scholarly journals Exotic model of the cosmic ray spectrum

2019 ◽  
Vol 208 ◽  
pp. 02004
Author(s):  
Sergey Shaulov
Keyword(s):  
Fine Structure ◽  
Cosmic Radiation ◽  
Cosmic Ray ◽  
Tien Shan ◽  
Mass Composition ◽  
Air Showers ◽  
Emulsion Chamber ◽  
X Ray ◽  
Hadron Spectra ◽  
Primary Cosmic Radiation

A detailed study of the cores of extensive air showers (EAS) at mountain level (Tien-Shan 690 g/cm2) was carried out in the hybrid experiment HADRON. An analysis of the fine structure of the EAS spectrum in the energy region1015 - 1017 (knee) showed that there are two breaks in the spectrum. Along with the previously known break at an energy of 3 · 1015 eV, a change in the slope of the EAS spectrum is observed at an energy slightly below 1017 eV. In addition the use of a large X-ray emulsion chamber (XREC) as a detector of EAS cores allowed us to obtain several new results. An abnormal scaling violation in hadron spectra for Ne ~ 107 (E0 ~ 1016 eV) means the existence of a penetrating component of non-nuclear origin. The conclusion about the non-nuclear origin of the penetrating component in the primary radiation of CR is confirmed by the data about the excess of muons in the EAS containing hadrons of maximum energies. It is assumed that the mass composition of primary cosmic radiation varies sharply at energies of 1015 - 1016 eV, where quasi-nuclei (strangelets) appear instead of nuclei. A new model of the mass composition of cosmic rays in the region of ultrahigh energies is proposed on this basis .

Distribution of arrival times in cosmic ray showers

1978 ◽  
Vol 10 (4) ◽  
pp. 730-735
Author(s):  
H. S. Green
Keyword(s):  
Cosmic Radiation ◽  
Three Dimensional ◽  
Stochastic Theory ◽  
Cosmic Ray ◽  
Time Of Arrival ◽  
Air Showers ◽  
Actual Distribution ◽  
Arrival Times ◽  
Primary Particles ◽  
Theoretical Analyses

The theoretical analyses of the extensive air showers developing from the cosmic radiation has its origins in the work of Carlson and Oppenheimer (1937) and Bhabha and Heitler (1937), at a time when it was thought that such showers were initiated by electrons. The realization that protons and other nuclei were the primary particles led to a reformulation of the theory by Heitler and Janossy (1949), Messel and Green (1952) and others, in which the production of energetic pions and the three-dimensional development of air showers were accounted for. But as the soft (electromagnetic) component of the cosmic radiation is the most prominent feature of air showers at sea level, there has been a sustained interest in the theory of this component. Most of the more recent work, such as that by Butcher and Messel (1960) and Thielheim and Zöllner (1972) has relied on computer simulation; but this method has disadvantages in terms of accuracy and presentation of results, especially where a simultaneous analysis of the development of air showers in terms of several physical variables is required. This is so for instance when the time of arrival is one of the variables. Moyal (1956) played an important part in the analytical formulation of a stochastic theory of cosmic ray showers, with time as an explicit variable, and it is essentially this approach which will be adopted in the following. The actual distribution of arrival times is cosmic ray showers, for which results are obtained, is of current experimental interest (McDonald, Clay and Prescott (1977)).

scholarly journals INFLUENCE OF PRIMARY COSMIC RADIATION MASS COMPOSITION ON THE ESTIMATION OF EAS ENERGY

2005 ◽  
Vol 20 (29) ◽  
pp. 6897-6899 ◽  
Author(s):  
S. P. KNURENKO ◽  
A. A. IVANOV ◽  
V. A. KOLOSOV ◽  
Z. E. PETROV ◽  
I. YE. SLEPTSOV ◽  
...  
Keyword(s):  
Cosmic Radiation ◽  
Cherenkov Radiation ◽  
Charged Particles ◽  
Mass Composition ◽  
Mixed Composition ◽  
Radiation Data ◽  
Primary Particles ◽  
Primary Cosmic Radiation ◽  
Electron Photon ◽  
Photon Component

