A. Dolgolenko
A5083064386- Particle physics theoretical and experimental studies
- Quantum Chromodynamics and Particle Interactions
- High-Energy Particle Collisions Research
- Neutrino Physics Research
- Dark Matter and Cosmic Phenomena
- Atomic and Subatomic Physics Research
- Nuclear physics research studies
- Radiation Detection and Scintillator Technologies
- Astrophysics and Cosmic Phenomena
- Particle Detector Development and Performance
- Medical Imaging Techniques and Applications
- Nuclear Physics and Applications
- Quantum, superfluid, helium dynamics
- Particle Accelerators and Free-Electron Lasers
- Superconducting Materials and Applications
- Black Holes and Theoretical Physics
- Atomic and Molecular Physics
- Particle accelerators and beam dynamics
- Pulsars and Gravitational Waves Research
- Gamma-ray bursts and supernovae
- Radiation Therapy and Dosimetry
- Advanced NMR Techniques and Applications
- Computational Physics and Python Applications
- Inorganic Fluorides and Related Compounds
- X-ray Spectroscopy and Fluorescence Analysis
Kurchatov Institute
2015-2024
Institute for Theoretical and Experimental Physics
2014-2023
P.N. Lebedev Physical Institute of the Russian Academy of Sciences
1999
We report on a search for neutrinoless double-beta decay of $^{136}$Xe with EXO-200. No signal is observed an exposure 32.5 kg-yr, background ~1.5 x 10^{-3} /(kg yr keV) in the $\pm 1\sigma$ region interest. This sets lower limit half-life $T_{1/2}^{0\nu\beta\beta}$($^{136}$Xe) > 1.6 10$^{25}$ (90% CL), corresponding to effective Majorana masses less than 140-380 meV, depending matrix element calculation.
We observe a signal for the doubly charmed baryon Xi(+)(cc) in charged decay mode Xi(+)(cc)-->Lambda(+)(c)K-pi(+) data from SELEX, charm hadroproduction experiment at Fermilab. an excess of 15.9 events over expected background 6.1+/-0.5 events, statistical significance 6.3sigma. The observed mass this state is 3519+/-1 MeV/c(2). Gaussian width 3 MeV/c(2), consistent with resolution; its lifetime less than 33 fs 90% confidence.
A search for neutrinoless double-beta decay ($0\nu\beta\beta$) in $^{136}$Xe is performed with the full EXO-200 dataset using a deep neural network to discriminate between $0\nu\beta\beta$ and background events. Relative previous analyses, signal detection efficiency has been raised from 80.8% 96.4$\pm$3.0% energy resolution of detector at Q-value improved $\sigma/E=1.23\%$ $1.15\pm0.02\%$ upgraded detector. Accounting new data, median 90% confidence level half-life sensitivity this analysis...
Results from a search for neutrinoless double-beta decay (0νββ) of ^{136}Xe are presented using the first year data taken with upgraded EXO-200 detector. Relative to previous searches by EXO-200, energy resolution detector has been improved σ/E=1.23%, electric field in drift region raised 50%, and system suppress radon volume between cryostat lead shielding implemented. In addition, analysis techniques that improve topological discrimination 0νββ background events have developed....
We report on the measurement of γp→J/ψp cross section from E_{γ}=11.8 GeV down to threshold at 8.2 using a tagged photon beam with GlueX experiment. find that total falls toward less steeply than expected two-gluon exchange models. The differential dσ/dt has an exponential slope 1.67±0.39 GeV^{-2} 10.7 average energy. LHCb pentaquark candidates P_{c}^{+} can be produced in s channel this reaction. see no evidence for them and set model-dependent upper limits their branching fractions...
We report the observation of two-neutrino double-beta decay in Xe-136 with T_1/2 = 2.11 +- 0.04 (stat.) 0.21 (sys.) x 10^21 yr. This second order process, predicted by Standard Model, has been observed for several nuclei but not Xe-136. The rate provides new input to matrix element calculations and search more interesting neutrino-less decay, most sensitive probe existence Majorana particles measurement neutrino mass scale.
We report on an improved measurement of the $2\ensuremath{\nu}\ensuremath{\beta}\ensuremath{\beta}$ half-life ${}^{136}$Xe performed by EXO-200. The use a large and homogeneous time-projection chamber allows for precise estimate fiducial mass used measurement, resulting in small systematic uncertainty. also discuss detail data-analysis methods double-$\ensuremath{\beta}$ decay searches with EXO-200, while emphasizing those directly related to present measurement. is found be...
