Projects

A project for a comprehensive study of primary cosmic rays (PCR) and their interactions at mountain heights (project "Pamir-XXI", Eastern Pamir, 4260 m above sea level) was launched within the framework of the International Research Center "Pamir-XXI", established by the Government of Russia and Tajikistan.

In the coming years, the corresponding activities of the project participants will be carried out in accordance with the Practical Action Plan ("Road Map") for joint Russian-Tajik astrophysical research and the development of high-mountain test sites in the Eastern Pamirs for 2019-2022, developed by the Ministry of Education and Science of the Russian Federation in pursuance of the instructions of the 16th of the th meeting of the Intergovernmental Commission on Economic Cooperation between the Russian Federation and the Republic of Tajikistan dated March 20, 2019.

Currently, work at LFNR in the new scientific direction "Nuclear Photonics" is being carried out in joint experiments on the basis of a femtosecond laser complex with terawatt power at the ILC of Moscow State University. M.V. Lomonosov. The key words that define the essence of this direction are new generation gamma sources, which, thanks to their unique parameters, allow solving a number of important fundamental and applied problems.

New experimental data on the excitation of spin isomers 111mCd, 113mIn, 115mIn by real and virtual photons near the threshold (in the pygmy resonance region) were obtained at the LUE-8-5 linear electron accelerator of the Institute for Nuclear Research RAS. The measurements were carried out using a low-background camera with a high-resolution germanium detector. For the first time, it has been established that, in contrast to theoretical predictions, the ratio of cross sections for excitation of nuclei by real and virtual photons drops sharply at low energies, which indicates a change in the multipolarity of photoabsorption in the pygmy resonance region. This may be due to collective excitations of nuclei of an exotic nature (toroidal, scissor, compression vibration modes) predicted within the framework of existing models.

The purpose of the experiment is to record a very specific process: the conversion of a hidden photon into an electron emitted from the surface of the metal. In this case, the target for hidden photons is the free electrons of the degenerate electron gas of the metal, and the effect is proportional to the area of the cathode. Currently, strong limitations have been obtained using detectors where the working volume is the detector volume, but the target in this case is the valence electrons of the target atoms. Obviously, these are completely different elementary processes. Currently, our detector is the only operational detector sensitive to the interaction of hidden photons with free electrons of the degenerate electron gas of a metal.

The laboratory's low-background cameras are located at depths of 660, 1000 and 5000 meters of water equivalent. Thanks to the use of ultrabasic rock - dunite and low-background concrete as protective materials, the radiation background of the uranium and thorium series in the laboratory is reduced by more than 200 times relative to the background level of the surrounding rock.

In 1995, the ANDYRCHI installation began its operation, designed to record air showers with energy greater than 1014 eV.
The installation is located on the slope of Mount Andyrchi, above the telescope, and consists of 37 standard detectors based on plastic scintillators with an area of 1 m2. The detectors are located on an area of ~ 4.5 * 104 m2 with a step of ~ 40 m. The central detector of the installation is located above the BPST, the vertical distance is ≈ 350 m.

The "CARPET" installation, which began operation in 1973, is designed to study the hard component of cosmic rays and extensive air showers, and has a continuous recording area of 200 m2. The central part of the installation and six remote points with an area of 9 square meters. m. are composed of the same standard liquid scintillation detectors as the underground scintillation telescope.

In 1978, the 3200-channel underground scintillation telescope (UST), one of the largest underground installations of that time, was launched. In the 80s - 90s, its modernization began - an additional recording layer was installed, a second line for recording events was being manufactured, construction of the ANDYRCHI installation above the telescope and a muon detector under the COVER installation were underway.

Gallium-Germanium Neutrino Telescope {GGNT} located in a specially built deep underground laboratory at the Baksan Neutrino Observatory of the INR RAS and is designed to measure the flux of solar neutrinos. Measurements of the solar neutrino flux make it possible to obtain unique information both on the occurrence of thermonuclear reactions in the central regions of the Sun and on new properties of neutrinos. GGNT is one of the deepest underground laboratories in the world.

The idea of the BEST experiment is to place a 51Cr source with an initial activity of about 3 MCi at the center of a 50-ton target of liquid gallium metal, divided into two concentric zones - an internal 8-ton volume and an external 42-ton volume. In the absence of electron neutrino transitions to sterile states with masses on the order of electron-Volts, neutrinos from the source should produce, on average, 65 71Ge atoms per day in each zone at the start of irradiation. However, if oscillations into sterile neutrinos occur, the germanium production rates in the inner and outer zones will differ. This opens up the possibility of obtaining information about the allowed regions of oscillatory parameters of transitions between active and sterile neutrinos

The launch in 2015 of the first cluster of the Baikal deep-sea neutrino telescope, Baikal-GVD [1], opened a new stage in the creation of a neutrino telescope in Lake Baikal with a volume of about 1 cubic kilometer. The research stage of developing all the elements of the telescope and its mounting unit - a cluster of 8 garlands - was completed, and the way was opened for the systematic expansion of the telescope by installing from one to two clusters per year. 5 clusters have already been put into operation in 2019 [2]

Federal State Budgetary Institution of Science
Institute of Nuclear Research of the Russian Academy of Sciences
Head Academician of the Russian Academy of Sciences Igor Ivanovich Tkachev
Moscow, Troitsk, st. Physical, ow. 27
Members of Troitsk nu-mass II experiment at 2010
The installation yielded a hitherto unsurpassed best limit on the mass of the electron neutrino:
The inspirer and founder of the experiment was Academician Vladimir Mikhailovich Lobashev.