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Öğe EULER–ZAGIER SUMS VIA TRIGONOMETRIC SERIES(Publishing House of the Romanian Academy, 2023) Çelik, Şermin Çam; Göral, HaydarIn this note, we study the evaluations of Euler sums via trigonometric series. It is a commonly believed conjecture that for an even weight greater than seven, Euler sums cannot be evaluated in terms of the special values of the Riemann zeta function. For an even weight, we reduce the evaluations of Euler sums into the evaluations of double series and integrals of products of Clausen functions. We also re-evaluate Euler sums of odd weight using a new method based on trigonometric series. © 2023 Editura Academiei Romane. All rights reserved.Öğe Optimizing percutaneous pulmonary valve implantation with patient-specific 3D-printed pulmonary artery models and hemodynamic assessment(Frontiers Media SA, 2023) Ödemiş, Ender; Aka, İbrahim Başar; Ali, Mhd Homam Aljah; Gümüş, Terman; Pekkan, KeremAbstract Background: Percutaneous pulmonary valve implantation (PPVI) has emerged as a less invasive alternative for treating severe pulmonary regurgitation after tetralogy of Fallot (TOF) repair in patients with a native right ventricular outflow tract (RVOT). However, the success of PPVI depends on precise patient-specific valve sizing, the avoidance of oversizing complications, and optimal valve performance. In recent years, innovative adaptations of commercially available cardiovascular mock loops have been used to test conduits in the pulmonary position. These models are instrumental in facilitating accurate pulmonic valve sizing, mitigating the risk of oversizing, and providing insight into the valve performance before implantation. This study explored the utilization of custom-modified mock loops to implant patient-specific 3D-printed pulmonary artery geometries, thereby advancing PPVI planning and execution. Material and Methods: Patient-specific 3D-printed pulmonary artery geometries of five patients who underwent PPVI using Pulsta transcatheter heart valve (THV) ® were tested in a modified ViVitro pulse duplicator system®. Various valve sizes were subjected to 10 cycles of testing at different cardiac output levels. The transpulmonary systolic and regurgitation fractions of the valves were also recorded and compared. Results: A total of 39 experiments were conducted using five different patient geometries and several different valve sizes (26, 28, 30, and 32 mm) at 3, 4, and 5 L/min cardiac output at heart rates of 70 beats per minute (bpm) and 60/40 systolic/diastolic ratios. The pressure gradients and regurgitation fractions of the tested valve sizes in the models were found to be similar to the pressure gradients and regurgitation fractions of valves used in real procedures. However, in two patients, different valve sizes showed better hemodynamic values than the actual implanted valves. Discussion: The use of 3D printing technology, electromagnetic flow meters, and the custom-modified ViVitro pulse duplicator system® in conjunction with patient-specific pulmonary artery models has enabled a comprehensive assessment of percutaneous pulmonic valve implantation performance. This approach allows for accurate valve sizing, minimization of oversizing risks, and valuable insights into hemodynamic behavior before implantation. The data obtained from this experimental setup will contribute to advancing PPVI procedures and offer potential benefits in improving patient outcomes and safety. 2024 Odemis, AKA, Ali, Gumus and Pekkan.Öğe Publisher Correction: Observation of triple J/ψ meson production in proton-proton collisions(Nature Research, 2023) Yetkin, Elif AslıAbstract Correction to: Nature Physics, published online 19 January 2023. In the version of the article initially published, the second affiliation of T. Elkafrawy was incorrect and is now shown as Ain Shams University, Cairo, Egypt in the HTML and PDF versions of the article. © 2023, CERN.Öğe Publisher Correction: Observation of triple J/ψ meson production in proton-proton collisions (Nature Physics, (2023), 19, 3, (338-350), 10.1038/s41567-022-01838-y)(Nature Research, 2023-03) Yetkin, Elif AslıCorrection to: Nature Physics. Published online 19 January 2023. In the version of this article initially published, the first affiliation—Yerevan Physics Institute, Yerevan, Armenia—was missing from the list of author affiliations and has now been inserted in the HTML and PDF versions of the article. © 2023, The Author(s).