ForewordThe Pierre Auger Observatory has begun a major Upgrade of its already impressive capabilities, with an emphasis on improved mass composition determination using the surface detectors of the Observatory. Known as AugerPrime, the upgrade will include new 4 m 2 plastic scintillator detectors on top of all 1660 water-Cherenkov detectors, updated and more flexible surface detector electronics, a large array of buried muon detectors, and an extended duty cycle for operations of the fluorescence detectors.This Preliminary Design Report was produced by the Collaboration in April 2015 as an internal document and information for funding agencies. It outlines the scientific and technical case for AugerPrime 1 . We now release it to the public via the arXiv server. We invite you to review the large number of fundamental results already achieved by the Observatory and our plans for the future.The Pierre Auger Collaboration 1 As a result of continuing R&D, slight changes have been implemented in the baseline design since this Report was written. These changes will be documented in a forthcoming Technical Design Report. ix x Executive Summary Present Results from the Pierre Auger ObservatoryMeasurements of the Auger Observatory have dramatically advanced our understanding of ultra-high energy cosmic rays. The suppression of the flux around 5×10 19 eV is now confirmed without any doubt. Strong limits have been placed on the photon and neutrino components of the flux indicating that "top-down" source processes, such as the decay of superheavy particles, cannot account for a significant part of the observed particle flux. A largescale dipole anisotropy of ∼7% amplitude has been found for energies above 8×10 18 eV. In addition there is also an indication of the presence of a large scale anisotropy below the ankle. Particularly exciting is the observed behavior of the depth of shower maximum with energy, which changes in an unexpected, non-trivial way. Around 3×10 18 eV it shows a distinct change of slope with energy, and the shower-to-shower variance decreases. Interpreted with the leading LHC-tuned shower models, this implies a gradual shift to a heavier composition. A number of fundamentally different astrophysical model scenarios have been developed to describe this evolution. The high degree of isotropy observed in numerous tests of the small-scale angular distribution of UHECR above 4×10 19 eV is remarkable, challenging original expectations that assumed only a few cosmic ray sources with a light composition at the highest energies. Interestingly, the largest departures from isotropy are observed for cosmic rays with E > 5.8×10 19 eV in ∼20 • sky-windows. Due to a duty cycle of ∼15% of the fluorescence telescopes, the data on the depth of shower maximum extend only up to the flux suppression region, i.e. 4×10 19 eV. Obtaining more information on the composition of cosmic rays at higher energies will provide crucial means to discriminate between the model classes and to understand the origin of the observed flux suppre...

We describe the physics potential of e + e − linear colliders in this report. These machines are planned to operate in the first phase at a center-of-mass energy of 500 GeV, before being scaled up to about 1 TeV. In the second phase of the operation, a final energy of about 2 TeV is expected. The machines will allow us to perform precision tests of the heavy particles in the Standard Model, the top quark and the electroweak bosons. They are ideal facilities for exploring the properties of Higgs particles, in particular in the intermediate mass range. New vector bosons and novel matter particles in extended gauge theories can be searched for and studied thoroughly. The machines provide unique opportunities for the discovery of particles in supersymmetric extensions of the Standard Model, the spectrum of Higgs particles, the supersymmetric partners of the electroweak gauge and Higgs bosons, and of the matter particles. High precision analyses of their properties and interactions will allow for extrapolations to energy scales close to the Planck scale where gravity becomes significant. In alternative scenarios, like compositeness models, novel matter particles and interactions can be discovered and investigated in the energy range above the existing colliders up to the TeV scale. Whatever scenario is realized in Nature, the discovery potential of e + e − linear colliders and the high-precision with which the properties of particles and their interactions can be analysed, define an exciting physics programme complementary to hadron machines.

We present the results of the first combined dark matter search targeting the Galactic Center using the ANTARES and IceCube neutrino telescopes. For dark matter particles with masses from 50 to 1000 GeV, the sensitivities on the self-annihilation cross section set by ANTARES and IceCube are comparable, making this mass range particularly interesting for a joint analysis. Dark matter self-annihilation through the τ þ τ − , μ þ μ − , bb, and W þ W − channels is considered for both the Navarro-Frenk-White and Burkert halo profiles. In the combination of 2101.6 days of ANTARES data and 1007 days of IceCube data, no excess over the expected background is observed. Limits on the thermally averaged dark matter annihilation cross section hσ A υi are set. These limits present an improvement of up to a factor of 2 in the studied dark matter mass range with respect to the individual limits published by both collaborations. When considering dark matter particles with a mass of 200 GeV annihilating through the τ þ τ − channel, the value obtained for the limit is 7.44 × 10 −24 cm 3 s −1 for the Navarro-Frenk-White halo profile. For the purpose of this joint analysis, the model parameters and the likelihood are unified, providing a benchmark for forthcoming dark matter searches performed by neutrino telescopes.

We calculate the cross section of diffractive charge-parity C = +1 neutral meson production in virtual photon proton collision at high energies. Due to the opposite C-parities of photon and meson M + (M + = η C , π 0 , a 2 ) this process probes the t-channel C = −1 odderon exchange which is described here as noninteracting three-gluon exchange. Estimates for the cross section of inelastic diffractive process γ * p → η C X p are presented. The total cross section of diffractive η C meson photoproduction is found to be 47 pb. The cross sections for the diffractive production of light mesons (π 0 , a 2 ) in γ * p collisions are of the same order if the photon virtuality Q 2 is m 2 C .1 Supported by German Bundesministerium für Bildung, Wissenschaft, Forschung und Technologie, grant No. 05 7LP91 P0, and in the framework of the German-Polish agreement on scientific and technological cooperation, grant No. N -115 -95. Odd charge-parity exchangeThe increase of luminosity at HERA offers the possibility of experimental investigations of diffractive processes of photo-and electroproduction of neutral charge-parity even mesons M + = π 0 , a 2 , η C at high energies (see, for example, [1]). Studies of these reactions are of great interest since the opposite chargeparities C of photon (C = −1) and M + meson cause definite C-parity C = −1 of the t-channel exchange. Consequently the pomeron exchange being most important at high energies does not contribute there. Therefore these processes allow for clean investigations of other Regge trajectories which are characterized by negative C = −1 parity.Reggeons having C = −1 are the ω trajectory and the odderon. According to fits to data on total hadron-hadron cross sections the intercept of ω trajectory is close to 0.5 [2] and its contribution decreases with energy. The odderon is the C odd partner of pomeron with an intercept ≥ 1 which has been introduced in phenomenology long time ago [3]. It is assumed that, like the pomeron, the odderon is related to gluonic degrees of freedom. The odderon exchange results in a difference between, for example, the total pp and pp cross sections which does not decrease with increasing energy. Up to now there is no indication of that difference in present high energy pp and pp data. Also odderon effects have not been observed in other soft hadronic collisions.The reasons for the absence of the odderon exchange in soft hadronic reactions remains to be understood since in perturbative QCD the pomeron and the odderon appear on the equal footing. In Leading Logarithmic Approximation (LLA) of perturbative QCD the pomeron corresponds to the exchange of two interacting reggeized gluons (hard pomeron) whereas the odderon is described by exchange of three interacting reggeized gluons (hard odderon), see [4]. In Born approximation, i.e. considering the pure three-gluon exchange in the t-channel, the intercept of the odderon is equal to 1. The effect of gluon interactions is expected to increase of odderon intercept [5]. Therefore the hard odderon ...

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