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Creators/Authors contains: "Khalil, S."

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  1. This work is concerned with the introduction and development of a technique to optimally position a Mobile Sensor (MS) in a location with adequate side lobe Radio Frequency (RF) signal power. The proposed method involves the generation of a database (DB) of side lobe power distribution for different azimuth angles of the downlink transmitted signal. The generated DB is subsequently used to train and test a Machine Learning (ML) multiclass classifier, as well as two distinct Convolution Neural Networks (CNN), to identify the desired MS location. Simulation experiments are performed which indicate a maximum accuracy of 99.25%, 96.56% and 96.10% for 8 different receiver locations. 
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  2. Free, publicly-accessible full text available January 1, 2026
  3. The first observation of the concurrent production of two J / ψ mesons in proton-nucleus collisions is presented. The analysis is based on a proton-lead ( p Pb ) data sample recorded at a nucleon-nucleon center-of-mass energy of 8.16 TeV by the CMS experiment at the CERN LHC and corresponding to an integrated luminosity of 174.6 nb 1 . The two J / ψ mesons are reconstructed in their μ + μ decay channels with transverse momenta p T > 6.5 GeV and rapidity | y | < 2.4 . Events where one of the J / ψ mesons is reconstructed in the dielectron channel are also considered in the search. The p Pb J / ψ J / ψ + X process is observed with a significance of 5.3 standard deviations. The measured inclusive fiducial cross section, using the four-muon channel alone, is σ ( p Pb J / ψ J / ψ + X ) = 22.0 ± 8.9 ( stat ) ± 1.5 ( syst ) nb . A fit of the data to the expected rapidity separation for pairs of J / ψ mesons produced in single (SPS) and double (DPS) parton scatterings yields σ SPS p Pb J / ψ J / ψ + X = 16.5 ± 10.8 ( stat ) ± 0.1 ( syst ) nb and σ DPS p Pb J / ψ J / ψ + X = 5.4 ± 6.2 ( stat ) ± 0.4 ( syst ) nb , respectively. This latter result can be transformed into a lower bound on the effective DPS cross section, closely related to the squared average interparton transverse separation in the collision, of σ eff > 1.0 mb at 95% confidence level. © 2024 CERN, for the CMS Collaboration2024CERN 
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    Free, publicly-accessible full text available November 1, 2025
  4. A<sc>bstract</sc> A search for the central exclusive production of top quark-antiquark pairs ($$ \textrm{t}\overline{\textrm{t}} $$ t t ¯ ) is performed for the first time using proton-tagged events in proton-proton collisions at the LHC at a centre-of-mass energy of 13 TeV. The data correspond to an integrated luminosity of 29.4 fb−1. The$$ \textrm{t}\overline{\textrm{t}} $$ t t ¯ decay products are reconstructed using the central CMS detector, while forward protons are measured in the CMS-TOTEM precision proton spectrometer. An observed (expected) upper bound on the production cross section of 0.59 (1.14) pb is set at 95% confidence level, for collisions of protons with fractional momentum losses between 2 and 20%. 
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    Free, publicly-accessible full text available June 1, 2025