Öğe Differential tt¯ cross-section measurements using boosted top quarks in the all-hadronic final state with 139 fb −1 of ATLAS data(Springer Science and Business Media Deutschland GmbH, 2023-04) Çetin, Serkant AliMeasurements of single-, double-, and triple-differential cross-sections are presented for boosted top-quark pair-production in 13 TeV proton–proton collisions recorded by the ATLAS detector at the LHC. The top quarks are observed through their hadronic decay and reconstructed as large-radius jets with the leading jet having transverse momentum (pT) greater than 500 GeV. The observed data are unfolded to remove detector effects. The particle-level cross-section, multiplied by the tt¯ → WWbb¯ branching fraction and measured in a fiducial phase space defined by requiring the leading and second-leading jets to have pT> 500 GeV and pT> 350 GeV, respectively, is 331 ± 3(stat.) ± 39(syst.) fb. This is approximately 20% lower than the prediction of 398−49+48 fb by Powheg+Pythia 8 with next-to-leading-order (NLO) accuracy but consistent within the theoretical uncertainties. Results are also presented at the parton level, where the effects of top-quark decay, parton showering, and hadronization are removed such that they can be compared with fixed-order next-to-next-to-leading-order (NNLO) calculations. The parton-level cross-section, measured in a fiducial phase space similar to that at particle level, is 1.94 ± 0.02(stat.) ± 0.25(syst.) pb. This agrees with the NNLO prediction of 1.96−0.17+0.02 pb. Reasonable agreement with the differential cross-sections is found for most NLO models, while the NNLO calculations are generally in better agreement with the data. The differential cross-sections are interpreted using a Standard Model effective field-theory formalism and limits are set on Wilson coefficients of several four-fermion operators. [Figure not available: see fulltext.]. © 2023, The Author(s).Öğe Measurements of the suppression and correlations of dijets in Pb+Pb collisions at√sNN = 5.02 TeV(American Physical Society, 2023-05) Çetin, Serkant AliStudies of the correlations of the two highest transverse momentum (leading) jets in individual Pb+Pb collision events can provide information about the mechanism of jet quenching by the hot and dense matter created in such collisions. In Pb+Pb and pp collisions at√sNN = 5.02 TeV, measurements of the leading dijet transverse momentum (pT) correlations are presented. Additionally, measurements in Pb+Pb collisions of the dijet pair nuclear modification factors projected along leading and subleading jet pT are made. The measurements are performed using the ATLAS detector at the LHC with 260 pb−1 of pp data collected in 2017 and 2.2 nb−1 of Pb+Pb data collected in 2015 and 2018. An unfolding procedure is applied to the two-dimensional leading and subleading jet pT distributions to account for experimental effects in the measurement of both jets. Results are provided for dijets with leading jet pT greater than 100 GeV. Measurements of the dijet-yield-normalized xJ distributions in Pb+Pb collisions show an increased fraction of imbalanced jets compared to pp collisions; these measurements are in agreement with previous measurements of the same quantity at 2.76 TeV in the overlapping kinematic range. Measurements of the absolutely normalized dijet rate in Pb+Pb and pp collisions are also presented, and show that balanced dijets are significantly more suppressed than imbalanced dijets in Pb+Pb collisions. It is observed in the measurements of the pair nuclear modification factors that the subleading jets are significantly suppressed relative to leading jets with pT between 100 and 316 GeV for all centralities in Pb+Pb collisions. ©2023 CERN, for the ATLAS Collaboration.Öğe Measurement of muon pairs produced via γγ scattering in nonultraperipheral Pb + Pb collisions at √sNN = 5.02 TeV with the ATLAS detector(American Physical Society, 2023-05) Çetin, Serkant AliResults of a measurement of dimuon photoproduction in nonultraperipheral Pb + Pb collisions at √sNN = 5.02 TeV are presented. Themeasurement uses ATLAS data from the 2015 and 2018 Pb + Pb data-taking periods at the LHC with an integrated luminosity of 1.94 nb.1. The γγ → μ+ μ- pairs are identified via selections on pair momentum asymmetry and acoplanarity. Differential cross sections for dimuon production are measured in different centrality, average muon momentum, and pair rapidity intervals as functions of acoplanarity and k⊥, the transverse momentum kick of one muon relative to the other. Measurements are also made as a function of the rapidity separation of the muons and the angle of the muon pair relative to the second-order event plane to test whether magnetic fields generated in the quark-gluon plasma affect the measured muons. A prior observation of a centrality-dependent broadening of the acoplanarity distribution is confirmed. Furthermore, the improved precision of the measurement reveals a depletion in the number of pairs having small acoplanarity or k⊥ values in more central collisions. The acoplanarity distributions in a given centrality interval are observed to vary with the mean pT of the muons in the pair, but the k⊥ distributions do not. Comparisons with recent theoretical predictions are made. The predicted trends associated with effects of magnetic fields on the dimuons are not observed. © 2023 CERN, for the ATLAS Collaboration.