounds on the parameters describing the violation of the equivalence principle. back to programme Indirect Dark Matter searches with AMS-02 Rosier Lees Sylvie on behalf of AMS02 The Alpha Magnetic Spectrometer (AMS), to be placed on ISS, will provide data on cosmic radiation s in a large range of energy from 0.5 GeV to 3 TeV. The main physics goals in the astroparticle domain are the anti-matter and the dark matter searches. Observations and cosmology indicate that the Universe may include a large amount of unknown Dark Matter. It should be composed of non baryonic Weakly Interactive Massive Particles (WIMP).A good WIMP candidate being the Lightest Susy Particle in R-Parity conserving models. AMS offers a unique opportunity to study simultaneously SUSY dark matter in three decay channels from the neutralino annihilation: e+, antiproton and gamma. The supersymmetric theory frame is considered together with alternative scenarios (extra dimensions). The expected flux sensitivities in 3 year exposure for the e+/e- ratio, antiproton and gamma yields as a function of energy are presented and compared to other direct and indirect searches. back to programme Gravi-Reggeons and Cosmic Neutrino-Nucleon Interactions Alexandre Kisselev The gravity effects in high-energy scattering of the SM particles confined to a brane in a space-time with extra dimensions are calculated. We consider interactions induced by gravi-Reggeon exchanges in both flat and warped metrics. The cross section for cosmic neutrino scattering off the atmospheric nucleons is estimated. back to programme Muon production in extensive air showers and its relation to accelerator measurements Christine Meurer Using CORSIKA for simulating extensive air showers, we study the relation between the shower characteristics and features of hadronic multiparticle production at low energies. We report about investigations of typical energies and phase space regions of secondary particles which are important for muon production in extensive air showers. Possibilities to measure relevant quantities of hadron production in existing and planned accelerator experiments are discussed. back to programme Impact of uncertainties in hadron production on air shower predictions Tanguy Pierog Main observables of high energy air showers mainly depend on the nature and energy of the primary particles. As a result, simulation of showers initiated by hadronic particles will have a strong dependence on the hadronic interaction model used. Although the main hadronic air shower development can be understood within a simplified model of hadron production, detailed simulations and a realistic description of hadronic interactions are needed to calculate observables relevant for air shower experiments. We will study the effect of using different hadronic models available for cosmic ray calculation on extensive air shower predictions within CORSIKA and CONEX. back to programme Models for cosmic ray interactions S. Ostapchenko Contemporary models of hadronic interactions are reviewed. Basic phenomenological approaches are compared, with an emphasises on the predicted air shower characteristics. A special attention is payed to the remaining discrepances between present hadronic MC generators and cosmic ray data. Finally, future prospects concerning model improvements are discussed, in particular, regarding the possibilities to discriminate between different models on the basis of accelerator and cosmic ray measurements. back to programme Photon air showers at ultra-high energy and the photonuclear cross-section Markus Risse The origin of cosmic rays with energies of 10^20 eV and more is one of the large puzzles in contemporary astroparticle physics. In some non-acceleration source models, a large fraction of these particles are predicted to be photons. One can check whether cosmic-ray events observed by large air shower experiments are compatible with expectations for primary photons by comparing to simulations of photon-initiated air showers. Among other processes, such simulations require the photonuclear cross-section to be extrapolated over several decades in energy. On one hand, the corresponding theoretical uncertainty affects the photon shower simulations and translates into a systematic uncertainty when deriving experimental limits on the primary photon flux. On the other hand, an upper limit on the photonuclear cross-section could be given if photon-induced showers were observed. The status of primary photon simulations, recent results from comparisons to data, and the influence when changing the extrapolation of the photonuclear cross-section will be presented. back to programme Cosmic Ray Studies with the L3-Cosmics Program at CERN Lawrence W. Jones The L3 detector at the CERN electron-positron collider had a muon spectrometer which was employed during the last years of LEP operation for cosmic ray