相关论文: Cosmic ray air showers from sphalerons

The origin and nature of the cosmic rays is still uncertain. However, a big progress has been achieved in recent years due to the good quality data provided by current and recent cosmic-rays observatories. The cosmic ray flux decreases very…

Measurements of air showers are accumulating at an increasing rate while construction proceeds at the Pierre Auger Observatory. Although the southern site is only half complete, the cumulative exposure is already similar to those achieved…

The energy spectrum of muons produced in air showers depends not only on the properties of the primary particle, but also on the atmosphere. This is because of the competition between decay and interaction of the parent mesons, which…

Studies of the influence of different hadronic models on extensive air showers at ultra-high energies are presented. The hadronic models considered are those implemented in the well-known QGSJET and SIBYLL event generators. The different…

Extraterrestrial neutrinos can initiate deeply developing air showers, and those that traverse the atmosphere unscathed may produce cascades in the ice or water. Up to now, no such events have been observed. This can be translated into…

The combination of fluorescence and surface detectors at the Pierre Auger Observatory offers unprecedented precision in testing models of hadronic interactions at center-of-mass energies around 70 TeV and beyond. However, for some time,…

Contemporary models of hadronic interactions are reviewed. Basic phenomenological approaches are compared, with an emphasizes on the predicted air shower characteristics. Special attention is payed to the remaining discrepancies between…

Observations of cosmic rays have been improving at all energies, with higher statistics and reduced systematics. Fundamental questions remain regarding the origins of cosmic rays both within the Galaxy and in extragalactic sources, and new…

Models of electroweak symmetry breaking with more than a single doublet of Higgs scalars contain a neutral pseudoscalar boson. The production of such a pseudoscalar in hadron collisions proceeds primarily via gluon fusion through a…

The NA61/SHINE experiment at the SPS accelerator at CERN is a unique facility for the study of hadronic interactions at fixed target energies. The data collected with NA61/SHINE is relevant for a broad range of topics in cosmic-ray physics…

The energy spectrum of muons at ground level in air showers are studied and a new observable is proposed to constrain hadronic interaction models used in air shower simulations. An asymmetric Gaussian function is proposed to describe the…

Cosmic ray air showers have been known for over 30 years to emit pulsed radio emission in the frequency range from a few to a few hundred MHz, an effect that offers great opportunities for the study of extensive air showers with upcoming…

Although recent measurements of the shower profiles of ultra-high energy cosmic rays suggest that they are largely initiated by heavy nuclei, such conclusions rely on hadronic interaction models which have large uncertainties. We…

Stable Superstring Relics (SSR) provide some of the candidates for the possible origin of the Ultra High Energy Cosmic Rays (UHECR). After a brief overview of the motivations for introducing such relics, we address the question whether…

Muons serve as the best probes of the physics of hadronic interactions in the upper atmosphere because of their simple physics. All the properties of detected muons, such as their energy and angle of incidence, are governed by the…

We demonstrate that a substantial part of the present uncertainties in model predictions for the average maximum depth of cosmic ray-induced extensive air showers is related to very high energy pion-air collisions. Our analysis shows that…

Ultrahigh-energy cosmic rays are almost exclusively detected through extensive air showers, which they initiate upon interaction with the atmosphere. The longitudinal development of these air showers can be directly observed using…

The Pierre Auger Observatory has been collecting data in a stable manner since January 2004. We present here a study of the cosmic ray composition using events recorded in hybrid mode during the first years of data taking. These are air…

The effect of the geomagnetic Lorentz force on the muon component of extensive air shower (EAS) has been studied in a Monte Carlo generated simulated data sample. This geomagnetic field affects the paths of muons in an EAS, causing a local…

The Pierre Auger (cosmic ray) Observatory provides a laboratory for studying fundamental physics at energies far beyond those available at colliders. The Observatory is sensitive not only to hadrons and photons, but can in principle detect…