Abstract
In the paper we present our simulation strategy of the Tunka-Grande, TAIGA-Muon, and TAIGA-HiSCORE arrays in the light of the problem of separation astrophysical high-energy gamma rays from ...the cosmic ray background. The paper contains a description of our simulation method, based on Geant4 and CORSIKA codes. We also present the prospect of future research with TAIGA (Tunka Advanced Instrument for cosmic rays and Gamma Astronomy) with using the simulation results.
The Tunka-Grande and TAIGA-Muon arrays are the part of a single experimental complex, which also includes the Tunka-133 and TAIGA-HiSCORE (High Sensitivity COsmic Rays and gamma Explorer) wide-angle ...Cherenkov arrays, TAIGA-IACT array (Imaging Atmospheric Cherenkov Telescope) and Tunka-Rex radio antennas array (Tunka Radio Extension). This complex is located in the Tunka Valley (Buryatia Republic, Russia), 50 km from Lake Baikal. It is aimed at investigating the energy spectrum and mass composition of charged cosmic rays in the energy range 100 TeV - 1000 PeV, searching for diffuse gamma rays above 100 TeV and studying local sources of gamma rays with energies above 30 TeV. This report outlines 3 key points. The first is a description of the Tunka-Grande and TAIGA-Muon scintillation arrays. The second part presents preliminary results of the search for diffuse gamma rays with energies above 50 PeV according to the Tunka-Grande data. The third part is devoted to the prospects of the search for diffuse gamma rays with energies above 100 TeV using the TAIGA-Muon array.
The differential energy spectrum of cosmic rays in the energy range of 3 × 10
14
–3 × 10
18
eV and the corrected dependence of the mean depth of the maximum 〈
X
max
〉 of an extensive air shower (EAS) ...inside the wide energy range of 10
15
–3 × 10
17
eV have been obtained from the data of the Tunka-133 array for 7 years of operation (2009–2017) and the TAIGA-HiSCORE array for the 2019–2020 season of operation. At the extremely high energy, our results agree with the results of the Pierre Auger Observatory based on direct measurements of the maximum depth by the observation of fluorescent light from EAS. The recalculation from the 〈
X
max
〉 to the parameter
, which characterizes the average composition of the primary cosmic rays, is presented.
The Tunka-Grande scintillation array is part of the TAIGA Gamma Observatory. It is intended for investigation of energy spectrum and mass composition of primary cosmic rays in the energy range 10 ...PeV-10 EeV and the search for diffuse cosmic gamma rays. The TAIGA-HiSCORE Cherenkov array aims at observing gamma-rays with the energy from 1 TeV. TAIGA-Muon low-threshold scintillation detector array is a network of surface and underground detectors for registration charge particles of EAS. Currently, 3 clusters have been deployed. The first cluster is running in test mode. It is planed that in the future the total area of the TAIGA-Muon will be about 2000 sq. m. and it will search astrophysical gamma-rays in the energy range from 100 TeV together with the Tunka-Grande scintillation array and the Cherenkov experiments of the TAIGA Gamma Observatory. To evaluate the possibility of join operation Tunka-Grande, TAIGA-Muon and TAIGA-HiSCORE, a simulation was performed using the CORSIKA and Geant4 software packages. The status of model-based studies is presented and assessed the prospects for joint operation of the arrays.
The TAIGA-Muon scintillation array is located in the Tunka Valley. It is a part of the single TAIGA experimental complex. Its construction has started in the summer of 2019. By the autumn of 2019, ...the first three clusters were installed. We describe the design of the TAIGA-Muon array, the data acquisition (DAQ) sistem, reading and control systems.
We consider the problem of night-time atmosphere monitoring at the locations of the Yakutsk EAS array and the TAIGA observatory for the annual October-April period of observations at these ...facilities. It is shown that the use of data from instruments aboard Terra, Aqua, Suomi-NPP and NOAA-20 satellites, received by the ground stations of the Altai State University, Russia, and processed to Level 2 (retrieval of geophysical parameters of the atmosphere), gives the possibility of the near-real-time monitoring observations of the cloud cover structure and the temperature profiles at night with a spatial resolution and a frequency sufficient for meteorological correction of the detector readings.
On the basis of the scaling approach and CORSIKA simulations data the radial scale factor of the lateral distribution of electrons in extensive air showers is confirmed as a potentially effective ...primary mass estimator, and its sensitivity to hadronic interaction model is investigated. It is shown that improved composition results both on average and event-by-event basis can be achieved taking into account the universality property of air shower development expressed by the relation between the radial scale factor and the longitudinal age parameter. The enhancements of such a theoretically motivated tool for an unbiased cosmic ray composition deduction in a wide primary energy range for current and future (multi-)hybrid air shower measurements are discussed.
The astrophysical complex TAIGA (Tunka Advanced Instrument for cosmic-ray physics and Gamma-ray Astronomy), whose first phase is being completed in the Tunka valley 50 km from Lake Baikal, is ...described. Its research program, first results, and development prospects are discussed.
The possibility for a self-consistent description of all the basic features of the observed cosmic ray spectra and primary composition variations in the energy range of 1015 ÷ 1020 eV within the ...Galactic origin scenario is examined. We assume the existence of Galactic sources that accelerate particles up to ∼ 3 · 1018Z eV and take into account a highly inhomogeneous (fractal-like) distribution of matter and magnetic fields in the Galaxy that leads to extremely large free paths of particles (“Lévy flights”), along with an overwhelming contribution to the cosmic ray fluxes observed above ∼1018 eV from particles reaching the Solar System without scattering. Our scenario was refined on the basis of recent experimental results on primary mass composition. Model predictions, which could be verified with the improved high-precision measurements in the nearest future are discussed.
The sensitivity of the lateral distribution of the EAS electron component to variations in the atmospheric temperature profile is investigated. An approach developed by the authors on the basis of ...the variational theory of sensitivity is used to solve the problem. The differential sensitivity coefficients of the lateral distribution of EAS electrons to variations in the temperature profile are obtained for the first time. A method of adjusting a ground-based EAS array’s data for the temperature effect is proposed.