Dependence of the muon pseudorapidity on the cosmic ray mass composition around the knee

2014 ◽  
Vol 24 (01) ◽  
pp. 1550010 ◽  
Author(s):  
Gohar Rastegarzadeh ◽  
Mohammad Nemati

In order to identify the mass composition of cosmic rays (CRs), we have investigated the mean muon pseudorapidity (〈η〉) values of muonic component in extensive air showers (EASs). For this purpose we have simulated EASs by CORSIKA 7.4 code for Hydrogen, Oxygen and Iron nucleus. The energy range was selected between 1014 eV and 1016 eV with zenith angle from 0°–18°. We have compared our calculations with KASCADE muon tracking detector (MTD) measurements to obtain results on the primary mass relationship with mean muon pseudorapidity values of EASs muonic component. It is shown that after the knee energies, experimental data tend to the heavy primaries and mass composition becomes heavier. Finally, linear equations between the mass of primary and mean η values for different energies are obtained.

2012 ◽  
Vol 27 (39) ◽  
pp. 1230038 ◽  
Author(s):  
ALESSIO TAMBURRO

The IceCube Observatory at the South Pole is composed of a cubic kilometer scale neutrino telescope buried beneath the icecap and a square-kilometer surface water Cherenkov tank detector array known as IceTop. The combination of the surface array with the in-ice detector allows the dominantly electromagnetic signal of air showers at the surface and their high-energy muon signal in the ice to be measured in coincidence. This ratio is known to carry information about the nuclear composition of the primary cosmic rays. This paper reviews the recent results from cosmic-ray measurements performed with IceTop/IceCube: energy spectrum, mass composition, anisotropy, search for PeV γ sources, detection of high energy muons to probe the initial stages of the air shower development, and study of transient events using IceTop in scaler mode.


2019 ◽  
Vol 216 ◽  
pp. 01007 ◽  
Author(s):  
Frank G. Schröder

A surface array of radio antennas will enhance the performance of the IceTop array and enable new, complementary science goals. First, the accuracy for cosmic-ray air showers will be increased since the radio array provides a calorimetric measurement of the electromagnetic component and is sensitive to the position of the shower maximum. This enhanced accuracy can be used to better measure the mass composition, to search for possible mass-dependent anisotropies in the arrival directions of cosmic rays, and for more thorough tests of hadronic interaction models. Second, the sensitivity of the radio array to inclined showers will increase the sky coverage for cosmic-ray measurements. Third, the radio array can be used to search for PeV photons from the Galactic Center. Since IceTop is planned to be enhanced by a scintillator array in the near future, a radio extension sharing the same infrastructure can be installed with minimal additional effort and excellent scientific prospects. The combination of ice-Cherenkov, scintillation, and radio detectors at IceCube will provide unprecedented accuracy for the study of highenergy Galactic cosmic rays.


2018 ◽  
Vol 182 ◽  
pp. 02122
Author(s):  
Ryuji Takeishi

The origin of ultra-high energy cosmic rays (UHECRs) has been a longstanding mystery. The Telescope Array (TA) is the largest experiment in the northern hemisphere observing UHECR in Utah, USA. It aims to reveal the origin of UHECR by studying the energy spectrum, mass composition and anisotropy of cosmic rays. TA is a hybrid detector comprised of three air fluorescence stations which measure the fluorescence light induced from cosmic ray extensive air showers, and 507 surface scintillator counters which sample charged particles from air showers on the ground. We present the cosmic ray spectrum observed with the TA experiment. We also discuss our results from measurement of the mass composition. In addition, we present the results from the analysis of anisotropy, including the excess of observed events in a region of the northern sky at the highest energy. Finally, we introduce the TAx4 experiment which quadruples TA, and the TA low energy extension (TALE) experiment.


2019 ◽  
Vol 216 ◽  
pp. 03011
Author(s):  
I. Plaisier ◽  
A. Bonardi ◽  
S. Buitink ◽  
A. Corstanje ◽  
H. Falcke ◽  
...  