studies. The results of this program include a precise muon spectrum and charge ratio between 20 GeV and 3 TeV, a limit on TeV primary antiprotons from a study of the Moon's shadow, the (possible) observation of a flare signal from a fixed position in the northern hemisphere through muons, a solar anisotropy of 200 GeV protons, and other results. Negative limits on muons associated with known H.E. gamma sources or gamma bursts, the search for anomalous H.E. interaction or decay events such as reported from the Kolar Gold Fields, and a search for muons correlated with a solar flare are also noted. back to programme Geometric structures in hadronic cores of extensive air showers observed by KASCADE Markus Risse The geometric distribution of high-energy hadrons >100 GeV in shower cores measured with the KASCADE calorimeter is analyzed. The data are checked for sensitivity to hadronic interaction features and indications of new physics as discussed in the literature. The angular correlation of the most energetic hadrons and in particular the fraction of events with hadrons being aligned are quantified by means of the commonly used parameter lambda_4. The analysis shows that the observed lambda_4 distribution is compatible with that predicted by simulations and is not linked to an angular correlation from hadronic jet production at high energy. Another parameter, d_4^max, describing distances between hadrons measured in the detector, is found to be sensitive both to the transverse momenta in secondary hadron production and the primary particle type. Transverse momenta in high-energy hadron interactions differing by a factor two or more from what is assumed in the standard simulations are disfavoured by the measured d_4^max distribution. back to programme Atmospheric muon and neutrino fluxes and hadronic interaction Morihiro Honda The muon fluxes at several altitudes are examined with the simulation code used by HKKM04. This study makes it possible to estimate the uncertainty in the atmospheric neutrino flux calculated by HKKM04, which is less than 10~\% in 1--10 GeV. It also provides us a method to calibrate the interaction model, and we find that DPMJET-III, the interaction model used by HKKM04, needs to be modified at high energies. We propose a modification of DPMJET-III, and present the results with the modified interaction model. back to programme The Double-Bang Shower Event Rates of Ultrahigh Energy Tau Neutrinos in the Rock Salt: Results from Standard Model and Beyond Standard Model Physics Guey-Lin Lin We perform a simulation on the double-bang shower event rates of GZK tau neutrinos in the rock salt, taking into account propagations and energy losses of tau neutrinos and tau leptons in various density components of the earth. As an illustration, the rock salt region is taken as spherical in shape with a radius R=5 km. Such a region is treated as about 2 km below the earth surface. We present the simulation results based upon Standard Model Particle Physics and the TeV Scale Gravity Theory. The angular distributions of the events are studied and the criteria for distinguishing the above two models are proposed. back to programme A measurement of shower lateral and longitudinal profiles using the 1.5 GeV electron beams on aluminum targets at National Synchrotron Radiation Research Center (NSRRC) in Taiwan: A Status Report Guey-Lin Lin We perform the shower profile measurements by shooting the 1.5 GeV electron beams in NSRRC on targets made of 15 aluminum blocks, each with a thickness of 2.9 cm. A scintillator (Al2O3: Cr)) is placed behind the targets, converting the secondary shower particles into light. The light from the central region of the shower is recorded by a CCD camera while the light from the outer region is monitored by PMTs. The CCD system has been successfully implemented in the run 2 and run 3 of the experiment FLASH at SLAC. A test run of the current experiment has been conducted in NSRRC in the past June to study the scintillator spectra. Two more runs are planned from now to the year 2006 to measure the shower lateral and longitudinal profiles. back to programme Hadron production at forward rapidity in nuclear collisions at RHIC Hongyan Yang We will present hadron production in ultra-relativistic heavy ion collisions, which has been measured by BRAHMS experiment at RHIC. The rapidity dependence of the nuclear modification factor will be compared to models in order to differentiate between initial state gluon saturation effect and final state effect like parton recombination. The net-proton distribution in p+p, d+Au and Au+Au collisions will be shown to study the high energy collision scenario - transparency and stopping. Very preliminary results on radial and elliptic flow measured by BRAHMS will be included. back to programme Reconstruction of energy spectra of elemental groups with KASCADE: sensitivity