12 research outputs found
Search for directional associations between Baikal Gigaton Volume Detector neutrino-induced cascades and high-energy astrophysical sources
Baikal-GVD has recently published its first measurement of the diffuse
astrophysical neutrino flux, performed using high-energy cascade-like events.
We further explore the Baikal-GVD cascade dataset collected in 2018-2022, with
the aim to identify possible associations between the Baikal-GVD neutrinos and
known astrophysical sources. We leverage the relatively high angular resolution
of the Baikal-GVD neutrino telescope (2-3 deg.), made possible by the use of
liquid water as the detection medium, enabling the study of astrophysical point
sources even with cascade events. We estimate the telescope's sensitivity in
the cascade channel for high-energy astrophysical sources and refine our
analysis prescriptions using Monte-Carlo simulations. We primarily focus on
cascades with energies exceeding 100 TeV, which we employ to search for
correlation with radio-bright blazars. Although the currently limited neutrino
sample size provides no statistically significant effects, our analysis
suggests a number of possible associations with both extragalactic and Galactic
sources. Specifically, we present an analysis of an observed triplet of
neutrino candidate events in the Galactic plane, focusing on its potential
connection with certain Galactic sources, and discuss the coincidence of
cascades with several bright and flaring blazars.Comment: 10 pages, 3 figure
Monitoring of optical properties of deep waters of Lake Baikal in 2021-2022
We present the results of the two-year (2021-2022) monitoring of absorption
and scattering lengths of light with wavelength 400-620 nm within the effective
volume of the deep underwater neutrino telescope Baikal-GVD, which were
measured by a device Baikal-5D No.2. The Baikal-5D No.2. was installed during
the 2021 winter expedition at a depth of 1180 m. The absorption and scattering
lengths were measured every week in 9 spectral points. The device Baikal-5D
No.2 also has the ability to measure detailed scattering and absorption
spectra. The data obtained make it possible to estimate the range of changes in
the absorption and scattering lengths over a sufficiently long period of time
and to investigate the relationship between the processes of changes in
absorption and scattering. An analysis was made of changes in absorption and
scattering spectra for the period 2021-2022
Large neutrino telescope Baikal-GVD: recent status
The Baikal-GVD is a deep-underwater neutrino telescope being constructed in
Lake Baikal. After the winter 2023 deployment campaign the detector consists of
3456 optical modules installed on 96 vertical strings. The status of the
detector and progress in data analysis are discussed in present report. The
Baikal-GVD data collected in 2018-2022 indicate the presence of cosmic neutrino
flux in high-energy cascade events consistent with observations by the IceCube
neutrino telescope. Analysis of track-like events results in identification of
first high-energy muon neutrino candidates. These and other results from
2018-2022 data samples are reviewed in this report
Studies of the ambient light of deep Baikal waters with Baikal-GVD
The Baikal-GVD neutrino detector is a deep-underwater neutrino telescope
under construction and recently after the winter 2023 deployment it consists of
3456 optical modules attached on 96 vertical strings. This 3-dimensional array
of photo-sensors allows to observe ambient light in the vicinity of the
Baikal-GVD telescope that is associated mostly with water luminescence. Results
on time and space variations of the luminescent activity are reviewed based on
data collected in 2018-2022
Measuring muon tracks in Baikal-GVD using a fast reconstruction algorithm
The Baikal Gigaton Volume Detector (Baikal-GVD) is a km-scale neutrino
detector currently under construction in Lake Baikal, Russia. The detector
consists of several thousand optical sensors arranged on vertical strings, with
36 sensors per string. The strings are grouped into clusters of 8 strings each.
Each cluster can operate as a stand-alone neutrino detector. The detector
layout is optimized for the measurement of astrophysical neutrinos with
energies of 100 TeV and above. Events resulting from charged current
interactions of muon (anti-)neutrinos will have a track-like topology in
Baikal-GVD. A fast -based reconstruction algorithm has been developed
to reconstruct such track-like events. The algorithm has been applied to data
collected in 2019 from the first five operational clusters of Baikal-GVD,
resulting in observations of both downgoing atmospheric muons and upgoing
atmospheric neutrinos. This serves as an important milestone towards
experimental validation of the Baikal-GVD design. The analysis is limited to
single-cluster data, favoring nearly-vertical tracks.Comment: 15 pages, 6 figures, 1 table, to be published in Eur. Phys. J.