The efficiency of removing U and Th from a liquid organic scintillator based on linear alkylbenzene (LAB) by stripping with a 0.02 M aqueous solution of aminomethylenediphosphonic acid and by ...sorption on aluminum oxide and silica gel was studied. A procedure was developed for purification of scintillation additives (2,5-diphenyloxazole, 2-biphenyl-5-phenyloxazole, p-terphenyl) to remove
40
K.
At the Baksan Neutrino Observatory (Institute for Nuclear Research, Russian Academy of Sciences, Moscow) deployed in the Caucasus mountains, it is proposed to create, at a depth corresponding to 4760 ...mwe, a large-volume neutrino detector on the basis of a liquid scintillator with a target mass of 10 kt. The detector in question is intended for recording natural fluxes of neutrinos whose energy may be as low as 100MeV. Neutrino fluxes from various sources are considered in the present study, and the expected effect in the proposed detector is estimated. The detector hat is being developed at the Baksan Neutrino Observatorywill become part of the world network of neutrino detectors for studying natural neutrino fluxes.
The observation of neutrinoless double beta decay would allow to shed light onto the particle nature of neutrinos. Gerda is aiming to perform a background-free search for this process using high ...purity germanium detectors enriched in 76Ge operated in liquid argon. This goal relies on the application of active background suppression techniques. A low background light instrumentation has been installed for Phase II to detect events with coincident energy deposition in the nearby liquid argon. The intended background index of ∼10−3 cts/(keV·ky·yr) has been confirmed.
First results from GERDA Phase II Agostini, M; Allardt, M; Bakalyarov, A M ...
Journal of physics. Conference series,
09/2017, Volume:
888, Issue:
1
Journal Article
Peer reviewed
Open access
Gerda is designed for a background-free search of 76Ge neutrinoless double-β decay, using bare Ge detectors in liquid Ar. The experiment was upgraded after the successful completion of Phase I to ...double the target mass and further reduce the background. Newly-designed Ge detectors were installed along with LAr scintillation sensors. Phase II of data-taking started in Dec 2015 with approximately 36 kg of Ge detectors and is currently ongoing. The first results based on 10.8 kg· yr of exposure are presented. The background goal of 10−3 cts/(keV· kg· yr) is achieved and a search for neutrinoless double-β decay is performed by combining Phase I and II data. No signal is found and a new limit is set at T 1 / 2 0 ν > 5.3 ⋅ 10 25 yr (90% C.L.).
The use of modern breeding methods, biotechnology, and molecular genetics makes it possible to identify promising accessions with specified economically important traits at early pre-breeding stages. ...The success of creating new varieties depends on the availability of unique collections of plant genetic resources, information about genomes, possibility of
in vitro
cultivation with high regenerative capacity, and practical skills and competencies in this area. One of the advanced methods for accelerating the breeding process is genome editing using the CRISPR/Cas system. This method allows the effective modification of genes in order to obtain varieties with desired traits. In 2022, a new youth laboratory of genetics, breeding, biotechnology of ornamental and berry crops was set up at VIR as part of the National Project "Science and Universities". It is noteworthy that this event coincided with the 135th anniversary of the birth of N.I. Vavilov. The work of the laboratory is aimed at obtaining lines with desired properties for the further breeding process; identifying target genes of economically important traits for obtaining new varieties, lines, and hybrids; as well as creating protocols for the accelerated reproduction of virus-free material of commercially demanded varieties oriented towards import substitution. This review discusses current trends in breeding of ornamental and berry crops: e.g., flower color change in snapdragon and peony; flower aroma improvement in rose; architectonics change in actinidia; and increase of resistance to stress factors in blackberries, strawberries, and grapes.
The Gerda experiment, located at the Laboratori Nazionali del Gran Sasso (LNGS) of INFN in Italy, searches for the neutrinoless double beta (0νββ) decay of 76Ge. Gerda Phase II is aiming to reach a ...sensitivity for the 0νββ half life of 1026 yr in ∼ 3 years of physics data taking with 100 kg·yr of exposure and a background index of ∼ 10−3 cts/(keV·kg·yr). After 6 months of acquisition a first data release with 10.8 kg·yr of exposure is performed, showing that the design background is achieved. In this work a study of the Phase II background spectrum, the main spectral structures and the background sources will be presented and discussed.
The GERDA (GERmanium Detector Array) is an experiment for the search of neutrinoless double beta decay (0νββ) in 76Ge, located at Laboratori Nazionali del Gran Sasso of INFN (Italy). GERDA operates ...bare high purity germanium detectors submersed in liquid Argon (LAr). Phase II of data-taking started in Dec 2015 and is currently ongoing. In Phase II 35 kg of germanium detectors enriched in 76Ge including thirty newly produced Broad Energy Germanium (BEGe) detectors is operating to reach an exposure of 100 kg·yr within about 3 years data taking. The design goal of Phase II is to reduce the background by one order of magnitude to get the sensitivity for T1/20ν=O(1026) yr. To achieve the necessary background reduction, the setup was complemented with LAr veto. Analysis of the background spectrum of Phase II demonstrates consistency with the background models. Furthermore 226Ra and 232Th contamination levels consistent with screening results. In the first Phase II data release we found no hint for a 0νββ decay signal and place a limit of this process T1/20ν>5.3⋅1025 yr (90% C.L., sensitivity 4.0·1025 yr). First results of GERDA Phase II will be presented.
Consideration was given to the model obeying a system of ordinary differential equations where the subsystems are systems of autonomous ordinary differential equations. If the coupling parameter
ɛ
= ...0, then the model falls apart into decoupled subsystems. For a model consisting of coupled subsystems, considered was the main mode for which the problems of oscillations, bifurcation, and stability were solved, and the results obtained before for the case of two second-order subsystems were generalized.
A setup for measuring natural-radioactivity backgrounds and ultralow concentrations of the isotope
14
C in samples of a liquid organic scintillator was created at the low-background laboratory of the ...Baksan Neutrino Observatory (Institute for Nuclear Research, Russian Academy of Sciences) at a depth of 4900 mwe. The concentration of the radiocarbon
14C
in a sample of a scintillator based on domestically produced linear alkylbenzene was measured, and it was found that
14
C/
12
C (3.3 ± 0.5) × 10
−17
.
The reflectance spectra of five near-Earth asteroids, one Mars crosser, and four classical asteroids of the main belt in the range 0.35–0.95
µ
m have been observed, calculated, and analyzed. ...Asteroids with a magnitude up to 17 were observed in 2013–2017 with a 2-m telescope with a CCD spectrograph with extremely low spectral resolution (
R
∼ 100) of the Terskol Observatory of the Institute of Astronomy of the Russian Academy of Sciences in order to determine their taxonomic types and composition. These results show that the composition of some of the studied near-Earth asteroids is heterogeneous judging by the variations in their reflectance spectra within adjacent taxonomic classes. It is notable that some of these asteroids are binary. The physical and chemical-mineralogical interpretation of reflectance spectra is presented.
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