Öğe Search for CP violation using (Formula presented.) events in the lepton+jets channel in pp collisions at ?s = 13 TeV(Springer Science and Business Media Deutschland GmbH, 2023-06) Yetkin, Elif AslıResults are presented on a search for CP violation in the production and decay of top quark-antiquark pairs in the lepton+jets channel. The search is based on data from proton-proton collisions at s = 13 TeV, collected with the CMS detector, corresponding to an integrated luminosity of 138 fb?1. Possible CP violation effects are evaluated by measuring asymmetries in observables constructed from linearly independent four-momentum vectors of the final-state particles. The dimensionless chromoelectric dipole moment of the top quark obtained from the observed asymmetries is measured to be 0.04 ± 0.10 (stat) ± 0.07(syst), and the asymmetries exhibit no evidence for CP-violating effects, consistent with expectations from the standard model. [Figure not available: see fulltext.]. © 2023, The Author(s).Öğe Search for heavy resonances and quantum black holes in e?, e?, and ?? final states in proton-proton collisions at ?s = 13 TeV(Springer Science and Business Media Deutschland GmbH, 2023-06) Yetkin, Elif AslıA search is reported for heavy resonances and quantum black holes decaying into e?, e?, and ?? final states in proton-proton collision data recorded by the CMS experiment at the CERN LHC during 2016–2018 at s = 13 TeV, corresponding to an integrated luminosity of 138 fb?1. The e?, e?, and ?? invariant mass spectra are reconstructed, and no evidence is found for physics beyond the standard model. Upper limits are set at 95% confidence level on the product of the cross section and branching fraction for lepton flavor violating signals. Three benchmark signals are studied: resonant ? sneutrino production in R parity violating supersymmetric models, heavy Z? gauge bosons with lepton flavor violating decays, and nonresonant quantum black hole production in models with extra spatial dimensions. Resonant ? sneutrinos are excluded for masses up to 4.2TeV in the e? channel, 3.7TeV in the e? channel, and 3.6TeV in the ?? channel. A Z? boson with lepton flavor violating couplings is excluded up to a mass of 5.0TeV in the e? channel, up to 4.3Te V in the e? channel, and up to 4.1TeV in the ?? channel. Quantum black holes in the benchmark model are excluded up to the threshold mass of 5.6TeV in the e? channel, 5.2TeV in the e? channel, and 5.0TeV in the ?? channel. In addition, model-independent limits are extracted to allow comparisons with other models for the same final states and similar event selection requirements. The results of these searches provide the most stringent limits available from collider experiments for heavy particles that undergo lepton flavor violating decays. [Figure not available: see fulltext.]. © 2023, The Author(s).Öğe Search for Higgs boson decays to a Z boson and a photon in proton-proton collisions at ?s = 13 TeV(Springer Science and Business Media Deutschland GmbH, 2023-06) Yetkin, Elif AslıResults are presented from a search for the Higgs boson decay H ? Z?, where Z ? ?+?? with ? = e or ?. The search is performed using a sample of proton-proton (pp) collision data at a center-of-mass energy of 13 TeV, recorded by the CMS experiment at the LHC, corresponding to an integrated luminosity of 138 fb?1. Events are assigned to mutually exclusive categories, which exploit differences in both event topology and kinematics of distinct Higgs production mechanisms to enhance signal sensitivity. The signal strength ?, defined as the product of the cross section and the branching fraction ?pp?HBH?Z? relative to the standard model prediction, is extracted from a simultaneous fit to the ?+??? invariant mass distributions in all categories and is measured to be ? = 2.4 ± 0.9 for a Higgs boson mass of 125.38 GeV. The statistical significance of the observed excess of events is 2.7 standard deviations. This measurement corresponds to ?pp?HBH?Z?=0.21±0.08 pb. The observed (expected) upper limit at 95% confidence level on ? is 4.1 (1.8), where the expected limit is calculated under the background-only hypothesis. The ratio of branching fractions BH?Z?