Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7148

Browse

Filters

2012 - 2019112020 - 202316

Settings

Department: search.filters.department.İzmir Institute of Technology. MathematicsPublisher: search.filters.publisher.Elsevier

Search Results

Now showing 1 - 10 of 27
  • Article
    Citation - WoS: 54
    Citation - Scopus: 59
    Measurement of the WZ Production Cross Section in pp Collisions at S=13 TeV
    (Elsevier, 2017) Khachatryan, V.; Sirunyan, A. M.; Tumasyan, A.; Adam, W.; Asilar, E.; Bergauer, T.; Woods, N.
    The WZ production cross section in proton-proton collisions at root s = 13 Tev is measured with the CMS experiment at the LHC using a data sample corresponding to an integrated luminosity of 2.3 fb(-1). The measurement is performed in the leptonic decay modes WZ -> lVl'l', where l,l'=e,mu. The measured cross section for the range 60<m (l'l') <120 GeV is sigma(pp -> WZ) = 39.9 +/- 3.2(stat)(2.9)(-3.1)(syst)+/- 0.4(theo)+/- 1.3(lumi)pb, consistent with the standard model prediction.
  • Article
    Arithmetic Progressions in Certain Subsets of Finite Fields
    (Elsevier, 2023) Eyidoğan, Sadık; Göral, Haydar; Kutlu, Mustafa Kutay
    In this note, we focus on how many arithmetic progressions we have in certain subsets of finite fields. For this purpose, we consider the sets Sp = {t2 : t & ISIN; Fp} and Cp = {t3 : t & ISIN; Fp}, and we use the results on Gauss and Kummer sums. We prove that for any integer k & GE; 3 and for an odd prime number p, the number of k-term arithmetic progressions in Sp is given by p2 2k + R, where and ck is a computable constant depending only on k. The proof also uses finite Fourier analysis and certain types of Weil estimates. Also, we obtain some formulas that give the exact number of arithmetic progressions of length  in the set Sp when  & ISIN; {3,4, 5} and p is an odd prime number. For  = 4, 5, our formulas are based on the number of points on
  • Article
    Citation - WoS: 8
    Citation - Scopus: 7
    Exponential Stability and Boundedness of Nonlinear Perturbed Systems by Unbounded Perturbation Terms
    (Elsevier, 2023) Şahan, Gökhan
    We study the exponential stability and boundedness problem for perturbed nonlinear time-varying systems using Lyapunov Functions with indefinite derivatives. As the limiting function for the perturbation term, we use different forms and give stability and boundedness conditions in terms of the coefficients in these bounds. Contrary to most of the available conditions, we allow the coefficients to be unbounded. But instead, we put forward a condition that requires a series produced by coefficients to be limited and exponentially decaying. We perform our results on Linear time-varying systems and generalize many of the available results. & COPY; 2023 The Franklin Institute. Published by Elsevier Inc. All rights reserved.
  • Article
    Citation - WoS: 1
    Citation - Scopus: 1
    Plaintext Recovery and Tag Guessing Attacks on Authenticated Encryption Algorithm Colm
    (Elsevier, 2022) Ulusoy, Sırrı Erdem; Kara, Orhun; Efe, Mehmet Önder
    There are three main approaches related to cryptanalysis of Authenticated Encryption with Associated Data (AEAD) algorithms: Simulating the encryption oracle (universal forgery attack), simulating the decryption oracle (plaintext recovery attack) and producing the valid tag of a given ciphertext (tag guessing attack). In this work, we analyze the security of COLM in these approaches. COLM is one of the AEAD algorithms chosen in the final portfolio for defense-in-depth use case of the CAESAR competition. The ciphers in this portfolio are supposed to provide robust security with their multiple layered defense mechanisms. The main motivation of this work is to examine if COLM indeed satisfies defense-in-depth security. We make cryptanalysis of COLM, particularly in the chosen ciphertext attack (CCA) scenario, once its secret whitening parameter L=EK(0) is recovered. To the best of our knowledge, we give the first example of querying an EME/EMD (Encrypt-linearMix-Encrypt/Decrypt) AEAD scheme in its decryption direction for arbitrary