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Konstantin Beloborodov

Bio: Konstantin Beloborodov is an academic researcher from Budker Institute of Nuclear Physics. The author has contributed to research in topics: Large Hadron Collider & Physics. The author has an hindex of 38, co-authored 302 publications receiving 5568 citations. Previous affiliations of Konstantin Beloborodov include Novosibirsk State University & University of Iowa.


Papers
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Journal ArticleDOI
Georges Aad1, Alexander Kupco1, Samuel Webb, Timo Dreyer  +2934 moreInstitutions (2)
TL;DR: Combined measurements of Higgs boson production cross sections and branching fractions arc are presented in this paper, based on the analyses of the Higgs particle decay modes H -> gamma gamma, ZZ...
Abstract: Combined measurements of Higgs boson production cross sections and branching fractions arc presented. The combination is based on the analyses of the Higgs boson decay modes H -> gamma gamma, ZZ ...

505 citations

Journal ArticleDOI
Georges Aad1, Brad Abbott2, Dale Charles Abbott3, Ovsat Abdinov4  +2934 moreInstitutions (199)
TL;DR: In this article, a search for the electroweak production of charginos and sleptons decaying into final states with two electrons or muons is presented, based on 139.fb$^{-1}$ of proton-proton collisions recorded by the ATLAS detector at the Large Hadron Collider at
Abstract: A search for the electroweak production of charginos and sleptons decaying into final states with two electrons or muons is presented. The analysis is based on 139 fb$^{-1}$ of proton–proton collisions recorded by the ATLAS detector at the Large Hadron Collider at $\sqrt{s}=13$ $\text {TeV}$. Three R-parity-conserving scenarios where the lightest neutralino is the lightest supersymmetric particle are considered: the production of chargino pairs with decays via either W bosons or sleptons, and the direct production of slepton pairs. The analysis is optimised for the first of these scenarios, but the results are also interpreted in the others. No significant deviations from the Standard Model expectations are observed and limits at 95% confidence level are set on the masses of relevant supersymmetric particles in each of the scenarios. For a massless lightest neutralino, masses up to 420 $\text {Ge}\text {V}$ are excluded for the production of the lightest-chargino pairs assuming W-boson-mediated decays and up to 1 $\text {TeV}$ for slepton-mediated decays, whereas for slepton-pair production masses up to 700 $\text {Ge}\text {V}$ are excluded assuming three generations of mass-degenerate sleptons.

272 citations

Journal ArticleDOI
Georges Aad1, Alexander Kupco2, Samuel Webb3, Timo Dreyer4  +3380 moreInstitutions (206)
TL;DR: In this article, a search for high-mass dielectron and dimuon resonances in the mass range of 250 GeV to 6 TeV was performed at the Large Hadron Collider.

248 citations

Journal ArticleDOI
Morad Aaboud, Georges Aad1, Brad Abbott2, Dale Charles Abbott3  +2936 moreInstitutions (198)
TL;DR: An exclusion limit on the H→invisible branching ratio of 0.26(0.17_{-0.05}^{+0.07}) at 95% confidence level is observed (expected) in combination with the results at sqrt[s]=7 and 8 TeV.
Abstract: Dark matter particles, if sufficiently light, may be produced in decays of the Higgs boson. This Letter presents a statistical combination of searches for H→invisible decays where H is produced according to the standard model via vector boson fusion, Z(ll)H, and W/Z(had)H, all performed with the ATLAS detector using 36.1 fb^{-1} of pp collisions at a center-of-mass energy of sqrt[s]=13 TeV at the LHC. In combination with the results at sqrt[s]=7 and 8 TeV, an exclusion limit on the H→invisible branching ratio of 0.26(0.17_{-0.05}^{+0.07}) at 95% confidence level is observed (expected).

234 citations

Journal ArticleDOI
Georges Aad1, Alexander Kupco2, Samuel Webb3, Timo Dreyer4  +2962 moreInstitutions (195)
TL;DR: In this article, an improved energy clustering algorithm is introduced, and its implications for the measurement and identification of prompt electrons and photons are discussed in detail, including corrections and calibrations that affect performance, including energy calibration, identification and isolation efficiencies.
Abstract: This paper describes the reconstruction of electrons and photons with the ATLAS detector, employed for measurements and searches exploiting the complete LHC Run 2 dataset. An improved energy clustering algorithm is introduced, and its implications for the measurement and identification of prompt electrons and photons are discussed in detail. Corrections and calibrations that affect performance, including energy calibration, identification and isolation efficiencies, and the measurement of the charge of reconstructed electron candidates are determined using up to 81 fb−1 of proton-proton collision data collected at √s=13 TeV between 2015 and 2017.

