I. N. Aleksandrov
A5112734065- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Particle Detector Development and Performance
- Quantum Chromodynamics and Particle Interactions
- Dark Matter and Cosmic Phenomena
- Neutrino Physics Research
- Computational Physics and Python Applications
- Cosmology and Gravitation Theories
- Distributed and Parallel Computing Systems
- advanced mathematical theories
- Astrophysics and Cosmic Phenomena
- Radiation Detection and Scintillator Technologies
- Advanced Data Storage Technologies
- Medical Imaging Techniques and Applications
- Particle Accelerators and Free-Electron Lasers
- Atomic and Subatomic Physics Research
- Black Holes and Theoretical Physics
- Advanced Database Systems and Queries
- Statistical Distribution Estimation and Applications
- Algorithms and Data Compression
- Data Mining Algorithms and Applications
- Advanced Research in Systems and Signal Processing
- Digital Radiography and Breast Imaging
- Advanced Data Processing Techniques
- Structural Analysis of Composite Materials
Saint-Petersburg State University of Telecommunications
2025
University of Göttingen
2023-2024
European Organization for Nuclear Research
2019-2024
Atlas Scientific (United States)
2024
A. Alikhanyan National Laboratory
2024
Institute of High Energy Physics
2024
Royal Holloway University of London
2018-2023
The University of Adelaide
2018-2023
Northern Illinois University
2023
Argonne National Laboratory
2023
Combined measurements of Higgs boson production cross sections and branching fractions are presented. The combination is based on the analyses decay modes $H \to \gamma\gamma$, $ZZ^\ast$, $WW^\ast$, $\tau\tau$, $b\bar{b}$, $\mu\mu$, searches for decays into invisible final states, off-shell production. Up to $79.8$ fb$^{-1}$ proton-proton collision data collected at $\sqrt{s}=$ 13 TeV with ATLAS detector used. Results presented gluon-gluon fusion vector-boson processes, associated vector...
The observation of Higgs boson production in association with a top quark pair ($t\bar{t}H$), based on the analysis proton-proton collision data at centre-of-mass energy 13 TeV recorded ATLAS detector Large Hadron Collider, is presented. Using corresponding to integrated luminosities up 79.8 fb$^{-1}$, and considering decays into $b\bar{b}$, $WW^*$, $\tau\tau$, $\gamma\gamma$, $ZZ^*$, observed significance 5.8 standard deviations, compared an expectation 4.9 deviations. Combined $t\bar{t}H$...
This paper describes the reconstruction of electrons and photons with ATLAS detector, as employed for measurements searches exploiting complete LHC Run 2 dataset. An improved energy clustering algorithm is introduced, its implications measurement identification are discussed in detail. Corrections calibrations that affect performance, including calibration, isolation efficiencies, charge reconstructed electron candidates determined using up to 81 fb$^{-1}$ proton-proton collision data...
A search for the electroweak production of charginos and sleptons decaying into final states with two electrons or muons is presented. The analysis based on 139 fb$^{-1}$ proton-proton collisions recorded by ATLAS detector at Large Hadron Collider $\sqrt{s}=13$ TeV. Three $R$-parity-conserving scenarios where lightest neutralino supersymmetric particle are considered: chargino pairs decays via either $W$ bosons sleptons, direct slepton pairs. optimised first these scenarios, but results also...
A search for the decay of Standard Model Higgs boson into a $b\bar{b}$ pair when produced in association with $W$ or $Z$ is performed ATLAS detector. The data, corresponding to an integrated luminosity 79.8 $\mathrm{fb}^{-1}$ were collected proton-proton collisions during Run 2 Large Hadron Collider at centre-of-mass energy 13 TeV. For mass 125 GeV, excess events over expected background from other processes found observed (expected) significance 4.9 (4.3) standard deviations. combination...
Electron and photon triggers covering transverse energies from 5 GeV to several TeV are essential for the ATLAS experiment record signals a wide variety of physics: Standard Model processes searches new phenomena in both proton-proton heavy-ion collisions. To cope with fourfold increase peak LHC luminosity 2015 2018 (Run 2), 2.1$\times$10$^{34}$cm$^{-2}$s$^{-1}$, similar number interactions per beam-crossing about 60, trigger algorithms selections were optimised control rates while retaining...
