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.
The Baikal Gigaton Volume Detector (Baikal-GVD) is a km
3
-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
χ
2
-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.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
ABSTRACT
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 ...data set 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.
Currently, the Baikal-GVD Deep Underwater Neutrino Telescope is being successfully deployed in Lake Baikal. It comprises 96 strings with 3456 optical modules. We present the status and plans for ...further deployment of the Baikal-GVD telescope and discuss the issues related to the development of the next-generation neutrino telescope in Lake Baikal.
The neutrino telescope Baikal-GVD is designed for search for high energy neutrinos whose sources are not yet reliably identified. It currently includes total of 3456 optical modules arranged on 96 ...strings, providing an effective volume of 0.6 km
for cascades with energy above 1 PeV. We discuss the first results from the partially built experiment, which is currently the largest neutrino telescope in the Northern Hemisphere and still growing up.
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.
—
Deployment of the deep-sea neutrino telescope Baikal-GVD continues in Lake Baikal. By April 2022, ten telescope clusters, which include 2880 optical modules, were put into operation. One of the ...urgent tasks of the Baikal project is to study the possibility of increasing the detection efficiency of the detector based on the experience of its operation and the results obtained with other neutrino telescopes in recent years. In this paper, the authors consider a variant of optimizing the telescope configuration by installing an additional string of optical modules between the detector clusters (external string). An experimental version of the external garland was installed in Lake Baikal in April 2022. The paper presents the results from calculations of the efficiency of registration of neutrino events for a new setup configuration, the technical implementation of the system for recording and collecting data from the external garland, and the first results of its full-scale tests in Lake Baikal.
The main goal of the Baikal-GVD deep-sea neutrino telescope is to detect high-energy neutrinos of astrophysical origin by reconstructing muon tracks or showers of particles generated in interactions ...of neutrino with water. Since 2020, Baikal-GVD has been monitoring IceCube telescope alerts about detecting neutrinos with energies of more than 100 TeV. This work presents results from searching for matches between Baikal-GVD events and IceCube neutrino alerts from September 2020 to April 2022.
Baikal-GVD is a 1 km
3
scale neutrino telescope now under construction in Lake Baikal. The sensitive volume of the detector is currently around 0.5 km
3
. Muons form through the exchange of W-bosons ...in the interaction between muon- and partial tau-neutrinos near the telescope. The muons then propagate to great distances in the lake’s water. Reconstructing their trajectory allows us to obtain the most accurate estimate of the direction of neutrinos at telescopes of this type. Angular resolution can be as good as 0.5° for fairly long muon tracks. The current state of affairs in analyzing track events at the Baikal-GVD is discussed.