[en] We present a current status of the Baikal-GVD Project. The objective of this project is a construction of a km3-scale neutrino telescope in the Baikal lake. Set of prototype arrays which were installed and operated during 2009-2011 in Lake Baikal allowed to study all basic elements of the future full detector and to finalize the GVD technical design. We discuss the configuration and the design of the engineering arrays as well as DAQ performance and the preliminary results.

[en] We review the present status of the Baikal Neutrino Project and present the results obtained with the deep underwater neutrino telescope NT-200

[en] The physical motivations and advantages of the new gamma-observatory TAIGA (Tunka Advanced Instrument for cosmic ray physics and Gamma Astronomy) is presented. The TAIGA array is a complex, hybrid detector for ground-based gamma-ray astronomy for energies from a few TeV to several PeV as well as for cosmic ray studies from 100 TeV to several EeV. The TAIGA will include the wide angle Cherenkov array TAIGA-HiSCORE with ∼5 km² area, a net of 16 I ACT telescopes (with FOV of about 10x10 degree), muon detectors with a total area of up to 2000-3000 m² and the radio array Tunka-Rex. (paper)

[en] We review the present status of the Baikal Neutrino Project and present results on upward going atmospheric neutrinos, results of a search for high energy extraterrestrial neutrinos as well as preliminary results of searching for acoustic signals from EAS in water. We describe the moderate upgrade of NT-200 planned for the next years and discuss a possible detector on the Gigaton scale

[en] We review the status of the Lake Baikal Neutrino Experiment. Preparation towards a km3-scale Gigaton Volume Detector (GVD) in Lake Baikal is currently a central activity. As an important milestone, a km3-prototype string comprising 6 optical modules and based on a completely new technology, has been installed and was put into operation together with NT200+ in April, 2008. An upgraded version of the prototype string, which comprises 12 optical modules, was put into operation in April 2009. We also present new results from the long-term operation of NT200, including an improved limit on the diffuse astrophysical neutrino flux.

[en] TAIGA stands for “Tunka Advanced Instrument for cosmic ray physics and Gamma Astronomy” and is a project to build a complex, hybrid detector system for ground-based gamma- ray astronomy from a few TeV to several PeV, and for cosmic-ray studies from 100 TeV to 1 EeV. TAIGA will search for ”PeVatrons” (ultra-high energy gamma-ray sources) and measure the composition and spectrum of cosmic rays in the knee region (100 TeV - 10 PeV) with good energy resolution and high statistics. TAIGA will include Tunka-HiSCORE (an array of wide-angle air Cherenkov stations), an array of Imaging Atmospheric Cherenkov Telescopes, an array of particle detectors, both on the surface and underground, and the TUNKA-133 air Cherenkov array. (paper)

[en] The study of the cosmic ray mass composition in the energy range 10¹⁶ - 10¹⁸ eV is one of the main aims of Tunka-133. This EAS Cherenkov array started data acquisition in the Tunka Valley (50 km from Lake Baikal) in autumn 2009. Tunka-133 provides a measurement of the EAS maximum depth (X_max) with an accuracy of about 30 g/cm² . Further mass composition analyses at the highest energies (10¹⁷ - 10¹⁸ eV) will be based on the comparison of primary energy measured by the radio method and the densities of charged particles measured by shielded and unshielded detectors. The high duty cycle of the common operation of the new scintillation array (Tunka-Grande) and the radio extension of the experiment (Tunka-REX) will provide a high statistics of events. (paper)

[en] The TAIGA complex-detector is designed to study gamma and cosmic rays in the energy range above 30 TeV. We are developing a novel wide-angle imaging air Cherenkov telescope with a SiPM based camera with a field of view of 15–20${}^{\circ <!--\; ???\; -->}$ and an aperture of around 1 m${}^2$. In this report we present the design of the telescope imaging camera (optical and data acquisition systems), based on 1000–1200 SiPMs. The prototype of such camera, based on 49 SiPMs, is operating at the TAIGA's site in the Tunka valley since September 2019. The design of the prototype and the preliminary results of data analysis is presented.

[en] Measurements of optical properties in media enclosing Cherenkov neutrino telescopes are important not only at the moment of the selection of an adequate site, but also for the continuous characterization of the medium as a function of time. Over the two last decades, the Baikal collaboration has been measuring the optical properties of the deep water in Lake Baikal (Siberia) where, since April 1998, the neutrino telescope NT-200 is in operation. Measurements have been made with custom devices. The NEMO Collaboration, aiming at the construction of a km³ Cherenkov neutrino detector in the Mediterranean Sea, has developed an experimental setup for the measurement of oceanographic and optical properties of deep sea water. This setup is based on a commercial transmissometer. During a joint campaign of the two collaborations in March and April 2001, light absorption, scattering and attenuation in water have been measured. The results are compatible with previous ones reported by the Baikal Collaboration and show convincing agreement between the two experimental techniques

[en] The TAIGA observatory addresses ground-based gamma-ray astronomy at energies from a few TeV to several PeV, cosmic ray physics from 100 TeV to several EeV as well as for search for axion-like particles, Lorentz violations and another evidence of New Physics. In 2020 year a one square kilometer TAIGA setup should be put in operation.