A search for heavy neutral Higgs bosons and Z′ is performed using a data sample corresponding to an integrated luminosity of 36.1 fb−1 from proton-proton collisions at $$ \sqrt{s}=13 TeV recorded by the ATLAS detector LHC during 2015 2016. The resonance assumed decay τ +τ − with least one tau lepton decaying final states hadrons neutrino. in mass range 0.2-2.25 0.2-4.0 bosons. are good agreement background predicted Standard Model. results interpreted benchmark scenarios. In context hMSSM...
Properties of the Higgs boson are measured in two-photon final state using 36.1 fb$^{-1}$ proton-proton collision data recorded at $\sqrt{s} = 13$ TeV by ATLAS experiment Large Hadron Collider. Cross-section measurements for production a through gluon-gluon fusion, vector-boson and association with vector bosonor top-quark pair reported. The signal strength, defined as ratio observed to expected yield, is each these processes well inclusively. global strength measurement $0.99 \pm 0.14$...
Jet energy scale and resolution measurements with their associated uncertainties are reported for jets using 36-81 fb$^{-1}$ of proton-proton collision data a centre-of-mass $\sqrt{s}=13$ TeV collected by the ATLAS detector at LHC. Jets reconstructed two different input types: topo-clusters formed from deposits in calorimeter cells, as well an algorithmic combination charged-particle tracks those topo-clusters, referred to particle-flow reconstruction method. The anti-$k_t$ jet algorithm...
A search for the electroweak production of charginos, neutralinos and sleptons decaying into final states involving two or three electrons muons is presented. The analysis based on 36.1 fb -1 s=13 TeV proton-proton collisions recorded by ATLAS detector at Large Hadron Collider. Several scenarios simplified models are considered. These include associated next-to-lightest neutralino lightest chargino, followed their decays with leptons via either Standard Model gauge bosons; direct chargino...
A bstract An angular analysis of the decay B d 0 → K ∗ μ + − is presented, based on proton-proton collision data recorded by ATLAS experiment at LHC. The study using 20.3 fb −1 integrated luminosity collected during 2012 centre-of-mass energy $$ \sqrt{s}=8 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msqrt><mml:mi>s</mml:mi></mml:msqrt><mml:mo>=</mml:mo><mml:mn>8</mml:mn></mml:math> TeV. Measurements * longitudinal polarisation fraction and a set parameters obtained for this...
Abstract The ATLAS experiment at the Large Hadron Collider has a broad physics programme ranging from precision measurements to direct searches for new particles and interactions, requiring ever larger more accurate datasets of simulated Monte Carlo events. Detector simulation with Geant4 is but requires significant CPU resources. Over past decade, developed utilized tools that replace most CPU-intensive component simulation—the calorimeter shower simulation—with faster methods. Here,...
The flavour-tagging algorithms developed by the ATLAS Collaboration and used to analyse its dataset of $\sqrt s = 13$ TeV $pp$ collisions from Run 2 Large Hadron Collider are presented. These new tagging based on recurrent deep neural networks, their performance is evaluated in simulated collision events. developments yield considerable improvements over previous jet-flavour identification strategies. At 77% $b$-jet efficiency operating point, light-jet (charm-jet) rejection factors 170 (5)...
Many extensions of the Standard Model predict production dark matter particles at LHC. Sufficiently light may be produced in decays Higgs boson that would appear invisible to detector. This Letter presents a statistical combination searches for H $\rightarrow$ where multiple modes are considered. These performed with ATLAS detector using 139 fb$^{-1}$ proton-proton collisions centre-of-mass energy $\sqrt{s} =13$ TeV In results =7$ and 8 TeV, an upper limit on branching ratio 0.107 (0.077)...
Abstract The need for large-scale production of highly accurate simulated event samples the extensive physics programme ATLAS experiment at Large Hadron Collider motivates development new simulation techniques. Building on recent success deep learning algorithms, variational autoencoders and generative adversarial networks are investigated modelling response central region electromagnetic calorimeter to photons various energies. properties synthesised showers compared with from a full...
A search for doubly charged Higgs bosons with pairs of prompt, isolated, highly energetic leptons the same electric charge is presented. The uses a proton–proton collision data sample at centre-of-mass energy 13 TeV corresponding to 36.1 $$\text {fb}^{-1}$$ integrated luminosity recorded in 2015 and 2016 by ATLAS detector LHC. This analysis focuses on decays $$H^{\pm \pm }\rightarrow e^{\pm }e^{\pm }$$ , }\mu ^{\pm \mu fitting dilepton mass spectra several exclusive signal regions. No...
