Related papers: A Likelihood Method for Measuring the Ultrahigh En…
The atmospheric depth where the energy deposit profile of secondary particles from extensive air showers (EAS) reaches its maximum, $X_{\rm max}$, is related to the primary particle mass. The mass composition of the ultra-high energy cosmic…
We report a measurement of the flux of cosmic rays with unprecedented precision and statistics using data from the Pierre Auger Observatory. Based on fluorescence observations in coincidence with at least one station of the surface detector…
A common problem in ultra-high energy cosmic ray physics is the comparison of energy spectra. The question is whether the spectra from two experiments or two regions of the sky agree within their statistical and systematic uncertainties. We…
The fluxes of electrons, positrons, gammas, Cherenkov photons and muons in individual extensive air showers induced by the primary protons and helium, oxygen and iron nuclei at the level of observation have been estimated with help of the…
A key assumption in the reconstruction of extensive air showers using the air fluorescence technique is the hypothesis that fluorescence is proportional to energy deposition at all depths in the shower. This ansatz, along with the…
Theoretical predictions for lateral distribution function of electrons in extensive air showers based on scaling formalism are presented. Our results are tested by comparison with AGASA experimental data taking into account the contribution…
The Pierre Auger Observatory's (PAO) shower profile measurements can be used to constrain the chemical composition of the ultra-high energy cosmic ray (UHECR) spectrum. In particular, the PAO's measurements of the average depth of shower…
Digital radio arrays have become an effective tool to measure air showers at energies around and above 100 PeV. Compared to optical techniques, the radio technique is not restricted to clear nights. Thanks to recent progress on…
We consider a hypothetical observatory of ultra-high energy cosmic rays consisting of two surface detector arrays that measure independently electromagnetic and muon signals induced by air showers. Using the constant intensity cut method,…
The Pierre Auger Observatory (PAO) has measured the spectrum and composition of the ultrahigh energy cosmic rays with unprecedented precision. We use these measurements to constrain their spectrum and composition as injected from their…
At the Yakutsk EAS array E_em is determined by using measurements of EAS Cherenkov light flux and charged particle flux. It is known from calculations that these characteristics depend on a sort of primary particle and, therefore, the…
Using measured events from the fluorescence detector of the Pierre Auger Observatory, an unbiased distribution of the atmospheric slant depths where showers reach their maxima has been obtained. Analyzing the tail of this distribution the…
A major part of cosmic rays consists of the primary protons, and this portion plays a crucial role in the space applications such as shielding of spacecrafts. In this study, the proton flux values measured at the top of the atmosphere…
In search for new methods of determining the primary energy spectrum of Cosmic Rays, the attention was paid to the density spectrum measurement. New methods available at present warrant an accurateness of conclusions derived from the…
We present a new measurement of the antiproton to proton abundance ratio, pbar/p, in the cosmic radiation. The HEAT-pbar instrument, a balloon borne magnet spectrometer with precise rigidity and multiple energy loss measurement capability,…
The average profiles of cosmic ray shower development as a function of atmospheric depth are measured for the first time with the Fluorescence Detectors at the Pierre Auger Observatory. The profile shapes are well reproduced by the…
The energy spectrum and primary composition of cosmic rays with energy between $3\times 10^{14}$ and $3\times10^{16}\unit{eV}$ have been studied using the CASA-BLANCA detector. CASA measured the charged particle distribution of air showers,…
The mass composition of ultra-high-energy cosmic rays (UHECRs) is commonly inferred from the first two moments of the depth of shower maximum, $X_{\rm max}$, measured by fluorescence and hybrid detectors. Such analyses require fast and…
We investigate the possibility that near future observations of ultra-high-energy cosmic rays (UHECRs) can unveil their local source distribution, which reflects the observed local structures if their origins are astrophysical objects. In…
Liquid-metal jet X-ray sources promise to deliver high photon fluxes, which are unprecedented for laboratory based X-ray sources, because the regenerating liquid-metal anode is less sensitive to damage caused by an increased electron beam…