The SND is a non-magnetic detector deployed at the VEPP-2000 e^+e^− collider (BINP, Novosibirsk) for hadronic cross-section measurements in the center of mass energy region below 2 GeV. The important ...part of the detector is a three-layer hodoscopic electromagnetic calorimeter (EMC) based on NaI(Tl) counters. Until the recent EMC spectrometric channel upgrade, only the energy deposition measurement in counters was possible. A new EMC signal shaping and digitizing electronics based on FADC allows us to obtain also the event time structure. The new electronics and supporting software, including digital signal processing algorithms, are used for data taking in the ongoing experiment. We discuss the amplitude and time extraction algorithms, the new system performance on experimental events and physical analysis applications.
The high reliability of modern 3D printing technologies makes it possible to create structural elements for aerospace and rocket industry products. Currently, the team of authors are developing a ...system for designing and additive manufacturing of composite and polymer structures for high-tech applications. In this paper, we studied the body of a Tomsk-TPU-120 CubSat satellite, the first Russian spacecraft to contain additive manufactured elements. Device quality control was carried out using resonant ultrasonic stimulation in conjunction with the use of scanning Doppler laser vibrometry, as well as experimental modal analysis. The testing results made it possible to reveal a defect at the butt end surface of the satellite body by analyzing the amplitude-frequency characteristic of surface vibrations. Experimental vibration-scanning data were used to verify a mathematical model developed using the ANSYS software.
The quality control of composite materials remains an important topic of research in nondestructive testing (NDT) of modern materials, in particular, the ones intended for aerospace industry. Over ...the last decade, there has been a noticeable increase in interest to the ultrasonic stimulation of tested materials and analysis of dynamic temperature distributions. This method is commonly implemented with two techniques, viz. high-power stimulation at a fixed acoustic-signal frequency and low-power resonant ultrasonic stimulation. Results are provided on comparing the above ultrasonic NDT methods using the example of an impact damage in a graphite epoxy-filled composite. The comparison is made based on the criteria of temperature signals, revealed flawed zone, and productivity of testing.
New results of study of e+e− annihilation to hadrons at low energies at BABAR are presented. The the cross sections for the π+π−π0π0, π+π−η final states and several exclusive hadronic modes with ...kaons are measured using the initial-state-radiation technique.
The recent precise measurements of the e+e− → K+K− and e+e− → KSKL cross sections and the hadronic spectral function of the τ− → K−KSντ decay are used to extract the isoscalar and isovector ...electromagnetic kaon form factors and their relative phase in a model independent way. The experimental results are compared with a fit based on the vector-meson-dominance model.
Current status and last results of the Spherical Neutral Detector (SND) calorimeter upgrade are described. The main part of SND detector is a three-layer spherical NaI(Tl) electromagnetic calorimeter ...(EMC). The total thickness of NaI(Tl) in the calorimeter is 35 cm. The vacuum phototriodes (VPT) are used as photosensitive devices for the calorimeter counters. The quantum efficiency of VPT is about 15%, the average gain is 10, and the light collection efficiency is about 10%. New spectrometric channel of EMC was designed and implemented. It consists of a NaI(Tl) crystal, a vacuum phototriode, a charge-sensitive preamplifier a shaper and digitizing modules. The digitization is performed by 6 ADCs AD9228BCPZ-40 (4 channel, 12 bits, 40 MBPS) and the data go in serial form to the SoC Xilinx Zynq-7000. This SoC is basically a combination of FPGA programmable logic and ARM processor. The special algorithm for signal waveform processing was developed to determine time of flight and amplitude with high time (1 ns) and amplitude (250 keV) resolution. The algorithm is based on the invariability of the signal waveform. The waveform calibration procedures are developed and implemented. Successful data taking run was performed with upgraded EMC in 2019.
We have used ISR technique to measure the proton magnetic form factor in the energy region from 3.0 to 6.5 GeV and charged kaon form factor in the range from 2.6 to 7.5 GeV. The proton data clearly ...indicate that the difference between values of time- and space-like magnetic form factors decreases with increase of energy. The kaon form factor decreases with energy faster than 1/E2, approaching the asymptotic pQCD predictions.
Coal worker’s pneumoconiosis (CWP) is an occupationally induced progressive fibrotic lung disease. This irreversible but preventable disease currently affects millions across the world, mainly in ...countries with developed coal mining industries. Here, we report a pilot study that explores the sputum microbiome as a potential non-invasive bacterial biomarker of CWP status. Sputum samples were collected from 35 former and active coal miners diagnosed with CWP and 35 healthy controls. Sequencing of bacterial 16S rRNA genes was used to study the taxonomic composition of the respiratory microbiome. There was no difference in alpha diversity between CWP and controls. The structure of bacterial communities in sputum samples (β diversity) differed significantly between cases and controls (pseudo-F = 3.61; p = 0.004). A significant increase in the abundance of Streptococcus (25.12 ± 11.37 vs. 16.85 ± 11.35%; p = 0.0003) was detected in samples from CWP subjects as compared to controls. The increased representation of Streptococcus in sputum from CWP patients was associated only with the presence of occupational pulmonary fibrosis, but did not depend on age, and did not differ between former and current miners. The study shows, for the first time, that the sputum microbiota of CWP subjects differs from that of controls. The results of our present exploratory study warrant further investigations on a larger cohort.
The paper explores how the common economic space, a product of the EU, influenced the economies of the Baltic Sea Region states in 1995—2015. The authors investigate changes in the economic ...performance of the developed (Germany, Denmark, Finland, and Sweden) and Eastern European countries (Poland, Latvia, Lithuania, Estonia) during the integration of the latter states into the EU. Performance dynamics is analyzed for eight EU Baltic Sea Region countries. Three Russian Baltic regions constitute a control group. The authors conduct a production-function-based comparative analysis of development dynamics in individual countries to identify distinctive features for each group. Despite a rapid growth of Eastern European economies, the difference between the region’s eastern and western countries remains substantial. Economic convergence between eastern and western EU countries in terms of investment does not lead to convergence in labour efficiency. The capital-labour ratio and the growth rate of labour efficiency in the Russian Baltic are close to the Eastern European average.
The cross section for the process
e
+
e
−
→
ηK
+
K
−
wasmeasured at c.m. energies in the range between 1.56 and 2.00 GeV in an experiment with the SND detector at the VEPP-2000
e
+
e
−
collider. The ...invariant-mass distribution of kaon pairs is consistent with the hypothesis that the transition through the
ηφ
intermediate state makes a dominant contribution to the transition in question.
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