Cosmogenic radio-nuclei are an important source of background for low-energy neutrino experiments. In Borexino, cosmogenic
11
C decays outnumber solar
pep
and CNO neutrino events by about ten to one. ...In order to extract the flux of these two neutrino species, a highly efficient identification of this background is mandatory. We present here the details of the most consolidated strategy, used throughout Borexino solar neutrino measurements. It hinges upon finding the space-time correlations between
11
C decays, the preceding parent muons and the accompanying neutrons. This article describes the working principles and evaluates the performance of this Three-Fold Coincidence (TFC) technique in its two current implementations: a hard-cut and a likelihood-based approach. Both show stable performances throughout Borexino Phases II (2012–2016) and III (2016–2020) data sets, with a
11
C tagging efficiency of
∼
90
% and
∼
63–66 % of the exposure surviving the tagging. We present also a novel technique that targets specifically
11
C produced in high-multiplicity during major spallation events. Such
11
C appear as a
burst
of events, whose space-time correlation can be exploited. Burst identification can be combined with the TFC to obtain about the same tagging efficiency of
∼
90
%
but with a higher fraction of the exposure surviving, in the range of
∼
66–68 %.
Autonomous mobile robotic system "Sesarma" Abbasov, I B; Ignatyev, V V; Orekhov, V V
IOP conference series. Materials Science and Engineering,
06/2019, Letnik:
560, Številka:
1
Journal Article
Recenzirano
Odprti dostop
The present paper is dedicated to computer modeling of the autonomous mobile robotic system. The review of publications and analogues is performed; the structure diagram and design of the developed ...robotic system are presented. The search for a robot body concept is carried out; a stage-by-stage process of its three-dimensional modeling is presented. The body lines are created using a high polygonal modeling method. The process of setting and assignment of materials based on polygonal model elements is described. A renderer is selected and light sources are installed, final scenes of scene rendering with robot are shown.
•This paper examines issues regarding computational modeling of multipurpose passenger amphibian aircraft Be-200 cabin interior.•Objects interior is designed on the basis of ergonomic principles.•For ...cabin of different variant, the scenes of realistic rendering are introduced.
This paper examines issues regarding computational modeling of multipurpose passenger amphibian aircraft Be-200 cabin interior. Here different concepts of cabin layout are introduced: economy variant; comfortable layout; with coupe-type seating; corporate variant with berths. Objects interior is designed on the basis of ergonomic principles. For cabin computational modeling the 3ds Max graphic system is used. Objects modeling is carried out by means of Spline Extrude, Polygon Extrude methods. In course of scenes shading, the materials assignment is performed at the level of subobjects. Scenes of realistic rendering of various aircraft cabin layouts are introduced.
Highly resolved multi-dimensional NOE data are essential for rapid and accurate determination of spatial protein structures such as in structural genomics projects. Four-dimensional spectra contain ...almost no spectral overlap inherently present in lower dimensionality spectra and are highly amenable to application of automated routines for spectral resonance location and assignment. However, a high resolution 4D data set using conventional uniform sampling usually requires unacceptably long measurement time. Recently we have reported that the use of non-uniform sampling and multi-dimensional decomposition (MDD) can remedy this problem. Here we validate accuracy and robustness of the method, and demonstrate its usefulness for fully protonated protein samples. The method was applied to 11 kDa protein PA1123 from structural genomics pipeline. A systematic evaluation of spectral reconstructions obtained using 15-100% subsets of the complete reference 4D 1H-13C-13C-1H NOESY spectrum has been performed. With the experimental time saving of up to six times, the resolution and the sensitivity per unit time is shown to be similar to that of the fully recorded spectrum. For the 30% data subset we demonstrate that the intensities in the reconstructed and reference 4D spectra correspond with a correlation coefficient of 0.997 in the full range of spectral amplitudes. Intensities of the strong, middle and weak cross-peaks correlate with coefficients 0.9997, 0.9965, and 0.83. The method does not produce false peaks. 2% of weak peaks lost in the 30% reconstruction is in line with theoretically expected noise increase for the shorter measurement time. Together with good accuracy in the relative line-widths these translate to reliable distance constrains derived from sparsely sampled, high resolution 4D NOESY data.
•The paper is dedicated to 3D computational modeling of amphibious aircraft Be-200.•Hereby the process of amphibious aircraft components phased modeling is presented.•Variants of shading and ...rendering of model under development are presented as well.