227 citations


Cited by
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Journal Article
TL;DR: The first direct detection of gravitational waves and the first observation of a binary black hole merger were reported in this paper, with a false alarm rate estimated to be less than 1 event per 203,000 years, equivalent to a significance greater than 5.1σ.
Abstract: On September 14, 2015 at 09:50:45 UTC the two detectors of the Laser Interferometer Gravitational-Wave Observatory simultaneously observed a transient gravitational-wave signal. The signal sweeps upwards in frequency from 35 to 250 Hz with a peak gravitational-wave strain of 1.0×10(-21). It matches the waveform predicted by general relativity for the inspiral and merger of a pair of black holes and the ringdown of the resulting single black hole. The signal was observed with a matched-filter signal-to-noise ratio of 24 and a false alarm rate estimated to be less than 1 event per 203,000 years, equivalent to a significance greater than 5.1σ. The source lies at a luminosity distance of 410(-180)(+160) Mpc corresponding to a redshift z=0.09(-0.04)(+0.03). In the source frame, the initial black hole masses are 36(-4)(+5)M⊙ and 29(-4)(+4)M⊙, and the final black hole mass is 62(-4)(+4)M⊙, with 3.0(-0.5)(+0.5)M⊙c(2) radiated in gravitational waves. All uncertainties define 90% credible intervals. These observations demonstrate the existence of binary stellar-mass black hole systems. This is the first direct detection of gravitational waves and the first observation of a binary black hole merger.

4,375 citations

Journal Article
TL;DR: In this paper, the ATLAS experiment is described as installed in i ts experimental cavern at point 1 at CERN and a brief overview of the expec ted performance of the detector is given.
Abstract: This paper describes the ATLAS experiment as installed in i ts experimental cavern at point 1 at CERN. It also presents a brief overview of the expec ted performance of the detector.

2,798 citations

Proceedings ArticleDOI
01 Jan 2007
TL;DR: In this paper, a preliminary set of updated NLO parton distributions and their uncertainties determined from CCFR and NuTeV dimuon cross sections are presented, along with additional jet data from HERA and the Tevatron.
Abstract: We present a preliminary set of updated NLO parton distributions. For the first time we have a quantitative extraction of the strange quark and antiquark distributions and their uncertainties determined from CCFR and NuTeV dimuon cross sections. Additional jet data from HERA and the Tevatron improve our gluon extraction. Lepton asymmetry data and neutrino structure functions improve the flavour separation, particularly constraining the down quark valence distribution.

1,288 citations

Journal ArticleDOI
TL;DR: In this article, the authors present a review of the status of the theoretical prediction and in particular discuss the role of the hadronic vacuum polarization effects and hadronic light-by-light scattering correction, including a new evaluation of the dominant pion exchange contribution.