to hadronic interaction models Holger Ulrich The large field array of the KASCADE experiment (located at Forschungszentrum Karlsruhe, Karlsruhe, Germany) measures with high accuracy the electromagnetic and muonic component of extensive air showers. The two-dimensional frequency distribution of these observables is used for reconstructing the energy spectra of five elemental groups by means of unfolding methods. These elemental groups represent the chemical composition of primary cosmic rays around the knee. The results of the analysis are based on a vast number of Monte Carlo simulations using different high-energy hadronic interaction models. As it turns out, the description of the measured data by the simulations shows to be sensitive to the characteristics of the used interaction models. Moreover, none of the used models (QGSJet and SIBYLL) is capable to describe the data consistently over the whole measurement range. Results of the analysis and their implications will be discussed. back to programme NEMO - a km3 Neutrino Telescope in the Mediterranean Sea Mauro Taiuti The NEMO (NEutrino Mediterranean Observatory) Project aims at the construction of a km3-scale neutrino telescope in the Mediterranean Sea. After extensive deep-sea surveys performed in several sites in the Mediterranean, an optimal installation site for the apparatus has been identified at a depth of 3500 m, about 80 km off Capo Passero, at the SE corner of Sicily, Italy. In this talk, we will illustrate the apparatus design and discuss its simulated capabilities. We will then illustrate the results of our long-lasting R&D efforts toward the construction of the apparatus. The NEMO Project has recently entered its Phase 1, aimed at the construction, deployment and operation of a subsystem which includes all the key elements of the apparatus at a test site located at a depth of 2000 m, about 25 km off the coast of Catania. A prototype hydrophone station for acoustic observations of high-energy neutrinos (ONDE) is currently in operation at this test site. The cable for connecting the Capo Passero deep-sea site to the shore is under design, and the work to set up the shore station has started. The plan is to install a full-size tower at this location in two years. back to programme The LHCf experiment at LHC Adriani Oscar The LHCf experiment will be installed in 2007 on the LHC collider, 140 m away from one of the interaction points, to precisely measure the pion production cross section at a very small angle through the measurement of the photons produced in the neutral pion decay. This measurement is crucial for the simulation of the showers induced in the atmosphere by very high energy cosmic rays; the 14 TeV energy available in the center of mass frame corresponds in fact to an equivalent energy of 10^17 eV in the laboratory system. The presentation will mainly be focused on the description of the proposed experiment and on the physics results that we expect from it. back to programme Discovery Potential of the LHC Ketevi A. Assamagan The physics program at the LHC includes precision tests of the Standard Model (SM), the search for the SM Higgs boson up to 1 TeV, the search for the MSSM Higgs bosons in the entire parameter space, the search for Super Symmetry, sensitivity to alternative scenarios such as compositeness, large extra dimensions, etc. This requires general purpose detector with excellent performance. ATLAS is one such detectors under construction for the LHC. Data taking is expected to start in April 2007. The detector performance and the prospects for discoveries are studied in various physics working groups. In this talk, we will review discovery potential of the LHC. back to programme EMMA - Experiment with MultiMuon Array Sarkamo Juho We are developing a new underground cosmic ray experiment EMMA (Experiment with MultiMuon Array). The EMMA-experiment will measure the multiplicity and lateral distribution of high energetic muons originated near the primary collision point of a cosmic ray air shower. The experiment will be set up at shallow depths underground in Pyhäsalmi Mine in Central Finland and it will be optimized to study air showers with primary energies around the knee region. At the first phase EMMA will consist of two or three separate detector units with an area of about 50 m2 each with a mutual distance of 20 m. We will use old Delphi Muon Barrel Chambers for the muon multiplicity and position measurements. Our simulations show that the measurements of lateral distribution of high energy muons can be used to deduce the primary composition. Hence EMMA can shed light on the composition and air shower development from a different point of view. back to programme Latest Results from the High Resolution Fly's Eye (HiRes) Experiment Charles Jui The High-Resolution Fly's Eye (HiRes) is an air-fluorescence observatory located in Utah, USA