ABSTRACT
The existence of high-energy astrophysical neutrinos has been unambiguously demonstrated, but their sources remain elusive. IceCube reported an association of a 290-TeV neutrino with a ...gamma-ray flare of TXS 0506 + 056, an active galactic nucleus with a compact radio jet pointing to us. Later, radio-bright blazars were shown to be associated with IceCube neutrino events with high statistical significance. These associations remained unconfirmed with the data of independent experiments. Here, we report on the detection of a rare neutrino event with the estimated energy of 224 ± 75 TeV from the direction of TXS 0506 + 056 by the new Baikal Gigaton Volume Detector (Baikal-GVD) in April 2021. This event is the highest energy cascade detected so far by the Baikal-GVD neutrino telescope from a direction below horizon. The result supports previous suggestions that radio blazars in general, and TXS 0506 + 056 in particular, are the sources of high-energy neutrinos, and opens up the cascade channel for the neutrino astronomy.
Deep-Underwater Cherenkov Detector in Lake Baikal Avrorin, A.V.; Avrorin, A. D.; Ayinutdinov, V. M. ...
Journal of experimental and theoretical physics,
04/2022, Letnik:
134, Številka:
4
Journal Article
Recenzirano
Neutrino telescope Baikal-CVD is a deep-underwater Cherenkov detector of elementary particles of the 1-km
3
scale, which has been developed beginning from 2016 in Lake Baikal. The telescope is ...assembled from separate blocks (clusters of optical modules), which makes it possible to perform scientific research even at early stages of its development. In the 2021 configuration, the detector contains eight clusters with 2304 optical modules in total and is the largest neutrino telescope in the Northern hemisphere. The design and main characteristics of the Baikal-GVD data acquisition system are described, the problems of deep-underwater engineering associated with the development of the detector are considered, and some physical results obtained on the facility are presented
Neutrino astronomy offers a novel view of the non-thermal Universe and is complementary to other astronomical disciplines. The field has seen rapid progress in recent years, including the first ...detection of astrophysical neutrinos in the TeV–PeV energy range by IceCube and the first identified extragalactic neutrino source (TXS 0506+056). Further discoveries are aimed for with new cubic-kilometer telescopes in the Northern Hemisphere: Baikal-GVD, in Lake Baikal, and KM3NeT-ARCA, in the Mediterranean sea. The construction of Baikal-GVD proceeds as planned; the detector currently includes over 2000 optical modules arranged on 56 strings, providing an effective volume of 0.35 km
. We review the scientific case for Baikal-GVD, the construction plan, and first results from the partially built array.
The Baikal-GVD deep underwater neutrino experiment participates in the international multi-messenger program to detect the astrophysical sources of high- and ultrahigh-energy cosmic-ray particles, ...being at the stage of array deployment and a step-by-step increase of the telescope’s effective volume to the scale of a cubic kilometer. At present, the telescope consists of seven clusters containing 2016 photodetectors. The effective volume of the detector has reached 0.35 km
for the selection of shower events from neutrino interactions in Baikal water. The experimental data have been accumulated in a continuous exposure mode since 2015, allowing a prompt data analysis and a celestial-sphere monitoring program to be implemented in real time. We discuss the structure of the data acquisition system, describe the physical event reconstruction procedure in the mode of fast response to alerts, and present the results of our analysis of nine alerts from the polar IceCube telescope from early September to late October 2020.
The effect of a pulsed (with a duration on the order of 1 ms) and of a constant external electric field on plasma-chemical processes in the lower ionosphere at altitudes of 70–100 km above the ...Earth’s surface is considered. Interest in these externally stimulated physical settings is associated with traditional radiophysical research and problems of radio-chemical atmospheric physics, which has been actively in recent years due to its various scientific and technical applications. A new page in this field of science (unlike the use of spurious radio signals) opens up the possibility of the purposeful field impact on a GPS receiver on the improvement of work and the further development of satellite navigation systems, which, undoubtedly, has not been discussed previously in the literature. In this work, on the basis of the numerical simulation, the concentrations of the main charged particles and the electron temperature in the presence of a strong external electric field have been calculated at an altitude of 100 km.