945 citations

Journal ArticleDOI
Sergey Alekhin, Wolfgang Altmannshofer1, Takehiko Asaka2, Brian Batell3, Fedor Bezrukov4, Kyrylo Bondarenko5, Alexey Boyarsky5, Ki-Young Choi6, Cristóbal Corral7, Nathaniel Craig8, David Curtin9, Sacha Davidson10, Sacha Davidson11, André de Gouvêa12, Stefano Dell'Oro, Patrick deNiverville13, P. S. Bhupal Dev14, Herbi K. Dreiner15, Marco Drewes16, Shintaro Eijima17, Rouven Essig18, Anthony Fradette13, Björn Garbrecht16, Belen Gavela19, Gian F. Giudice3, Mark D. Goodsell20, Mark D. Goodsell21, Dmitry Gorbunov22, Stefania Gori1, Christophe Grojean23, Alberto Guffanti24, Thomas Hambye25, Steen Honoré Hansen24, Juan Carlos Helo7, Juan Carlos Helo26, Pilar Hernández27, Alejandro Ibarra16, Artem Ivashko28, Artem Ivashko5, Eder Izaguirre1, Joerg Jaeckel29, Yu Seon Jeong30, Felix Kahlhoefer, Yonatan Kahn31, Andrey Katz32, Andrey Katz3, Andrey Katz33, Choong Sun Kim30, Sergey Kovalenko7, Gordan Krnjaic1, Valery E. Lyubovitskij34, Valery E. Lyubovitskij35, Valery E. Lyubovitskij36, Simone Marcocci, Matthew McCullough3, David McKeen37, Guenakh Mitselmakher38, Sven Moch39, Rabindra N. Mohapatra9, David E. Morrissey40, Maksym Ovchynnikov28, Emmanuel A. Paschos, Apostolos Pilaftsis14, Maxim Pospelov13, Maxim Pospelov1, Mary Hall Reno41, Andreas Ringwald, Adam Ritz13, Leszek Roszkowski, Valery Rubakov, Oleg Ruchayskiy17, Oleg Ruchayskiy24, Ingo Schienbein42, Daniel Schmeier15, Kai Schmidt-Hoberg, Pedro Schwaller3, Goran Senjanovic43, Osamu Seto44, Mikhail Shaposhnikov17, Lesya Shchutska38, J. Shelton45, Robert Shrock18, Brian Shuve1, Michael Spannowsky46, Andrew Spray47, Florian Staub3, Daniel Stolarski3, Matt Strassler32, Vladimir Tello, Francesco Tramontano48, Anurag Tripathi, Sean Tulin49, Francesco Vissani, Martin Wolfgang Winkler15, Kathryn M. Zurek50, Kathryn M. Zurek51 
Perimeter Institute for Theoretical Physics1, Niigata University2, CERN3, University of Connecticut4, Leiden University5, Korea Astronomy and Space Science Institute6, Federico Santa María Technical University7, University of California, Santa Barbara8, University of Maryland, College Park9, Claude Bernard University Lyon 110, University of Lyon11, Northwestern University12, University of Victoria13, University of Manchester14, University of Bonn15, Technische Universität München16, École Polytechnique Fédérale de Lausanne17, Stony Brook University18, Autonomous University of Madrid19, University of Paris20, Centre national de la recherche scientifique21, Moscow Institute of Physics and Technology22, Autonomous University of Barcelona23, University of Copenhagen24, Université libre de Bruxelles25, University of La Serena26, University of Valencia27, Taras Shevchenko National University of Kyiv28, Heidelberg University29, Yonsei University30, Princeton University31, Harvard University32, University of Geneva33, Tomsk Polytechnic University34, Tomsk State University35, University of Tübingen36, University of Washington37, University of Florida38, University of Hamburg39, TRIUMF40, University of Iowa41, University of Grenoble42, International Centre for Theoretical Physics43, Hokkai Gakuen University44, University of Illinois at Urbana–Champaign45, Durham University46, University of Melbourne47, University of Naples Federico II48, York University49, Lawrence Berkeley National Laboratory50, University of California, Berkeley51
TL;DR: It is demonstrated that the SHiP experiment has a unique potential to discover new physics and can directly probe a number of solutions of beyond the standard model puzzles, such as neutrino masses, baryon asymmetry of the Universe, dark matter, and inflation.
Abstract: This paper describes the physics case for a new fixed target facility at CERN SPS. The SHiP (search for hidden particles) experiment is intended to hunt for new physics in the largely unexplored domain of very weakly interacting particles with masses below the Fermi scale, inaccessible to the LHC experiments, and to study tau neutrino physics. The same proton beam setup can be used later to look for decays of tau-leptons with lepton flavour number non-conservation, $\tau \to 3\mu $ and to search for weakly-interacting sub-GeV dark matter candidates. We discuss the evidence for physics beyond the standard model and describe interactions between new particles and four different portals—scalars, vectors, fermions or axion-like particles. We discuss motivations for different models, manifesting themselves via these interactions, and how they can be probed with the SHiP experiment and present several case studies. The prospects to search for relatively light SUSY and composite particles at SHiP are also discussed. We demonstrate that the SHiP experiment has a unique potential to discover new physics and can directly probe a number of solutions of beyond the standard model puzzles, such as neutrino masses, baryon asymmetry of the Universe, dark matter, and inflation.

842 citations