Scintillation detectors for the TAIGA experiment Astapov, I.; Bezyazeekov, P.; Borodin, A. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
08/2019, Letnik:
936
Journal Article
Recenzirano
It is planned that new TAIGA-Muon detectors will complement the existing Tunka-GRANDE facility of scintillation detectors of the TAIGA gamma-observatory in the Tunka valley, Russia. The new design of ...scintillation detector with wavelength shifting bars and PMTs is developed. The first prototype of the counter was installed and tested using infrastructure of the Tunka-GRANDE installation in 2017. The mass production of counters has begun in 2018 at the Novosibirsk State University.
Using methods of pulsed laser ablation from a silicon target in helium (He)-nitrogen (N
) gas mixtures maintained at reduced pressures (0.5-5 Torr), we fabricated substrate-supported silicon (Si) ...nanocrystal-based films exhibiting a strong photoluminescence (PL) emission, which depended on the He/N
ratio. We show that, in the case of ablation in pure He gas, Si nanocrystals exhibit PL bands centered in the "red - near infrared" (maximum at 760 nm) and "green" (centered at 550 nm) spectral regions, which can be attributed to quantum-confined excitonic states in small Si nanocrystals and to local electronic states in amorphous silicon suboxide (a-SiO
) coating, respectively, while the addition of N
leads to the generation of an intense "green-yellow" PL band centered at 580 nm. The origin of the latter band is attributed to a radiative recombination in amorphous oxynitride (a-SiN
O
) coating of Si nanocrystals. PL transients of Si nanocrystals with SiO
and a-SiN
O
coatings demonstrate nonexponential decays in the micro- and submicrosecond time scales with rates depending on nitrogen content in the mixture. After milling by ultrasound and dispersing in water, Si nanocrystals can be used as efficient non-toxic markers for bioimaging, while the observed spectral tailoring effect makes possible an adjustment of the PL emission of such markers to a concrete bioimaging task.
One of the most informative methods of cosmic ray studies is the detection of Cherenkov light from extensive air showers (EAS). The primary energy reconstruction is possible by using the Earth’s ...atmosphere as a huge calorimeter. The EAS Cherenkov light array Tunka-133, with ∼3 km2 geometrical area, is taking data since 2009. Tunka-133 is located in the Tunka Astrophysical Center at ∼50 km west of Lake Baikal. This array allows us to perform a detailed study of the energy spectrum and the mass composition in the energy range from 6⋅1015eV to 1018eV. Most of the ongoing efforts are focused on the construction of the first stage of the detector TAIGA (Tunka Advanced Instrument for cosmic ray physics and Gamma Astronomy). The latter is designed for the study of gamma rays and charged cosmic rays in the energy range of 1013eV–1018eV. The TAIGA prototype will consist of ∼100 wide angle timing Cherenkov stations (TAIGA-HiSCORE) and three IACTs deployed over an area of ∼1 km2. The installation of the array is planned to be finished in 2019 while the data-taking can start already during the commissioning phase. The joint reconstruction of energy, direction, and core position of the imaging and non-imaging detectors will allow us to increase the distance between the IACTs up to 800 m, therefore providing a low-cost, highly sensitive detector. The relatively low cost together with the high sensitivity for energies ≥30–50 TeV make this pioneering technique very attractive for exploring galactic PeVatrons and cosmic rays. In addition to the Cherenkov light detectors we intend to deploy surface and underground muon detectors over an area of 1 km2 with a total area of about 1000 m2. The results of the first season of coincident operation of the first ∼4 m diameter IACT with an aperture of ∼10°with 30 stations of TAIGA-HiSCORE will be presented.
The TAIGA experiment in the Tunka valley near Lake Baikal is planning an extension with new TAIGA-Muon scintillation detector stations. The main purpose of TAIGA is gamma-ray astronomy in the TeV to ...PeV energy range and cosmic ray physics. The purpose of the Taiga-Muon detectors is to measure the muon component of air showers for improving cosmic ray composition measurements as well as gamma–hadron separation above 100 TeV. Monte Carlo simulations of the experiment are done with the software packages CORSIKA and GEANT4. Extensive air showers of primary particles in the energy range 100–3000 TeV are created with CORSIKA. The trigger efficiency is calculated and used for optimization. The suppression factor of hadronic showers versus electromagnetic showers is studied, leading to an optimum depth of soil absorber (2 m), at the lowest energy range. Data on the identification efficiency for primary gamma-quanta and proton events are presented as well as the suppression factor.
TAIGA: results and perspectives Kuzmichev, L.; Astapov, I.; Bezyazeekov, P. ...
EPJ Web of Conferences,
2019, Letnik:
207
Journal Article, Conference Proceeding
Recenzirano
Odprti dostop
In this talk, we describe the status and the perspectives of the hybrid Air Shower Array TAIGA (Tunka Advanced Instrument for cosmic rays and Gamma Astronomy) which is currently under construction in ...the Tunka Valley close to Lake Baikal and is taking data in its initial configurations. TAIGA is designed for the study of gamma rays and charged cosmic rays in the energy range of 10
13
eV - 10
18
eV. It has the potential to play an important role in the search for Galactic Pevatrons and within a multi-messenger approach to explore the high-energy sky.
Electromagnetic calorimeter for Belle II Belle-ECL; Aulchenko, V; Bobrov, A ...
Journal of physics. Conference series,
01/2015, Letnik:
587, Številka:
1
Journal Article
Recenzirano
Odprti dostop
The electromagnetic calorimeter of the BELLE II detector for experiments at Super B-factory SuperKEKB is briefly described. The project of the calorimeter upgrade to meet severe background conditions ...expected at the upgraded KEK B factory is presented.
Dependence of the chemical composition of a film of plasma-chemical silicon nitride on the technological parameters of the deposition process is studied. The stages in which the process parameters ...are optimized in order to improve the masking properties of the film are described. A systematic study of the Fourier-transform infra-red (IR) spectra of plasma-chemical silicon-nitride films is carried out. It is found that the chemical resistance of a silicon-nitride film depends on the configuration in which hydrogen is incorporated into chemical bonds.
The physics motivations and advantages of the new TAIGA (Tunka Advanced Instrument for cosmic ray physics and Gamma Astronomy) detector are presented. TAIGA aims at gamma-ray astronomy at energies ...from a few TeV to several PeV, as well as cosmic ray physics from 100 TeV to several EeV. For the energy range 30 – 200 TeV the sensitivity of 10 km
2
area TAIGA array for the detection of local sources is expected to be 5 × 10
-14
erg cm
-2
sec
-1
for 300 h of observations. Reconstruction of the given EAS energy, incoming direction and its core position, based on the timing TAIGA-HiSCORE data, allows one to increase a distance between the IACTs up to 600-1000 m. The low investments together with the high sensitivity for energies ≥ 30-50 TeV make this pioneering technique very attractive for exploring the galactic PeVatrons and cosmic rays. At present the TAIGA first stage has been constructed in Tunka valley, 50 km West from the Lake Baikal. The first experimental results of the TAIGA first stage are presented.
The extensive air shower Cherenkov light array Tunka-133 collected data during 7 winter seasons from 2009 to 2017. From 2175 hours of data taking, we derived the differential energy spectrum of ...cosmic rays in the energy range 6 · 10
15
2 · 10
18
eV. The TAIGA-HiSCORE array is in the process of continuous expansion and modernization. Here we present the results obtained with 28 stations of the first HiSCORE stage from 35 clear moonless nights in the winter of 2017-2018. The combined spectrum of two arrays covers a range of 2 · 10
14
– 2 · 10
18
eV.