Baikal-GVD: status and prospects Avrorin, A.D.; Avrorin, A.V.; Aynutdinov, V.M. ...
EPJ Web of Conferences,
01/2018, Letnik:
191
Journal Article, Conference Proceeding
Recenzirano
Odprti dostop
Baikal-GVD is a next generation, kilometer-scale neutrino telescope under construction in Lake Baikal. It is designed to detect astrophysical neutrino fluxes at energies from a few TeV up to 100 PeV. ...GVD is formed by multi-megaton subarrays (clusters). The array construction started in 2015 by deployment of a reduced-size demonstration cluster named "Dubna" . The first cluster in it’s baseline configuration was deployed in 2016, the second in 2017 and the third in 2018. The full-scale GVD will be an array of ~10.000 light sensors with an instrumented volume about of 2 cubic km. The first phase (GVD-1) is planned to be completed by 2020-2021. It will comprise 8 clusters with 2304 light sensors in total. We describe the design of Baikal-GVD and present selected results obtained in 2015 - 2017.
For investigation of the cosmic muon scattering tomography (MST) concept at NRC ‘‘Kurchatov Institute’’—IHEP the large-scale setup has been constructed. The setup includes 8 planes (
m
each) of ...3-layer drift tube chambers, the total quantity of drift tubes is 2304. The drift tubes were filled with gas mixture Ar
7
CO
at 0.5 bar overpressure on April 2011 and the gas system was closed. Up to now the gas mixture was not refreshed but the chambers are still working. We are presenting long term observation of the drift chambers’ behavior and some performances of the setup for this long period.
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.
The design and the procedures for assembling and testing drift tubes 15 mm in diameter made of 125-µm-thick Mylar film with a double-sided aluminum coating are presented. The technology of assembling ...three-layer chambers made of such tubes with a length of up to 2.5 m intended for use in experiments at the accelerator facility at the Institute for High Energy Physics of the National Research Center Kurchatov Institute—IHEP is described. Some results obtained during detection of cosmic muon tracks in the chambers are presented.
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.
Data obtained with two detectors located at the Tunka Cosmic Ray facility are presented. The Cherenkov light array for registration of extensive air showers (EAS) Tunka-133 collected data during 5 ...winter seasons since 2009 to 2014. The differential energy spectrum of all particles and the dependence of the average maximum depth on the energy in the range of 6 · 1015−1018 eV measured for 1540 hours of observation are presented. The preliminary all particle energy spectrum by the data of Tunka-HiSCORE prototype array, installed in 2013, is presented. Some additional experiments in the Tunka Valley are briefly described.
The 10 m
muon hodoscope made of drift tubes with length of 3.7 m and diameter of 52 mm is under development and construction at the NRC Kurchatov Institute—IHEP. In total, 768 drift tubes are grouped ...into six identical multilayers, each consisting of two tube layers with parallelly placed tubes. The orientation of tubes in adjacent multilayers is orthogonal; thus, the hodoscope has six
and six
layers of tubes. The mechanical structure, on-chamber electronics, and data acquisition system are described. Expected technical characteristics and some test results are presented.
The prototyping/early construction phase of the BAIKAL-GVD project Avrorin, A.D.; Avrorin, A.V.; Aynutdinov, V.M. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
04/2014, Letnik:
742
Journal Article
Recenzirano
Odprti dostop
The prototyping phase of the BAIKAL-GVD project has been started in April 2011 with the deployment of a three string engineering array which comprises all basic elements and systems of the Gigaton ...Volume Detector (GVD) in Lake Baikal. In April 2012 the version of engineering array which comprises the first full-scale string of the GVD demonstration cluster had been deployed and operated during 2012. The first stage of the GVD-cluster which consists of three strings was deployed in April 2013. We review the prototyping phase of the BAIKAL-GVD project and describe the configuration and design of the 2013 engineering array.
A hybrid muon hodoscope for muonography of large-scale objects has been created in the Scientific and Educational Centre NEVOD (MEPhI) with the participation of the National Research Center ...“KI”–IHEP. The multichannel detecting system of the hodoscope consists of a scintillation strip detector and a detector on drift tubes and is designed to detect tracks of charged particles, mainly muons, flying through the detector volume. The drift tube detector is an important recording element of the muon hodoscope, providing high angular and spatial accuracy of muon track reconstruction. The article describes the design of the drift tube detector, the principles of operation of the readout electronics, and also provides the main technical characteristics.
Oxidative stress acts as an important mechanism of myocardial damage during ischemia/reperfusion. To consider the possibility of restoring the redox balance with the help of “indirect” antioxidant ...effects, the cardioprotective effect of inducers of the Keap1/Nrf2/ARE system was studied when modeling prolonged ischemia/reperfusion in vivo. We used the original synthetic hydrophilic monophenol sodium 3-(3'-
tert
-butyl-4'-hydroxyphenyl) propylthiosulfonate (TS-13) and reference drug
tert
-butylhydroquinone (tBHQ). Male Wistar rats received 100 mg/kg of TS-13 solution (with drinking water) or tBHQ (intraperitoneally) daily for 7 days, while animals of the comparison groups received the corresponding solvents. Local ischemia (45 min, occlusion of the left coronary artery) and reperfusion (120 min) of the heart were modeled 1 day after the last drug administration in vivo. During the entire period of ischemia and during reperfusion, an ECG was recorded; at the end of reperfusion, the heart was removed and hypoperfusion and necrosis zones were determined. Changes in the expression of
Nfe2l2
,
Nqo1
,
hmox1
,
Gstp1
,
Rela
, and
Nfkb2
gene mRNA in myocardial tissue were determined by TaqMan real-time PCR. It was found that the groups of rats treated with TS-13 and tBHQ did not differ from the corresponding control groups in terms of the size of the necrosis zone and the number of rhythm disturbances. Preliminary administration of tBHQ to animals did not change the expression of the studied genes in heart tissue after prolonged ischemia/reperfusion. The administration of TS-13 was accompanied by an increase in the content of transcripts of the gene encoding Nrf2 (by 7.64 times) and Nrf2-driven genes:
Nqo1
(6.46 times) and
Hmox1
(3.63 times);
Gstp1
,
Rela
, and
Nfkb2
gene expression did not differ from the corresponding values of the control group; compared to animals treated with tBHQ,
Nfe2l2
,
Nqo1
,
Hmox1
,
Rela
,
Nfkb2
gene expression was 16.23, 4.44, 2.68, 3.17, and 2.64 times larger, respectively. The results obtained cast doubt on the therapeutic significance of the induction of the Keap1/Nrf2/ARE system during prolonged ischemia/reperfusion of the heart.
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