/BH??? is measured to be 1.5?0.6+0.7, which agrees with the standard model prediction of 0.69 ± 0.04 at the 1.5 standard deviation level. © The Author(s) 2023.Öğe Hermogenes in asia minor: Giving spatial presence to temples of dionysus and artemis leukophryene in virtual space(International Society for Photogrammetry and Remote Sensing, 2023-06-24) Denker, AhmetHermogenes and his works in Asia Minor is one of the central subjects of research in both classical architecture and archaeology. In this study, the questions of what role Hermogenes played in Hellenistic architecture, what he intended and built, and why Vitruvius gave him the highest praise are once again brought up. The Temple of Dionysus in Teos and the Temple of Artemis Leukophryene in Magnesia are masterpieces of the great architect Hermogenes, who left his mark on temple architecture in Asia Minor during the Hellenistic period. Both of these temples are now in ruins. The pedestals of several columns, the lower shafts of the columns and a few fallen Ionic capitals convey the buildings' former beauty, but few vestiges remain of these important sanctuaries. Yet these marble monuments still captivate the imagination, twenty-Two centuries after they were built. As a result of a systematic and comprehensive application of digital 3D reconstruction methodology, 3D visualizations of these works of this famous architect of the Hellenistic period are created and presented. © 2023 International Society for Photogrammetry and Remote Sensing. All rights reserved.Öğe Search for direct pair production of supersymmetric partners of ? leptons in the final state with two hadronically decaying ? leptons and missing transverse momentum in proton-proton collisions at Formula Presented(American Physical Society, 2023-07-01) Yetkin, Elif AslıA search for the direct production of a pair of ? sleptons, the supersymmetric partners of ? leptons, is presented. Each ? slepton is assumed to decay to a ? lepton and the lightest supersymmetric particle (LSP), which is assumed to be stable and to not interact in the detector, leading to an imbalance in the total reconstructed transverse momentum. The search is carried out in events identified as containing two ? leptons, each decaying to one or more hadrons and a neutrino, and significant transverse momentum imbalance. In addition to scenarios in which the ? sleptons decay promptly, the search also addresses scenarios in which the ? sleptons have sufficiently long lifetimes to give rise to nonprompt ? leptons. The data were collected in proton-proton collisions at a center-of-mass energy of 13 TeV at the CERN LHC with the CMS detector in 2016-2018, and correspond to an integrated luminosity of 138 fb - 1 . No significant excess is seen with respect to standard model expectations. Upper limits on cross sections for the pair production of ? sleptons are obtained in the framework of simplified models. In a scenario in which the ? sleptons are superpartners of left-handed ? leptons, and each undergoes a prompt decay to a ? lepton and a nearly massless LSP, ? slepton masses between 115 and 340 GeV are excluded. In a scenario in which the lifetime of the ? sleptons corresponds to c ? 0 = 0.1 mm , where ? 0 represents the mean proper lifetime of the ? slepton, masses between 150 and 220 GeV are excluded. © 2023 CERN, for the CMS Collaboration.Öğe Search for narrow resonances in the Formula Presented-tagged dijet mass spectrum in proton-proton collisions at Formula Presented(American Physical Society, 2023-07-01) Yetkin, Elif AslıA search is performed for narrow resonances decaying to final states of two jets, with at least one jet originating from a b quark, in proton-proton collisions at s = 13 TeV . The data set corresponds to an integrated luminosity of 138 fb - 1 collected with the CMS detector at the LHC. Jets originating from energetic b hadrons are identified through a b -tagging algorithm that utilizes a deep neural network or the presence of a muon inside a jet. The invariant mass spectrum of jet pairs is well described by a smooth parametrization and no evidence for the production of new particles is observed. Upper limits on the production cross section are set for excited b quarks and other resonances decaying to dijet final states containing b quarks. These limits exclude at 95% confidence level models of Z ? bosons with masses from 1.8 TeV to 2.4 TeV and of excited b quarks with masses from 1.8 TeV to 4.0 TeV. This is the most stringent exclusion of excited b quarks to date. © 2023 CERN, for the CMS Collaboration.