Abstract The nEXO neutrinoless double beta (0 νββ ) decay experiment is designed to use a time projection chamber and 5000 kg of isotopically enriched liquid xenon search for the in 136 Xe. Progress detector design, paired with higher fidelity its simulation an advanced data analysis, based on one used final results EXO-200, produce sensitivity prediction that exceeds half-life 10 28 years. Specifically, improvements have been made understanding production scintillation photons charge as...
We report the total and differential cross sections for $J/\psi$ photoproduction with large acceptance GlueX spectrometer photon beam energies from threshold at 8.2~GeV up to 11.44~GeV over full kinematic range of momentum transfer squared, $t$. Such coverage facilitates extrapolation forward ($t = 0$) point beyond physical region. The section is used by many theoretical models plays an important role in understanding its relation $J/\psi-$proton interaction. These measurements near are also...
The ionization of liquefied noble gases by radiation is known to be accompanied fluctuations much larger than predicted Poisson statistics. We have studied the both scintillation and in liquid xenon measured a strong anti-correlation between two at microscopic level, with coefficient $\ensuremath{-}0.80<{\ensuremath{\rho}}_{\mathrm{ep}}<\ensuremath{-}0.60.$ This provides direct experimental evidence that electron-ion recombination partially responsible for anomalously large same time allows...
High precision measurements of the differential cross sections for π0 photoproduction at forward angles two nuclei, 12C and 208Pb, have been performed incident photon energies 4.9-5.5 GeV to extract π0→γγ decay width. The experiment was done Jefferson Lab using Hall B tagger a high-resolution multichannel calorimeter. width extracted by fitting measured recently updated theoretical models process. resulting value is Γ(π0→γγ)=7.82±0.14(stat)±0.17(syst) eV. With 2.8% total uncertainty, this...
We report the first observation of a charm-strange meson D(+)(sJ)(2632) at mass 2632.5+/-1.7 MeV/c(2) in data from SELEX, charm hadro-production experiment E781 Fermilab. This state is seen two decay modes, D(+)(s)eta and D0K+. In mode we observe peak with 101 events over combinatoric background 54.9 2635.4+/-3.3 MeV/c(2). There corresponding 21 6.9 2631.5+/-2.0 The width this <17 90% confidence level. relative branching ratio Gamma(D0K+)/Gamma(D(+)(s)eta) 0.14+/-0.06. mechanism that keeps...
We report measurements of the photon beam asymmetry $\Sigma$ for reactions $\vec{\gamma}p\to p\pi^0$ and p\eta $ from GlueX experiment using a 9 GeV linearly-polarized, tagged incident on liquid hydrogen target in Jefferson Lab's Hall D. The asymmetries, measured as function proton momentum transfer, possess greater precision than previous $\pi^0$ are first $\eta$ this energy regime. results compared with theoretical predictions based $t$-channel, quasi-particle exchange constrain...
The GlueX experiment at Jefferson Lab ran with its first commissioning beam in late 2014 and the spring of 2015. Data were collected on both plastic liquid hydrogen targets, much detector has been commissioned. All systems are now performing or near design specifications events being fully reconstructed, including exclusive production π0, η ω mesons. Linearly-polarized photons successfully produced through coherent bremsstrahlung polarization transfer to ρ observed.
A search for Lorentz- and $CPT$-violating signals in the double beta decay spectrum of $^{136}\mathrm{Xe}$ has been performed using an exposure $100\text{ }\text{ }\mathrm{kg}\ifmmode\cdot\else\textperiodcentered\fi{}\mathrm{yr}$ with EXO-200 detector. No significant evidence spectral modification due to isotropic Lorentz-violation was found, a two-sided limit $\ensuremath{-}2.65\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}\text{...
We apply deep neural networks (DNN) to data from the EXO-200 experiment. In studied cases, DNN is able reconstruct relevant parameters—total energy and position—directly raw digitized waveforms, with minimal exceptions. For first time, developed algorithms are evaluated on real detector calibration data. The accuracy of reconstruction either reaches or exceeds what was achieved by conventional approaches over course Most existing event classification in particle physics trained Monte Carlo...
We measure for the first time differential photoproduction cross section $d\sigma/dt$ of $a_2(1320)$ meson at an average photon beam energy 8.5~GeV, using data with integrated luminosity 104~pb$^{-1}$ collected by GlueX experiment. fully reconstruct $\gamma p \to \eta\pi^0 p$ reaction and perform a partial-wave analysis in mass region amplitudes that incorporate linear polarization beam. This allows us to separate contributions natural- unnatural-parity exchanges. These measurements provide...