15551136
HADRONIC INTERACTIONS, PRECOCIOUS UNIFICATION, AND COSMIC RAY SHOWERS AT AUGER ENERGIES
At Auger energies only model predictions enable us to extract primary cosmic ray features. The simulation of the shower evolution depends sensitively on the first few interactions, necessarily related to the quality of our understanding of high energy hadronic collisions. Distortions of the standard "soft semi-hard" scenario include novel large compact dimensions and a string or quantum gravity scale not far above the electroweak scale. Naively, the additional degrees of freedom yield unification of all forces in the TeV range. In this letter we study the influence of such precocious unification during atmospheric cascade developments by analyzing the most relevant observables in-proton induced showers.
119056773
THE MYSTERIOUS ULTRAHIGH ENERGY COSMIC RAY CLUSTERING
We examine the correlation between compact radio quasars (redshifts in the range z=0.3–2.2) and the arrival direction of ultrahigh energy cosmic rays forming clusters. Our Monte Carlo simulation reveals a statistically significant correlation on the AGASA sample: the chance probability of this effect being less than 1%. The implications of this result on the origin of ultrahigh energy cosmic rays are discussed.
13042203
Extensive air showers with TeV scale quantum gravity
One of the possible consequences of the existence of extra degrees of freedom beyond the electroweak scale is the increase of neutrino-nucleon cross sections ({sigma}{sub {nu}N}) beyond standard model predictions. At ultrahigh energies this may allow the existence of neutrino-initiated extensive air showers. In this paper, we examine the most relevant observables of such showers. Our analysis indicates that the future Pierre Auger Observatory could be potentially powerful in probing models with large compact dimensions.
10475979
Primordial Fluctuations from Gaugino Condensation
I present a model for inflation based on the gaugino-dilaton dynamics of supersymmetry breaking. The inflaton is the dimension–1 scalar field φ related to the gaugino condensate via λT λ = φ. Recent work in this area is used to obtain two significant results: (1) Scalar density fluctuations at second horizon crossing are generated on scale λ with amplitude
120429995
PREDICTIONS FOR INCLUSIVE REACTIONS BASED ON A PARTON STRUCTURE OF HADRONS.
Abstract It is proposed that the asymptotic single-particle distributions f ( x )= x (d σ /d x ) in inclusive reactions should reflect the limiting longitudinal momentum distribution, ∼ νW 2 ( x ), of the hypothetical partons constituting a hadron. It is further argued that f ( x ) becomes, proportional to νW 2 ( x ) as x → 1. Predictions are then made for a large class of inclusive reactions based on our knowledge of νW 2 ( x ) from electroproduction data. For some of these (such as pp → π ± X), in which the predictions differ markedly from the Regge ones, present experiments distinctly favor ours.
119188244
LHC phenomenology of lowest massive Regge recurrences in the Randall-Sundrum orbifold
We consider string realizations of the Randall-Sundrum effective theory for electroweak symmetry breaking and explore the search for the lowest massive Regge excitation of the gluon and of the extra (color singlet) gauge boson inherent in D-brane constructions. In these curved backgrounds, the higher-spin Regge recurrences of standard model fields localized near the IR brane are warped down to close to the TeV range and hence can be produced at collider experiments. Assuming that the theory is weakly coupled, we make use of four gauge boson amplitudes evaluated near the first Regge pole to determine the discovery potential of LHC. We study the inclusive dijet mass spectrum in the central rapidity region |y{sub jet}| =}2.5 TeV. We find that with an integrated luminosity of 100 fb{sup -1}, the 5{sigma} discovery reach can be as high as 4.7 TeV. Observations of resonant structures in pp{yields}direct{gamma}+jet can provide interesting corroboration for string physics up to 3.0 TeV. We also study the ratio of dijet mass spectra at small and large scattering angles. We show that with the first fb{sup -1} such a ratio can probe lowest-lying Regge states for masses {approx}2.5 TeV.
118297532
A Study of hadronic final states produced in association with high pT jets and high - mass dimuons
120314760
A Study of Jet Like Structure in High Transverse Energy Events Produced in p p Collisions at 400-GeV/c
The properties of events produced with high values of transverse energy in 400-GeV/c pp collisions are presented. The events were collected using the large-acceptance Fermilab multiparticle spectrometer. The fraction of events that are planar when a full-azimuthal-acceptance trigger is used does not increase with transverse energy. However, when additional requirements are applied to the data such as restricting the azimuth or polar-angle acceptance, limiting the particle multiplicity, or requiring dominance of electromagnetic or hadronic energy within an event, the fraction of planar events increases with transverse energy. None of these requirements explicitly impose planar structure and we conclude that the data show an indication for the emergence of jetlike structure. The trend of the data is consistent with the predictions of a QCD model; it cannot be described by an extrapolation of uncorrelated low-p/sub t/ phenomena.