arXiv subjects

A. Yakovleva

Publications and source records attributed to A. Yakovleva.

5 recordsLinked to original sources

arXiv2024

Direct determination of the $^{235}$U to $^{239}$Pu inverse beta decay yield ratio in the power reactor neutrino experiments

The yields of the inverse beta decay events produced by antineutrinos from a certain nuclear reactor fuel component are used by many experiments to check various model predictions. Yet measurements of the absolute yields feature significant uncertainties coming, mainly, from the understanding of the antineutrino detection efficiency. This work presents a simple novel approach to directly determine the $^{235}$U to $^{239}$Pu inverse beta decay yield ratio using the fuel evolution analysis. This ratio can be used for a sensitive test of reactor models, while the proposed method, results in smaller systematic uncertainties. The DANSS result on this ratio is one of the most precise among reactor neutrino experiments, yet does not significantly contradict to any previous measurement.

nucl-ex↗

arXiv2024

Long term remote reactor power and fuel composition monitoring using antineutrinos

Electron antineutrinos are emitted in the decay chains of the fission products inside a reactor core and could be used for remote monitoring of nuclear reactors. The DANSS detector is placed under the core of the 3.1 GW power reactor at the Kalinin Nuclear Power Plant (KNPP) and collects up to 5000 antineutrino events per day. DANSS measured changes of the reactor power by antineutrino counting rates over 7 years with 1.0% accuracy in one week periods. The fission fractions of four major isotopes for the reactor power calculations were provided by KNPP. The systematic uncertainty of this measurement is less than 0.8%. It is comparable to the accuracy of conventional methods of the reactor power measurements while it is based on completely different approach. For the first time the 239Pu and 235U fission fractions were reconstructed using antineutrino inverse beta-decay spectrum which is a completely new technique. This method was applied to the data from three reactor fuel campaigns (approximately 1.5 year each). The reconstructed fission fractions in about two-week measurements and the fission fractions provided by KNPP coincide within better than 3% accuracy. This provides confidence in both completely different approaches of the fission fraction determination.

hep-ex↗

arXiv2023

Study of polysterene based scintillator ageing in the DANSS experiment

DANSS is a spectrometer of reactor antineutrino based on plastic scintillator. The sensitive volume of the detector is made of 2500 polystyrene based scintillator plates with wavelength shifting (WLS) fiber readout (strips). We present a study of the strips light yield during 6.5 years of DANSS continuous running. Overall ageing at the rate $0.55 \pm 0.05(syst.)$ % per year is observed that is considerably smaller than in other similar experiments. We also observe the WLS fiber attenuation length shortening at the rate $0.26 \pm 0.04(stat.)$ % per year.

physics.ins-det↗

arXiv2023

Application of the Duperier method to the analysis of the cosmic muon flux dependence on the meteorological parameters, based on the DANSS detector data

The detector DANSS is located under n industrial nuclear reactor at Kalininskaya Nuclear Power Plant. This location provides ~ 50 m.w.e. reduction of the cosmic muon flux in the vertical direction, which places the experiment in an intermediate position between ground and underground experiments in terms of shielding from the cosmic rays. The detector DANSS is located under an industrial nuclear reactor at Kalininskaya Nuclear Power Plant. This location provides ~50 m.w.e. reduction of the cosmic muon flux in the vertical direction, which places the experiment in an intermediate position between ground and underground experiments in terms of shielding from the cosmic rays. The detector's sensitive area consists of 2500 plastic scintillator counters, each 100x4x1 cm$^3$ in size, making in total a 1 m$^3$ volume, which is surrounded by a muon veto system and multiple layers of passive shielding. The main goal of the DANSS experiment is to study the antineutrino spectra at different distances from the source. For this purpose the detector is placed on a lifting platform, and the data is collected at three positions: 10.9 m, 11.9 m and 12.9 m from the center of the reactor core. The detector is capable of reconstructing muon tracks passing though the sensitive volume. In this work the barometric, height and temperature correlation coefficients are calculated in three areas of the zenith angle $\theta$ using the Duperier approach. These results are based on the muon data collected during four years.

physics.ins-det↗

arXiv2021

Optimized scintillation strip design for the DANSS upgrade

DANSS is a one cubic meter plastic scintillator detector with a primary goal of the sterile neutrino searches at a commercial nuclear reactor. Due to its highly advantageous location, fine segmentation and ability to change the distance to the neutrino production origin DANSS is ahead of many similar experiments around the world in terms of the counting rate, signal to background ratio and sterile neutrino exclusion regions. Yet a moderate energy resolution of the detector prevents the further progress in the physics program. The main challenge of the planned upgrade is to achieve the energy resolution of 12% at 1 MeV. The new design of the main sensitive element - the plastic scintillation strip - is the most important step forward. The strip prototypes were manufactured and tested at the pion beam of the PNPI synchrocyclotron. More than twice higher light output together with fairly flat detector response uniformity, longitudinal timing information and other optimizations will surely help to reach the upgrade goal. The paper discusses the drawbacks of the current strip version, outlines the new features of the proposed upgrade, describes the beam test procedure and presents the test results reflecting the advantages of the new strip design in comparison with the currently used version.

physics.ins-det↗