Fraction of energy, E em /E0, transferred to the electron-photon component of EAS at E0 = 1015 ± 1019 eV was estimated by using the Cherenkov radiation data and the data on charged particles obtained at the Yakutsk EAS array. The results are compared with predictions of different models for energy dissipation into the EAS electron-photon component and with calculations performed with different primary nuclei content. In the energy ranges 1015 ± 1016 eV and 1018 ± 1019 eV , the ratio E em /E0 is equal to (77 ± 2)% and (88 ± 2)%, respectively, that does not contradict to a mixed composition of primary particles in the first energy interval and purely proton composition in the second one.

scholarly journals Study of muons from ultrahigh energy cosmic ray air showers measured with the Telescope Array experiment

2019 ◽  
Vol 210 ◽  
pp. 02012
Author(s):  
R. Takeishi
Keyword(s):  
Interaction Model ◽  
Cosmic Ray ◽  
Mass Composition ◽  
Ultrahigh Energy ◽  
Air Showers ◽  
Hadronic Interaction ◽  
Telescope Array ◽  
Interaction Models ◽  
Air Shower ◽  
Number Of Particles

One of the uncertainties in ultrahigh energy cosmic ray (UHECR) observation derives from the hadronic interaction model used for air shower Monte-Carlo (MC) simulations. One may test the hadronic interaction models by comparing the measured number of muons observed at the ground from UHECR induced air showers with the MC prediction. The Telescope Array (TA) is the largest experiment in the northern hemisphere observing UHECR in Utah, USA. It aims to reveal the origin of UHECRs by studying the energy spectrum, mass composition and anisotropy of cosmic rays by utilizing an array of surface detectors (SDs) and fluorescence detectors. We studied muon densities in the UHE extensive air showers by analyzing the signal of TA SD stations for highly inclined showers. On condition that the muons contribute about 65% of the total signal, the number of particles from air showers is typically 1.88 ± 0.08 (stat.) ± 0.42 (syst.) times larger than the MC prediction with the QGSJET II-03 model for proton-induced showers. The same feature was also obtained for other hadronic interaction models, such as QGSJET II-04.

scholarly journals Methods to measure the cosmic-ray composition with the Auger Engineering Radio Array

2019 ◽  
Vol 216 ◽  
pp. 02004 ◽  
Author(s):  
Fabrizia Canfora
Keyword(s):  
Cosmic Ray ◽  
High Energy ◽  
Mass Composition ◽  
Atmospheric Depth ◽  
Ultra High Energy ◽  
Air Showers ◽  
Radio Stations ◽  
High Energy Cosmic Rays ◽  
Air Shower ◽  
Number Of Particles

The mass composition of ultra-high-energy cosmic rays plays a key role in the understanding of the origins ofthese rare particles. A composition-sensitive observable is the atmospheric depth at which the air shower reaches the maximum number of particles (Xmax). The Auger Engineering Radio Array (AERA) detects the radio emission inthe 30-80 MHz frequency band from extensive air showers with energies larger than 1017 eV. It consists of more than 150 autonomous radio stations covering an area of about 17 km2. From the distribution of signals measured by the antennas, it is possible to estimate Xmax. In this contribution three independent methods for the estimation of Xmax will be presented.

Predominantly electromagnetic air showers of energy 1014 eV to 1016 eV

1968 ◽  
Vol 46 (10) ◽  
pp. S72-S74 ◽  
Author(s):  
K. Kamata ◽  
S. Shibata ◽  
O. Saavedra ◽  
V. Domingo ◽  
K. Suga ◽  
...  
Keyword(s):  
Gamma Rays ◽  
Cosmic Radiation ◽  
Progress Report ◽  
Point Sources ◽  
Air Showers ◽  
Air Shower ◽  
Upper Limits ◽  
Primary Cosmic Radiation ◽  
Shower Array ◽  
Air Shower Array

The Chacaltaya air shower array has continued to be used for the accumulation of muon-poor air showers in an attempt to find evidence of gamma rays in the primary cosmic radiation. A progress report is given here, and some upper limits to the intensities are presented for possible point sources and for galactic and isotropic backgrounds.

Sign in / Sign up

Export Citation Format

Share Document