ciphertexts, not produced previously by the oracle, namely either a forgery or tag guessing attack. We construct SEBC/SDBC (Simulation models of the Encryption/Decryption oracles of the underlying Block Cipher) of COLM, thereby forming the first examples of these models of an authenticated EME scheme simultaneously. The combination of our SEBC/SDBC is a powerful tool to mount a universal forgery attack, a tag guessing attack and a plaintext recovery attack. All of these attacks have polynomial time complexities once L is recovered in the offline phase, indicating that the security of COLM against plaintext recovery and tag guessing attacks is limited by the birthday bound. Apart from exploiting SEBC/SDBC, we mount a pair of plaintext recovery attacks and another universal forgery attack. Finally, we make some suggestions to prevent our attacks.
  • Article
    Citation - WoS: 1
    Citation - Scopus: 1
    Initial Stages of a Three Dimensional Dam Break Flow
    (Elsevier, 2022) Fetahu, Elona; Ivanyshyn Yaman, Olha; Yılmaz, Oğuz
    Short time behavior of a three dimensional, gravity-driven free surface flow is studied analytically and numerically. Initially the fluid is at rest, held by a vertical wall. A rectangular section of the wall suddenly disappears and the gravity driven three-dimensional flow starts. In order to describe the flow in the early stage, the potential theory is employed. Viscous effects are ignored for small times. The leading order problem is solved by using the Fourier series method and an integral equation method. Local analysis of the flow field close to the side edges of the rectangular section reveals a square root singularity. The flow velocity is also log-singular at the bottom edge of the rectangular section. In the limiting case, as the width of the rectangular section approaches infinity, the results of the classical two-dimensional dam break flow are recovered. Three dimensional effects become important closer to the side edges of the rectangular section.
  • Article
    Citation - WoS: 15
    Citation - Scopus: 20
    First Measurement of the Cross Section for Top Quark Pair Production With Additional Charm Jets Using Dileptonic Final States in Pp Collisions at Root S=13 Tev
    (Elsevier, 2021) Karapınar, Güler
    The first measurement of the inclusive cross section for top quark pairs (tt) produced in association with two additional charm jets is presented. The analysis uses the dileptonic final states of tt events produced in proton-proton collisions at a centre-of-mass energy of 13 TeV. The data correspond to an integrated luminosity of 41.5 fb-1, recorded by the CMS experiment at the LHC. A new charm jet identification algorithm provides input to a neural network that is trained to distinguish among tt events with two additional charm (ttcc), bottom (ttbb), and light-flavour or gluon (ttLL) jets. By means of a template fitting procedure, the inclusive ttcc, ttbb, and ttLL cross sections are simultaneously measured, together with their ratios to the inclusive tt + two jets cross section. This provides measurements of the ttcc and ttbb cross sections of 10.1 +/- 1.2 (stat) +/- 1.4 (syst) pb and 4.54 +/- 0.35 (stat) +/- 0.56 (syst) pb, respectively, in the full phase space. The results are compared and found to be consistent with predictions from two different matrix element generators with next-to-leading order accuracy in quantum chromodynamics, interfaced with a parton shower simulation. (c) 2021 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). Funded by SCOAP3.
  • Article
    Citation - WoS: 19
    Citation - Scopus: 24
    Search for W ' Bosons Decaying To a Top and a Bottom Quark at Root S=13 Tev in the Hadronic Final State
    (Elsevier, 2021) Karapınar, Güler
