scholarly journals Measurement of the cosmic ray spectrum and chemical composition in the 1015-1018 eV energy range

2018 ◽  
Vol 172 ◽  
pp. 07001 ◽  
Author(s):  
Andrea Chiavassa

Cosmic ray in the 1015–1018 eV energy range can only be detected with ground based experiments, sampling Extensive Air Showers (EAS) particles. The interest in this energetic interval is related to the search of the knee of the iron component of cosmic ray and to the study of the transition between galactic and extra-galactic primaries. The energy and mass calibration of these arrays can only be performed with complete EAS simulations as no sources are available for an absolute calibration. The systematic error on the energy assignment can be estimated around 30 ± 10%. The all particle spectrum measured in this energy range is more structured than previously thought, showing some faint features: a hardening slightly above 1016 eV and a steepening below 1017 eV. The studies of the primary chemical composition are quickly evolving towards the measurements of the primary spectra of different mass groups: up to now we are able to separate (on a event by event basis) light and heavy primaries. Above the knee a steepening of the heavy primary spectrum and a hardening of the light ones have been detected.

2019 ◽  
Vol 208 ◽  
pp. 14001
Author(s):  
H. León Vargas

The HAWC (High Altitude Water Cherenkov) observatory, located on the slopes of the Sierra Negra volcano in the state of Puebla, Mexico, was designed with the goal of detecting gamma-rays in the Teraelectron- volt energy range. However, most of the air showers that are detected with the observatory, with a rate of ≈ 27 kHz, are of hadronic origin. This makes that, after three years of operations, HAWC has accumulated a very large data set that allows to perform cosmic-ray analysis of high precision. The details of the observatory operation, as well as a selection of recent results in cosmic-ray physics are discussed in this work.


2015 ◽  
Vol 754-755 ◽  
pp. 807-811
Author(s):  
A.A. Al-Rubaiee ◽  
Uda Hashim ◽  
Mohd Khairuddin Md Arshad ◽  
A. Rahim Ruslinda ◽  
R.M. Ayub ◽  
...  

The simulation of Cherenkov light Lateral distribution function (LDF) in Extensive Air Showers (EAS) initiated primary particles such as primary calcium, argon, proton iron nuclei, neutron and nitrogen have been performed using CORSIKA program for conditions and configurations of Tunka133 EAS Cherenkov array. The simulation was fulfilled at the high energy range 1014-1016eV for four different zenith angles 0o, 10o, 15oand 30o. The results of the simulated Cherenkov light LDF are compared with the measurements of Tunka133 EAS array for the same particles and energy range mentioned above. This comparison may give the good ability to reconstruct the energy spectrum and mass composition of the primary cosmic ray particles in EAS. The main feature of the given approach consists of the possibility to make a library of Cherenkov light LDF samples which could be utilized for analysis of real events which can be detected with different EAS arrays and reconstruction of the primary cosmic rays energy spectrum and mass composition of EAS particles.


1981 ◽  
Vol 94 ◽  
pp. 107-108
Author(s):  
R. J. Protheroe ◽  
J. F. Ormes

The chemical composition of cosmic ray nuclei with 3≤Z≤28 between ~100 MeV/nuc and a few hundred GeV/nuc are compared with a consistent set of propagation calculations. These include the effects of spallation (energy-dependent cross sections are used), escape and ionization loss in the interstellar medium and deceleration in the solar cavity. This has enabled a consistent study of the cosmic ray pathlength distribution to be made over this entire energy range. Details of the propagation calculation are left to a forthcoming paper.


1986 ◽  
Vol 6 (4) ◽  
pp. 425-436 ◽  
Author(s):  
R.M. Jacklyn

AbstractA review is presented of the evidence for anisotropies of galactic origin in the charged cosmic ray particle intensity at median primary energies of detection in the range 1011 – 1014eV. It concerns the period from 1958, when the first substantial long-term observations at energies of solar and sidereal modulation near 1011eV commenced underground, until 1984, by which time results were available from a number of years of accurate observations with detectors of small air showers at energies near 1014eV, too high for complicating effects of solar origin to be present. There is evidence for the existence of both unidirectional and bidirectional galactic anisotropies over the whole energy range. Tentative descriptive models are discussed in relation to advances both in solar and sidereal analytical techniques and in the ability of experimenters to account for and exploit the modulating influence of the heliomagnetosphere at the lower energies of detection.


1987 ◽  
Vol 125 ◽  
pp. 554-554
Author(s):  
Shigeki Miyaji

Cosmic ray spectrum has an intensity enhancement at energy range 1014–16 eV/nuc. Recently Takahasi et al. (1986) called an attention to chemical composition there. Although the data still contain large uncertainties, they argued an overabundance of calcium at high energies (Ca/Fe ≥ 2 above 1014 eV/nucleus) and some enhancements of medium heavy nuclei (C ∼ Ar) instead of no anomalous p, He, and Fe abundances.


1988 ◽  
Vol 108 ◽  
pp. 444-445
Author(s):  
Yoshiyuki Takahashi

High energy cosmic ray spectrum has been known to have an interesting bump in the energy range 1014 − 1016 eV. Various models to explain the spectral break in this energy range have been so far proposed; which incorporate either a large-scale termination of galactic wind, shocks with greater age and spatial extent associated with hypothetical super-bubbles powered by multiple supernovae, intersection of two quantum-gravitational components, extra-galactic component, red-shift of big-bang remnant, or a proton component from pulsars. More recently, their possible origin in type-II supernovae with magnetic acceleration mechanism is proposed by considering direct observational results of chemical composition near the bump regime of cosmic ray spectrum.


2005 ◽  
Vol 20 (29) ◽  
pp. 6814-6816
Author(s):  
A. GERANIOS ◽  
E. FOKITIS ◽  
S. MALTEZOS ◽  
K. PATRINOS ◽  
A. DIMOPOULOS

Using the AIRES code, we have generated a large number of Extensive Air Showers corresponding to Ultra high energy cosmic ray gammas, protons and iron nuclei with energy range 1015 – 1022 eV. These simulations clearly show the different atmospheric depths of the Extensive Air Shower maxima in this energy range.


Sign in / Sign up

Export Citation Format

Share Document