Related papers: Particle Physics at Ultrahigh Energies
The first interactions of photon-induced showers are of electromagnetic nature, and the transfer of energy to the hadron/muon channel is reduced with respect to the bulk of hadron-induced showers. This results in a lower number of secondary…
One of the most challenging open questions regarding the origin of ultrahigh energy cosmic rays (UHECRs) deals with the shape of the source emission spectra. A commonly-used simplifying assumption is that the source spectra of the highest…
We investigate the detection of exotic massive strongly interacting hadrons (uhecrons) in ultra high energy cosmic ray telescopes. The conclusion is that experiments such as the Pierre Auger Observatory have the potential to detect these…
The understanding of the basic properties of the ultra - high energy extensive air showers is strongly dependent on the description of the hadronic interactions in a energy range beyond that probed by the LHC. One of the uncertainties…
Ultrahigh-energy cosmic rays (UHECRs) arrive at Earth from the most energetic astrophysical accelerators in the universe. They collide with atoms in the upper atmosphere with energies about ten times higher than any man-made accelerator,…
The excess of muons observed in ultra-high-energy cosmic-ray air showers relative to simulation predictions, known as the muon puzzle, provides indirect evidence of our incomplete understanding of high-energy hadronic interactions. An…
The production at the LHC of boosted top quarks (top quarks with a transverse momentum that greatly exceeds their rest mass) is a promising process to search for phenomena beyond the Standard Model. In this contribution several examples are…
A quantitative analysis of model uncertainties for calculations of the maximum depth of proton-initiated extensive air showers (EAS) has been performed. Staying within the standard physics picture and using the conventional approach to the…
Ultra-high-energy cosmic rays (UHECRs) are the most energetic particles known - and yet their origin is still an open question. However, with the precision and accumulated statistics of the Pierre Auger Observatory and the Telescope Array,…
High energy Astroparticles include Cosmic Ray, gamma ray and neutrinos, all of them coming from the universe. The origin and production, acceleration and propagation mechanisms of ultrahigh-energy CR (up to $10^{20}$ eV) are still unknown.…
New physics beyond the electroweak scale may increase weak interaction cross sections beyond the Standard Model predictions. Such cross sections can be expected within theories that solve the hierarchy problem of known interactions with a…
The properties of cosmic rays with energies above 1PeV have to be deduced from the spacetime structure and particle content of the air showers which they initiate. In this review, a summary of the phenomenology of these giant air showers is…
Results are reported from a search for new particles that decay into a photon and two gluons, in events with jets. Novel jet substructure techniques are developed that allow photons to be identified in an environment densely populated with…
Inelastic pp collisions are dominated by soft (low momentum transfer) physics where perturbative QCD cannot be fully applied. A deep understanding of both soft and semi-hard processes is crucial for predictions of minimum bias and…
Hadron colliders at the energy frontier offer significant discovery potential through precise measurements of Standard Model processes and direct searches for new particles and interactions. A future hadron collider would enhance the…
The mass composition of ultra-high-energy cosmic rays (UHECRs) is usually inferred from the depth of the shower maximum ($X_{\rm{max}}$) of cosmic-ray showers, which is only ambiguously determined by modern hadronic interaction models. We…
We have implemented ad-hoc modifications to the CORSIKA Monte-Carlo generator which allow us to simultaneously adjust the multiplicity, elasticity and cross-section of hadronic interactions with respect to the predictions of the Sibyll 2.3d…
Ultra High Energy Cosmic Rays, UHECR, are charged particles with energies between $\sim10^{18}\,{\rm eV}$ and $\sim3\times10^{20}\,{\rm eV}\sim50\,{\rm J}$. They exhibit fundamental physics at energies inaccessible to terrestrial…
We discuss that hadron-induced atmospheric air showers from ultra-high energy cosmic rays are sensitive to QCD interactions at very small momentum fractions x where nonlinear effects should become important. The leading partons from the…
In these three lectures I discuss the present status of high-energy astroparticle physics including Ultra-High-Energy Cosmic Rays (UHECR), high-energy gamma rays, and neutrinos. The first lecture is devoted to ultra-high-energy cosmic rays.…