The Advanced Laser Interferometer Gravitational-Wave Observatory and Advanced Virgo observatories recently discovered gravitational waves from a binary neutron star inspiral. A short gamma-ray burst ...that followed the merger of this binary was also recorded by Fermi gamma-ray burst monitor and International Gamma-Ray Astrophysics Laboratory, indicating particle acceleration by the source. The precise location of the event was determined by optical detections of emission following the merger. We searched for high-energy neutrinos from the merger in the energy range of 1 TeV–100 PeV using the Baikal Gigaton Volume Detector. No neutrinos directionally coincident with the source were detected within ±500 s around the merger time, as well as during a 14-day period after the gravitational wave detection. We derived 90% C.L. upper limits on the neutrino fluence from GW170817 during a ±500 s window centered on the gravitational wave trigger time, and a 14-day window following the gravitational wave signal under the assumption of an
E
−2
neutrino energy spectrum.
Deep-Water Neutrino Telescope in Lake Baikal Allakhverdyan, V. A.; Avrorin, A. D.; Avrorin, A. V. ...
Physics of atomic nuclei,
12/2021, Letnik:
84, Številka:
9
Journal Article
Recenzirano
The Baikal-GVD deep-water neutrino telescope of the cubic kilometer scale, focused on research in the field of astrophysics and particle physics, is being built in Lake Baikal. As of 2021, the ...effective volume of the detector reaches 0.4 km
3
for cascades generated by high-energy astrophysical neutrinos. The paper describes the design and basic characteristics of the telescope data acquisition system, discusses some aspects of deep-water engineering related to the deployment of the detector, and presents selected results obtained with the partially complete detector.
The influence of a charged cloud the electric field on chemical processes in the air at heights of 95-100 km has been studied. Numerical simulation of the plasma at these altitudes is performed, the ...concentrations of main charged particles are determined under the conditions of the electric field created by the unipolar charge of the cloud. It is shown that the electric fields of the clouds after the discharges of linear lightning affect the electron concentration at these altitudes.
The influence of NiO addition (from 0.1 up to 3mol%) on structure and phase transformations of zinc aluminosilicate glasses nucleated by a mixture of TiO2 and ZrO2 has been studied using small angle ...X-ray scattering (SAXS), X-ray diffraction (XRD) analysis, Raman scattering and optical absorption spectroscopy. All parent glasses were X-ray amorphous and according to SAXS data inhomogeneous. Though SAXS intensity increased with increasing the NiO content in parent glasses, the distance between the inhomogeneous regions was independent of the NiO content implying that NiO does not play a role of additional nucleating agent. The processes of phase transformations were different for glasses doped with 0–0.1 and 1–3mol% NiO. In glasses containing 0–0.1mol% NiO, ZrTiO4 and Ni,Ti-doped gahnite crystals precipitated simultaneously starting from heat-treatment at above 730°C; traces of ZrO2 tetragonal crystals were found in glass-ceramics prepared at 1000–1200°C. In glasses doped with 1–3mol% NiO, metastable nickel titanate-zirconate crystals with fluorite-type structure and size of 4–5nm appeared during heat-treatments in the temperature range of 730–800°C, the fraction of this phase increased with the increase of the NiO content in the parent glass. Nickel titanate-zirconate crystals with fluorite structure decomposed during annealing at above 800°C. Ni,Ti-doped gahnite crystals precipitated starting from heat-treatment at 800°C; ZrO2 tetragonal crystals were formed at 900–1200°C.
•Zinc-aluminosilicate glass-ceramics based on Ni,Ti-doped gahnite nanosized crystals•Inhomogeneity of parent glasses according to SAXS and Raman spectroscopy•Metastable nickel titanate-zirconate nanophase with fluorite-type structure•Sequence of phase transformations in glasses doped with low and high concentrations of NiO
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