    A search is performed for W ' bosons decaying to a top and a bottom quark in the all-hadronic final state, in proton-proton collisions at a center-of-mass energy of 13TeV. The analyzed data were collected by the CMS experiment between 2016 and 2018 and correspond to an integrated luminosity of 137fb(-1). Deep neural network algorithms are used to identify the jet initiated by the bottom quark and the jet containing the decay products of the top quark when the W ' boson from the top quark decays hadronically. No excess above the estimated standard model background is observed. Upper limits on the production cross sections of W ' bosons decaying to a top and a bottom quark are set. Both left- and right-handed W ' bosons with masses below 3.4TeV are excluded at 95% confidence level, and the most stringent limits to date on W ' bosons decaying to a top and a bottom quark in the all-hadronic final state are obtained. (C) 2021 The Author(s). Published by Elsevier B.V.
  • Conference Object
    Existence and Uniqueness of Solution for Discontinuous Conewise Linear Systems
    (Elsevier, 2020) Şahan, Gökhan
    In this study, we give necessary and sufficient conditions for well posedness of Conewise Linear Systems in 3-dimensional space where the vector field is allowed to be discontinuous. The conditions are stated using the subspaces derived from subsystem matrices and the results are compared with the existing conditions given in the literature. We show that even we don't have a fixed structure on system matrices as in bimodal systems, similar subspaces and numbers again determines well posedness. Copyright (C) 2020 The Authors.
  • Article
    Citation - WoS: 29
    Citation - Scopus: 31
    Studies of Charm and Beauty Hadron Long-Range Correlations in Pp and Ppb Collisions at Lhc Energies
    (Elsevier, 2021) Karapınar, Güler
    Measurements of the second Fourier harmonic coefficient (v(2)) of the azimuthal distributions of prompt and nonprompt D-0 mesons produced in pp and pPb collisions are presented. Nonprompt D-0 mesons come from beauty hadron decays. The data samples are collected by the CMS experiment at nucleon-nucleon center-of-mass energies of 13 and 8.16 TeV, respectively. In high multiplicity pp collisions, v(2) signals for prompt charm hadrons are reported for the first time, and are found to be comparable to those for light-flavor hadron species over a transverse momentum (pT) range of 2-6 GeV. Compared at similar event multiplicities, the prompt D-0 meson v(2) values in pp and pPb collisions are similar in magnitude. The v(2) values for open beauty hadrons are extracted for the first time via nonprompt D-0 mesons in pPb collisions. For pT in the range of 2-5 GeV, the results suggest that v(2) for nonprompt D-0 mesons is smaller than that for prompt D-0 mesons. These new measurements indicate a positive charm hadron v(2) in pp collisions and suggest a mass dependence in v(2) between charm and beauty hadrons in the pPb system. These results provide insights into the origin of heavy-flavor quark collectivity in small systems. (C) 2020 The Author(s). Published by Elsevier B.V.
  • Article
    Citation - WoS: 21
    Citation - Scopus: 33
    Measurement of Prompt D-0 and D-0 Meson Azimuthal Anisotropy and Search for Strong Electric Fields in Pbpb Collisions at Root S-Nn=5.02 Tev
    (Elsevier, 2021) CMS Collaboration; Karapınar, Güler
    The strong Coulomb field created in ultrarelativistic heavy ion collisions is expected to produce a rapiditydependent difference (Av2) in the second Fourier coefficient of the azimuthal distribution (elliptic flow, v2) between D0 (uc) and D0 (uc) mesons. Motivated by the search for evidence of this field, the CMS detector at the LHC is used to perform the first measurement of Av2. The rapidity-averaged value is found to be (Av2) = 0.001 ? 0.001 (stat)? 0.003 (syst) in PbPb collisions at ?sNN = 5.02 TeV. In addition, the influence of the collision geometry is explored by measuring the D0 and D0mesons v2 and triangular flow coefficient (v3) as functions of rapidity, transverse momentum (pT), and event centrality (a measure of the overlap of the two Pb nuclei). A clear centrality dependence of prompt D0 meson v2 values is observed, while the v3 is largely independent of centrality. These trends are consistent with expectations of flow driven by the initial-state geometry. ? 2021 The Author. Published by Elsevier B.V. This is an open access article under the CC BY license