with the mission of measuring the energy spectrum, chemical composition, and arrival directions of the highest energy cosmic rays. HiRes has been collecting monocular data since 1997 and stereo data since 1999, and has accumulated the largest integrated aperture at the highest energies of any UHECR observatory to date. We present the latest monocular and stereo spectra, results of searches for arrival direction anisotropy, and composition measurements. back to programme Detection of cosmic rays by LEP experiments Petr Travnicek Accelerator experiments located at LEP collider have been used also to detect cosmic ray events. Various results obtained by Cosmo-ALEPH, DELPHI and L3+C collaborations will be described. Emphasis will be put on detection of multi-muon bundles and comparisons of the measurements with Monte-Carlo simulations based on current models of primary hadron-hadron interactions. The analysis of inclusive muon energy spectra and muon charge ratio by Cosmo-Aleph and L3+C collaborations will be also explained. Other topics such as source searches, limits on anti-proton/proton flux calculated from moon shadow, solar flare studies etc. will be briefly mentioned. back to programme Radio Detection of Ultra High Energy Neutrinos: ANITA and SalSA for both Astrophysics and Particle Physics Gary S. Varner The primary objective of the ANtarctic Impulsive Transient Antenna (ANITA) mission is to investigate and constrain the nature of the sources of high energy cosmic ray particles above 100 EeV, by measurements of neutrinos that are strongly believed to be both spectrally and spatially correlated to them. Observation over the last 40 years of several dozen cosmic ray events with energies exceeding the Greisen-Zatsepin-Kuzmin (GZK) cutoff poses among the most intriguing and intractable problems in high energy astrophysics. Operating from a long-duration balloon at an altitude of 37km, ANITA will synoptically observe the Antarctic ice sheet out to a horizon of more than 600km, giving a detection volume of order 1 million cubic kilometers. ANITA will search for radio pulses that arise from electromagnetic cascade interactions of high energy neurinos within the ice. Such radio pulses, recently confirmed in accelerator experiments, easily propagate through the ice due to its remarkable radio transparency. A preliminary design and technical challenges of the low-power radio frequency instrumentation will be presented. Time permitting, the application of this Askaryan-effect detection technique to naturally occuring salt domes (Salt dome Shower Array [SalSA] will be mentioned. Such a large detector would enable the use of GZK neutrinos to search for new physics at center-of-mass energies well beyond the reach of the LHC. If there is interest, results from a detector prototype, will be provided. back to programme On universal limit for the cross sections of hadron-hadron, hadron-nucleus and nucleus-nucleus collisions at superhigh energies Leonid Frankfurt We will explain that blackening of interactions in the high energy collisions at central impact parameters is direct consequence of compositeness of projectile in QCD and increase with energy of cross sections. Relationship between this property of high energy processes and phenomenon of spontaneous violation of continious symmetries will be visualised. Account of these phenomena leads to increase with energy of radius of interactions and to observable effects at achievable energies and at superhigh energies to universal limit for all cross sections: $\sigma(pp):\sigma(pA):\sigma(AA)> \to 1$ The same universality is expected for structure functions of nucleons and nuclei,for cross section of photodesintegration of nucleons and nuclei etc. back to programme Exotic Physics With Cosmic Neutrinos Dan Hooper Although collider experiments are often thought of as the primary tool in testing physics beyond the Standard Model, astroparticle physics experiments have characteristics which make them highly complementary probes. In this talk, I will review the ability of neutrino telescopes and cosmic ray experiments to measure the interaction cross sections of neutrinos at energies well beyond those accessible to colliders. I will also discuss the use of high and ultra-high energy cosmic neutrinos as an ultra-long baseline measurement. Such experiments can be used to constrain -- or potentially discover -- signatures of exotic physics, including low scale quantum gravity, Standard Model electroweak instanton induced interactions, neutrino decay and quantum decoherence. back to programme The Elusive p-air Cross Section - tying together accelerator sigma_pp and cosmic ray sigma_p-air^inel measurements Martin Block We fit {\em all} of the extensive accelerator data of the Particle Data Group ($\sigma_{pp},\sigma_{\bar pp},\rho_{pp},\rho_{\bar p p}$) with c.m.s. energy $6 \ {\rm GeV}\le\sqrt s\le 1800$ GeV, using real analytic amplitudes that saturate the Froissart bound, {\em i.e.