The paper is dedicated to 3D computational modeling of amphibious aircraft Be-200. Hereby the process of amphibious aircraft components phased modeling is presented. Variants of shading and rendering of model under development are presented as well.
We report a new technique of a multicathode counter (MCC) developed to search for hidden photon (HP) cold dark matter (CDM) with a mass from 5 to 500 eV. The method is suggested in the assumption ...that HP-photon mixing causes emission of single electrons from a metal cathode if the mass of hidden photon mγ′ is greater than a work function of the metal φW. The measured effect from HP should be dependent on φW and on the structure of electronic shells of the metal used as a cathode. Potentially this can be used for a verification of the results obtained. Some preliminary results for the upper limit for mixing parameter χ have been obtained for HP with a mass from 5 eV to 10 keV as a pure illustration of the potential of this technique. The efforts are continued to refine the procedure of data treatment and to improve the work of MCC. A new detector with a more developed design is under construction.
This work is devoted to the development of non-lithographic template methods of synthesis. These methods have a significant advantage in terms of structure formation: there is no need to design and ...produce masks, which greatly simplifies the process, and more of them can work with nonplanar substrates. The purpose of this study was to reveal the conditions for the synthesis of titanium dioxide xerogel films of different topologies as well as to develop a technique for non-lithographic template electrochemical synthesis of micron metal particles arrays and to study the structure of the resulting coatings. The films were deposited on the surface of substrates via dip coating. Specific topology of the films was achieved by template sol-gel synthesis. Their structures were analyzed by SEM and XRD. Template synthesis of metal micro particles were realized by pulsed electrochemical deposition of metals into the perforations of xerogel films. Obtained materials were analyzed by SEM and XRD; the element distribution on the surface was determined by the EDS detector of SEM. Based on the analysis results, we suggest the mechanisms of formation of the xerogel topology and proved the efficiency of pulsed electrodeposition for template synthesis of micron particles arrays.
The method of measurements is described that has been performed using a multicathode counter with an iron cathode. The aim of experiment was to search for diurnal variations of the count rate of ...single electrons emitted from the surface of the cathode by the conversion of dark photons on its surface. The results obtained during 160 days of measurements are presented.
Abstract
The Borexino detector, located at the Laboratori Nazionali del Gran Sasso in Italy, is a radiopure 280 ton liquid scintillator detector with a primary goal to measure low-energy solar ...neutrinos created in the core of the Sun. These neutrinos are a consequence of nuclear fusion reactions in the solar core where Hydrogen is burned into Helium and provide a direct probe of the energy production processes, namely the proton-proton (
pp
) chain and the Carbon-Nitrogen-Oxygen (CNO) cycle. The fusion of Hydrogen in the case of the CNO cycle, which is expected to contribute in the order of less than 1% to the total solar energy, is catalyzed by Carbon, Nitrogen, and Oxygen directly depending on the abundances of these elements in the solar core. The measurement of CNO neutrinos is challenging due to the high spectral correlation with the decay electrons of the background isotope
210
Bi and the pep solar neutrino signal. The experimental achievement of thermal stabilization of the Borexino detector after mid 2016, has opened the possibility to develop a method to constrain the
210
Bi rate through its decay daughter and α emitter
210
Po which can be identified in Borexino with an efficiency close to 100 percent on an event-by-event basis. Moreover, the flux of pep neutrinos can be constrained precisely through a global analysis of solar neutrino data which is independent of the dataset used for the CNO analysis. This conference contribution is dedicated to the first experimental evidence of neutrinos produced in the CNO fusion cycle in the Sun which is at the same time the dominant energy production mechanism in heavier stars compared to the Sun.
Concentration effects in the base-catalyzed hydrolysis of water-soluble methacrylates (3-(N,N-dimethylaminoethyl) methacrylate (DMAEMA), 2-hydroxyethyl methacrylate (HEMA) and oligo(ethylene glycol) ...methacrylates (OEGMAs)) have been studied. These monomers are rapidly hydrolyzed in the presence of bases at the room temperature in dilute aqueous solutions, but the reaction rate decreases sharply in highly concentrated solutions. A clear correlation was found between a form of the viscosity isotherm for DMAEMA solutions and the concentration dependence of the autocatalytic hydrolysis rate which indicates the connection of process kinetics with the structure of solutions. These data should be considered when carrying out homo- and copolymerization of the previously mentioned monomers in aqueous solutions.
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