This paper presents a search for direct electroweak gaugino or gluino pair production with chargino nearly mass-degenerate stable neutralino. It is based on an integrated luminosity of 36.1 $\mathrm{fb}^{-1}$ $pp$ collisions at $\sqrt{s} = 13$ TeV collected by the ATLAS experiment LHC. The final state interest disappearing track accompanied least one jet high transverse momentum from initial-state radiation four jets decay chain. use short segments reconstructed innermost tracking layers...
A combination of the searches for pair-produced vector-like partners top and bottom quarks in various decay channels ($T$$\rightarrow$$Zt/Wb/Ht$, $B$$\rightarrow$$Zb/Wt/Hb$) is performed using 36.1 fb$^{-1}$ $pp$ collision data at $\sqrt{s}$ = 13 TeV with ATLAS detector Large Hadron Collider. The observed are found to be good agreement Standard Model background prediction all individual searches. Therefore, combined 95% confidence-level upper limits set on production cross-section a range...
A search for the decay of Standard Model Higgs boson into a $$ b\overline{b} pair when produced in association with W or Z is performed ATLAS detector. The analysed data, corresponding to an integrated luminosity 36.1 fb−1, were collected proton-proton collisions Run 2 Large Hadron Collider at centre-of-mass energy 13 TeV. Final states containing zero, one and two charged leptons (electrons muons) are considered, targeting decays → νν, ℓν ℓℓ. For mass 125 GeV, excess events over expected...
A bstract The problems of neutrino masses, matter-antimatter asymmetry, and dark matter could be successfully addressed by postulating right-handed neutrinos with Majorana masses below the electroweak scale. In this work, leptonic decays W bosons extracted from 32.9 fb − 1 to 36.1 13 TeV proton–proton collisions at LHC are used search for heavy neutral leptons (HNLs) that produced through mixing muon or electron neutrinos. is conducted using ATLAS detector in both prompt displaced decay...
A measurement of production cross sections the Higgs boson in proton-proton collisions is presented $H\ensuremath{\rightarrow}\ensuremath{\tau}\ensuremath{\tau}$ decay channel. The analysis performed using $36.1\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ data recorded by ATLAS experiment at Large Hadron Collider a center-of-mass energy $\sqrt{s}=13\text{ }\mathrm{TeV}$. All combinations leptonic ($\ensuremath{\tau}\ensuremath{\rightarrow}\ensuremath{\ell}v\overline{v}$ with...
This paper describes a measurement of the inclusive top quark pair production cross-section (σtt¯) with data sample 3.2fb−1 proton–proton collisions at centre-of-mass energy s=13TeV, collected in 2015 by ATLAS detector LHC. uses events an opposite-charge electron–muon final state. Jets containing b-quarks are tagged using algorithm based on track impact parameters and reconstructed secondary vertices. The numbers exactly one two b-tagged jets counted used to determine simultaneously σtt¯...
The mass of the Higgs boson is measured in $H\rightarrow ZZ^* \rightarrow 4\ell$ and \gamma\gamma$ decay channels with 36.1 fb$^{-1}$ proton-proton collision data from Large Hadron Collider at a centre-of-mass energy 13 TeV recorded by ATLAS detector 2015 2016. value channel $m_{H}^{ZZ^{*}} = 124.79 \pm 0.37$ GeV, while $m_{H}^{\gamma \gamma} 124.93 0.40$ GeV. Combining these results measurement based on 7 8 yields $m_H=124.97 0.24$
The coupling properties of the Higgs boson are studied in four-lepton decay channel using 36.1 fb$^{-1}$ $pp$ collision data from LHC at a centre-of-mass energy 13 TeV collected by ATLAS detector. Cross sections measured for four key production modes several exclusive regions phase space and interpreted terms modifiers. inclusive cross section times branching ratio $H \rightarrow ZZ^*$ absolute rapidity below 2.5 is to be $1.73^{+0.24}_{-0.23}$(stat.)$^{+0.10}_{-0.08}$(exp.)$\pm 0.04$(th.)...
A bstract search is conducted for new resonances decaying into a W or Z boson and 125 GeV Higgs in the $$ \nu \overline{\nu}b\overline{b} <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>ν</mml:mi> <mml:mover> <mml:mo>¯</mml:mo> </mml:mover> <mml:mi>b</mml:mi> </mml:math> , {\ell}^{\pm}\nu b\overline{b} <mml:msup> <mml:mi>ℓ</mml:mi> <mml:mo>±</mml:mo> </mml:msup> {\ell}^{+}{\ell}^{-}b\overline{b} <mml:mo>+</mml:mo> <mml:mo>−</mml:mo> final states, where ℓ ± = e μ pp...