}, the cross section rises as $\ln^2 s$. However, we then subject these data to a screening process, the ``Sieve'' algorithm[M.M. Block, physics/0506010], in order to eliminate ``outliers'' that can skew a $\chi^2$ fit. With the ``Sieve'' algorithm, a robust fit using a Lorentzian distribution is first made to all of the data to sieve out abnormally high $\delchi$, the individual i$^{\rm th}$ point's contribution to the total $\chi^2$. The $\chi^2$ fits are then made to the sieved data. We show that both the nucleon-nucleon and $\pi p$ systems fit exceedingly well to a high energy $\ln^2s$ fit of the form: $\sigma^{\pm}=c_0 +c_1{\ln }\left({\nu\over m}\right)+c_2{\ln }^2\left ({\nu\over m}\right)+\beta_{\cal P'}\left({\nu\over m}\right)^{\mu -1}\pm \delta\left({\nu\over m}\right)^{\alpha -1}$, using the equivalent of finite energy sum rules to anchor the fits to the low energy data just above the resonance regions[M. M. Block and F. Halzen, Phys. Rev. D {\bf72}, 036006 (2005)]. The upper sign is for $pp$ ($\pi^+p$) and the lower sign is for $\bar pp$ ($\pi^-p$) scattering, where $\nu$ is the laboratory proton (pion ) energy, and $m$ is the proton (pion) mass. The fitting technique allows us to make very accurate predictions at cosmic ray energies, {\em e.g.}, $\sigma_{pp}=131.1\pm1.7$ mb at $\sqrt s=50$ Tev. The $\ln^2s$ fit that we find, along with a QCD-inspired eikonal fit[M. M. Block, F. Halzen and T. Stanev, Phys. Rev. D {\bf 62}, 077501 (2000)] for B, the nuclear slope in the forward direction, allows us to make a Glauber calculation[M. Block and R. Engel, unpublished] using a two-channel inelastic screening model, to predict $\sigma_{\rm p-air}^{\rm inel}$ at cosmic ray energies. These results are compared to the new HiRes experimental value, $\sigma_{\rm p-air}^{\rm inel}=456\pm17_{\rm stat}+39_{\rm syst}-11_{\rm syst}$, along with AGASA and Fly's eye data, giving us a benchmark for tying together accelerator and cosmic ray data. back to programme The Auger Observatory: Status and first results Enrique Zas More than half of the Auger Observatory has been constructed and is opertating in Malargue, Mendoza, Argentina. We present a review of the observatory, its goals and perspectives and a summary of the first scientific results. back to programme CREAM Opher Ganel Pushing the High Energy Frontier of Directly Measured Cosmic Rays After nearly a century since their discovery, much is still uncertain about cosmic rays, including their source, acceleration mechanism, and propagation. Direct measurement of cosmic ray elemental spectra in the critical energy range of 1012 - 1015 eV offers a promising avenue to answering these questions. The Cosmic Ray Energetics And Mass (CREAM) experiment was launched from McMurdo Station, Antarctica, under a NASA research balloon on December 16, 2004. Floating for nearly 42 days at altitudes between 36 and 39 km, CREAM collected over 4x107 events. Preliminary results show great promise for this dataset. CREAM-II is set to launch in December 2005, with a refurbished CREAM planned to fly again in 2006. This presentation will examine the experimental context of CREAM, describe the detector, and show preliminary results from accelerator beam tests and the first flight. back to programme The Structure of the Nucleon and Simulation of Cosmic Ray Showers" Terry Sloan In this talk the structure of the nucleon will be reviewed using the picture that has emerged from studies of deep inelastic lepton-nucleon scattering. The successes of the quark-parton model of the nucleon in interpreting the data and what they reveal about the strong force, QCD, will be described. Some of the remaining problems will be described. Finally the difficulties implied for the simulation of high energy cosmic showers will be discussed. back to programme Diffraction and Forward physics at the LHC Albert de Roeck The central detectors ATLAS and CMS can measure particles up to pseudo-rapidity values of 5. The TOTEM detector, which uses the same interaction point as CMS, can measure particles in the range 3< eta <5 and has roman pots to measure leading protons. CMS is furthermore considering additional calorimeters in the forward region, with an acceptance of up to 7 in pseudorapidity. Also ATLAS is developing plans for additional forward detectors. The combination of e.g. CMS and TOTEM and their common data taking will give a detector with unprecedented acceptance in the combined central and forward region. This talk will present these possible upgrades and the physics potential of the LHC detectors in the forward region, with for example QCD measurements in the area of diffraction and low-x physics. Moreover recently central exclusive production of the Higgs bosons has gained a lot of interest and will be discussed. back to programme |
