Problems of the development of liquid organic scintillators are discussed from the point of view of the content of radioactive impurities in detectors for recording rare events. The results of ...investigations of various methods for purifying individual scintillator components from U, Th, and K are presented. It is shown the PPO (2,5-Diphenyloxazole) scintillation additive, where the concentration of potassium may range between 0.8 and 7.1
g/g, is the main source of contamination with potassium (
K). In linear alkylbenzene (LAB, Russia), which is viewed as a promising dissolver for creating a large-scale neutrino detector, the measured concentration of potassium is about 10
g/g.
We present the status of research and development of a new highly efficient liquid scintillator based on linear alkylbenzene and organosilicon scintillation fluor, so called NOL (Nanostructured ...Organosilicon Luminophore). The measurements of the emission kinetics under irradiation by gamma-quanta and alpha-particles were performed. The results of long term stability measurements are decribed.
The article reports on the current status of the Baksan Large Neutrino Telescope project and describes some selective results of the first stage of the project, a detector prototype with a liquid ...scintillator mass of 0.5 tons. The results of the second stage of the project, a prototype with liquid scintillator mass of 5 tons, and project prospects also presented.
Current Status of the Baksan Large Neutrino Telescope Lukanov, A. D.; Voronin, D. M.; Fazliakhmetov, A. N. ...
Bulletin of the Russian Academy of Sciences. Physics,
07/2023, Letnik:
87, Številka:
7
Journal Article
Recenzirano
The current state of the Baksan Large Neutrino Telescope project is reviewed. Selected results are presented from the first stage of the project, a prototype detector with a liquid scintillator ...weighing 0.5 tons. Results from the second stage of the project, a prototype with a liquid scintillator having a mass of five tons, are described along with prospects for the project.
At the Baksan Neutrino Observatory (Institute for Nuclear Research of the Russian Academy of Sciences, Moscow) deployed in the Caucasus mountains, it is proposed to create, at a depth corresponding ...to about 4700 mwe (meter water equivalent), a large-volume neutrino detector on the basis of a liquid scintillator with a target mass of 10 kt. This article describes the current state of the first stage of the project, namely a prototype detector with a scintillator mass of 0.5 t. The design of the detector, the equipment and methods used are described.
Low-cost particulate matter (PM) sensors are increasingly used by researchers, public health agencies, and the public to measure spatial and temporal variations in air pollution, which can inform ...strategies for community air pollution reduction. While low-cost PM sensors provide a valuable measure of harmful fine particulate matter (PM2.5), a significant portion of ambient PM2.5 is typically the secondary product of air pollution emitted by varied sources outside of community boundaries. In contrast, concentrations of black carbon (BC), a component of PM2.5, are directly emitted by a few specific sources, such as diesel engines within communities. Motivated by community organizations seeking to understand persistent sources of local pollution, this study deployed a suite of custom-built BC sensors alongside a network of low-cost PM sensors for four weeks in two seasons at 50 stationary locations in the adjacent cities of Richmond, North Richmond, and San Pablo, California, east of the San Francisco Bay. Concentrations of BC varied more than PM2.5 both temporally and spatially. Monthly network-average BC was 3 × higher in winter than late spring, while PM2.5 was only 10% lower. In both seasons, average PM2.5 concentrations at two-thirds of sites were within ±10% of the network average, whereas two-thirds of sites had BC levels outside of ±10% of the network-average concentration. The most and least polluted locations were more persistent across seasons for BC than PM2.5, and the temporal dynamics of BC at these sites were similar, signifying that they are impacted by the same emission sources. Together, these spatiotemporal trends show that BC is a better indicator of the proximity and activity of local pollution sources than PM2.5. Thus, including BC in addition to PM2.5 in community monitoring networks can provide additional insights about local sources of air pollution.
Display omitted
•BC and PM sensors deployed 4 weeks in 2 seasons at 50 sites in an environmental justice community.•Greater spatiotemporal heterogeneity and location persistence of BC compared to PM2.5•BC more informative than PM2.5 of proximity and activity of local emission sources.•Recommend measuring PM2.5 plus BC for insights to community air protection plans.
The concept of the TAIGA experiment is to combine wide-angle timing and imaging Cherenkov telescopes as well as electron and muon detectors. The TAIGA facility aims at gamma-ray astrophysics at ...energies from a few TeV to several PeV and cosmic-ray physics from 100 TeV to several EeV but also pursues searches for astrophysical nanosecond transients, axion-like particles, Lorentz invariance violation and other unexpected manifestations of New Physics. TAIGA-1, a hybrid detector complex with an area of 1 km2, operating since 2021 in the Tunka valley, 50 km to the West from the southernmost tip of lake Baikal, and the plans for its upgrade are presented.
A new high light yield liquid scintillator based on linear alkylbenzene (LAB) as an organic solvent and a novel nanostructured organosilicon liminophore as a scintillation fluor has been developed ...for the next generation large-scale experiments in astroparticle physics. It is shown that the developed liquid scintillator has light yield almost two times higher than traditional LAB-based liquid scintillator with PPO fluor, when peak light yield values are compared, since the former peaks at 490 nm, while the latter peaks at 360 nm. At the same time light emission kinetics is characterized by about 10 ns decay time constant for its fastest component which contributes more than 80% to the total light yield of the scintillator.
Status and First Results of TAIGA Tluczykont, M.; Astapov, I. I.; Awad, A. K. ...
Physics of atomic nuclei,
11/2021, Letnik:
84, Številka:
6
Journal Article
Recenzirano
The Tunka Advanced Instrument for Gamma-ray and cosmic ray Astrophysics (TAIGA) is a hybrid experiment for the measurement of Extensive Air Showers (EAS) with good spectral resolution in the TeV to ...PeV energy range. In this domain, the long-sought Pevatrons can be detected. Currently the TAIGA detector complex combines a two wide angle shower front Cherenkov light sampling timing arrays (HiSCORE and Tunka-133), two 4 m class, 10
aperture Imaging Air Cherenkov Telescopes (IACTs) and 240 m
surface and underground charged particle detector stations. Our goal is to introduce a new hybrid reconstruction technique, combining the good angular and shower core resolution of HiSCORE with the gamma-hadron separation power of imaging air Cherenkov telescopes. This approach allows to maximize the effective area and simultaneously to reach a good gamma-hadron separation at low energies (few teraelectronvolts). At higher energies, muon detectors are planned to enhance gamma-hadron separation. During the commissioning phase of the first and second IACT, several sources were observed. First detections of known sources with the first telescope show the functionality of the TAIGA IACTs. Here, the status of the TAIGA experiment will be presented, along with first results from the current configuration.
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