(SVD-2 Collaboration) A. G. Afonin, E. N. Ardashev, V. F. Golovkin, S. N. Golovnya, S. A. Gorokhov, A. A. Kiryakov, A. G. Kholodenko, V. V. Konstantinov, L. L. Kurchaninov, I. S. Lobanov, E. V. Lobanova, G. A. Mitrofanov, V. S. Petrov, A. V. Pleskach, M. K. Polkovnikov, V. N. Riadovikov*, V. N. Ronzhin, V. A. Senko,N. A. Shalanda, M. M. Soldatov, Yu. P. Tsyupa, A. P. Vorobiev, V. I. Yakimchuk, and V. N. Zapolskii∗ IHEP, Protvino, Moscow region, Russia.

The results of an analysis of data from the SERP-Е-184 experiment devoted to studying mechanisms of the production of charmed particles in proton–nucleus interactions at 70 GeV and their decays are presented. The data in question were obtained upon irradiating the SVD-2 active target consisting of carbon, silicon, and lead plates with a beam of 70-GeV protons. A detailed simulation on the basis of the FRITIOF7.02 and GEANT3.21 code packages made it possible to optimize event-selection criteria and to calculate the detection efficiency for Λ c + baryons. After selecting a signal from the threebody decay of a Λ c + baryon, the inclusive cross section for its production at near-threshold energies, its lifetime, and the parameter of the A dependence of the cross section were found. The Λ c + -baryon yields are tabulated along with data from other experiments and theoretical predictions.

Data obtained with two detectors located at the Tunka Cosmic Ray facility are presented. The Cherenkov light array for registration of extensive air showers (EAS) Tunka-133 collected data during 5 winter seasons since 2009 to 2014. The differential energy spectrum of all particles and the dependence of the average maximum depth on the energy in the range of 6 · 10 15 −10 18  eV measured for 1540 hours of observation are presented.The preliminary all particle energy spectrum by the data of Tunka-HiSCORE prototype array, installed in 2013, is presented. Some additional experiments in the Tunka Valley are briefly described.

В Тункинской долине (республика Бурятия) создается широкоугольная черенковская установка Тунка-HiSCORE, являющаяся частью планируемой комплексной гамма-обсерватории TAIGA и предназначенная для проведения исследований в области гамма-астрономии высоких энергий (>30 ТэВ) и физики космических лучей. В статье приведены первые результаты работы прототипа установки зимой 2013–2014 гг., который состоял из 9 станций, расположенных на площади 0.1 км2. Приведено описание методов обработки, точности восстановления оси ливня, энергии и угла, а также полученный дифференциальный спектр всех частиц КЛ в интервале 2 · 1014 2 · 1016 эВ и его сравнение с имеющимися данными.

The Cherenkov light array for the registration of extensive air showers (EAS) Tunka-133 collected data during 5 winter seasons from 2009 to 2014. The differential energy spectrum of all particles and the dependence of the average maximum depth on the energy in the range of 6 ⋅ 1015–1018 eV measured for 1540 hours of observation are presented.

The Tunka-133 Cherenkov light array for the detection of extensive air showers (EAS) acquires data over the five winters from 2009 to 2014. The direction of arrival, the shower core coordinates on the plane of observation, the primary energy, and the depth of the shower maximum are reconstructed for each EAS. A differential all-particle energy spectrum is obtained in the energy range of 6 × 10 15 –3 × 10 18 eV over 1540 h, along with the energy dependence of the average depth of the shower maximum in the range of 6 × 10 16 –3 × 10 18 eV. Based on this dependence, the variation in the average composition of the primary cosmic rays is estimated as a function of energy.

Черенковская установка для регистрации широких атмосферных ливней (ШАЛ) Тунка-133 набирала данные в течение пяти зимних сезонов с 2009 по 2014 г. Для каждого ливня восстанавливаются направление прихода, координаты оси на плоскости наблюдения, первичная энергия, глубина максимума. Получены дифференциальный энергетический спектр всех частиц в диапазоне энергий 6 · 1015 3 · 1018 эВ за 1540 ч, зависимость средней глубины максимума от энергии в диапазоне 1016 1018 эВ. На основании этой зависимости оценено изменение среднего состава первичных космических лучей с энергией.

The Tunka-HISCORE wide-angle Cherenkov array, one part of the planned TAIGA integrated gamma observatory intended for investigations in the field of high-energy (>30 TeV) gamma-ray astronomy and cosmic-ray physics, is deployed in the Tunka Valley (Buryat Republic). The first results from operating a prototype array composed of nine stations spread over an area of ∼0.1 square kilometers during the winter of 2013–2014 are presented. Data processing techniques are described, along with data on the accuracy of reconstructing the position of a shower’s axis, energy, and angle of arrival. The differential spectrum of all cosmic-ray particles in a shower in the energy range of 2 × 10 14 to 2 × 10 16 eV is presented and compared to the available data.

With the HiSCORE (Hundred*i Square kilometer Cosmic ORigin Explorer) experiment we aim at the exploration of the accelerator sky using indirect air shower observations of cosmic rays from 100TeV to 1EeV and gamma rays above 10TeV to several PeV. In this paper the HiSCORE detector is discribed and the results of the first prototype deployment are shown. Several components are discussed like the photomultiplier tubes, the clip-sum-trigger and the DRS4 based data acquisition. We present data taken with a first prototype station in April 2012 at Tunka.

The EAS Cherenkov light array Tunka-133, with ~3km2 geometric area, is taking data since 2009. The array permits a detailed study of cosmic ray energy spectrum and mass composition in the PeV energy range. After a short description of the methods of EAS parameter reconstruction, we present the all-particle energy spectrum and results of studying CR composition, based on 3 seasons of array operation. In the last part of the paper, we discuss possible interpretations of the obtained results.

The EAS Cherenkov array Tunka-133, with about 3km2 sensitive area, has been installed in the Tunka Valley, Siberia. The accessible energy range is 1015–1018eV. In this contribution, a description of the array and main results obtained so far are presented. A current update of the array includes the deployment of scintillation stations, radio antennas, as well as optical stations. The deployments of these optical stations are the first step towards Tunka-HiSCORE, a wide-angle, large field-of-view gamma-ray telescope.