The energy and mass composition of cosmic rays influence how the energy density of the radio emission of air showers is distributed on the ground. A precise description of the radio profiles can, therefore, be used to reconstruct the properties of the primary cosmic rays. Here, such a description is presented, using a separate treatment of the two radio-emission mechanisms, the geomagnetic effect and the charge excess effect. The model is parametrized as a function that depends only on the shower parameters, allowing for a precise reconstruction of the properties of the primary cosmic rays. This model is applied to cosmic-ray events measured with LOFAR and it is capable of reconstructing the properties of air showers correctly.


2019 ◽  
Vol 216 ◽  
pp. 01005
Author(s):  
D. Kostunin ◽  
P.A. Bezyazeekov ◽  
N.M. Budnev ◽  
D. Chernykh ◽  
O. Fedorov ◽  
...  

The Tunka Radio Extension (Tunka-Rex) is a digital radio array operating in the frequency band of 30-80 MHz and detecting radio emission from air-showers produced by cosmic rays with energies above 100 PeV. The experimentis installed at the site of the TAIGA (Tunka Advanced Instrument for cosmic rays and Gamma Astronomy) observatory and performs joint measurements with the co-located particle and air-Cherenkov detectors in passive mode receiving a trigger from the latter. Tunka-Rex collects data since 2012, and during the last five years went throughseveral upgrades. As a result the density of the antenna field was increased by three times since its commission. In this contribution we present the latest results of Tunka-Rex experiment, particularly an updated analysis and efficiency study, which have been applied to the measurement of the mean shower maximum as a function of energy for cosmic rays of energies up to EeV. The future plans are also discussed: investigations towards an energy spectrum of cosmic rays with Tunka-Rex and their mass composition using a combination of Tunka-Rex data with muon measurements by the particle detector Tunka-Grande.


2019 ◽  
Vol 210 ◽  
pp. 02001
Author(s):  
Sergey Ostapchenko

The differences between contemporary Monte Carlo generators of high energy hadronic interactions are discussed and their impact on the interpretation of experimental data on ultra-high energy cosmic rays (UHECRs) is studied. Key directions for further model improvements are outlined. The prospect for a coherent interpretation of the data in terms of the UHECR composition is investigated.


2019 ◽  
Vol 210 ◽  
pp. 02012
Author(s):  
R. Takeishi

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.


2019 ◽  
Vol 210 ◽  
pp. 00001
Author(s):  
Alan Watson

The greater part of this paper is concerned with a historical discussion of the development of the search for the origins of the highest-energy cosmic-rays together with a few remarks about future prospects.Additionally, in section 6, the situation with regard to the mass composition and energy spectrum at the highest energies is discussed. It is shown that the change of the depth of shower maximum with energy above 1 EeV, measured using the Telescope Array, is in striking agreement with similar results from the Auger Observatory. This implies that either the mean mass of cosmic rays is becoming heavier above ~4 EeV or that there is a change in details of the hadronic interactions in a manner such that protons masquerade as heavier nuclei. A long-standing controversy is thus resolved: the belief that pure protons dominate the mass distribution at the highest energies is no longer tenable.


2008 ◽  
Vol 4 (S257) ◽  
pp. 471-473
Author(s):  
M. Buchvarova ◽  
P. Velinov

AbstractOur model generalizes the differential D(E) and integral D(>E) spectra of cosmic rays (CR) during the 11-year solar cycle. The empirical model takes into account galactic (GCR) and anomalous cosmic rays (ACR) heliospheric modulation by four coefficients. The calculated integral spectra in the outer planets are on the basis of mean gradients: for GCR – 3%/AU and 7%/AU for anomalous protons. The obtained integral proton spectra are compared with experimental data, the CRÈME96 model for the Earth and theoretical results of 2D stochastic model. The proposed analytical model gives practical possibility for investigation of experimental data from measurements of galactic cosmic rays and their anomalous component.


Sign in / Sign up

Export Citation Format

Share Document