Öğe Search for the exotic decay of the Higgs boson into two light pseudoscalars with four photons in the final state in proton-proton collisions at s = 13 TeV(Springer Science and Business Media Deutschland GmbH, 2023-07) Yetkin, Elif AslıA search for the exotic decay of the Higgs boson to a pair of light pseudoscalars, each of which subsequently decays into a pair of photons, is presented. The search uses data from proton-proton collisions at s = 13 TeV recorded with the CMS detector at the LHC that corresponds to an integrated luminosity of 132 fb?1. The analysis probes pseudoscalar bosons with masses in the range 15–62 GeV, coming from the Higgs boson decay, which leads to four well-isolated photons in the final state. No significant deviation from the background-only hypothesis is observed. Upper limits are set on the product of the Higgs boson production cross section and branching fraction into four photons. The observed (expected) limits range from 0.80 (1.00) fb for a pseudoscalar boson mass of 15 GeV to 0.26 (0.24) fb for a mass of 62 GeV at 95% confidence level. © The Author(s) 2023.Öğe Constraints on anomalous Higgs boson couplings to vector bosons and fermions from the production of Higgs bosons using the ?? final state(American Physical Society, 2023-08-01) Yetkin, Elif AslıA study of anomalous couplings of the Higgs boson to vector bosons and fermions is presented. The data were recorded by the CMS experiment at a center-of-mass energy of pp collisions at the LHC of 13 TeV and correspond to an integrated luminosity of 138 fb - 1 . The study uses Higgs boson candidates produced mainly in gluon fusion or electroweak vector boson fusion at the LHC that subsequently decay to a pair of ? leptons. Matrix-element and machine-learning techniques were employed in a search for anomalous interactions. The results are combined with those from the four-lepton and two-photon decay channels to yield the most stringent constraints on anomalous Higgs boson couplings to date. The pure C P -odd scenario of the Higgs boson coupling to gluons is excluded at 2.4 standard deviations. The results are consistent with the standard model predictions. © 2023 CERN, for the CMS Collaboration.Öğe Observation of gauge boson joint-polarisation states in W±Z production from pp collisions at s=13 TeV with the ATLAS detector(Elsevier B.V., 2023-08) Çetin, Serkant AliMeasurements of joint-polarisation states of W and Z gauge bosons in W±Z production are presented. The data set used corresponds to an integrated luminosity of 139 fb?1 of proton–proton collisions at a centre-of-mass energy of 13 TeV recorded by the ATLAS detector at the CERN Large Hadron Collider. The W±Z candidate events are reconstructed using leptonic decay modes of the gauge bosons into electrons and muons. The simultaneous pair-production of longitudinally polarised vector bosons is measured for the first time with a significance of 7.1 standard deviations. The measured joint helicity fractions integrated over the fiducial region are f00=0.067±0.010, f0T=0.110±0.029, fT0=0.179±0.023 and fTT=0.644±0.032, in agreement with the next-to-leading-order Standard Model predictions. Individual helicity fractions of the W and Z bosons are also measured and found to be consistent with joint helicity fractions within the expected amounts of correlation. Both the joint and individual helicity fractions are also measured separately in W+Z and W?Z events. Inclusive and differential cross sections for several kinematic observables sensitive to polarisation are presented. © 2023Öğe Measurement of the Higgs boson mass in the H???ZZ????4? decay channel using 139 fb?1 of s=13 TeV pp collisions recorded by the ATLAS detector at the LHC(ELSEVIER, 2023-08-10) Çetin, Serkant AliThe mass of the Higgs boson is measured in the H?ZZ??4? decay channel. The analysis uses proton–proton collision data from the Large Hadron Collider at a centre-of-mass energy of 13 TeV recorded by the ATLAS detector between 2015 and 2018, corresponding to an integrated luminosity of 139 fb?1. The measured value of the Higgs boson mass is 124.99±0.18(stat.)±0.04(syst.) GeV. In final states with muons, this measurement benefits from an improved momentum-scale calibration relative to that adopted in previous publications. The measurement also employs an analytic model that takes into account the invariant-mass resolution of the four-lepton system on a per-event basis and the output of a deep neural network discriminating signal from background events. This measurement is combined with the corresponding measurement using 7 and 8 TeV pp collision data, resulting in a Higgs boson mass of 124.94±0.17(stat.)±0.03(syst.) GeV. © 2023 The Author(s)Öğe Measurement of the charge asymmetry in top-quark pair production in association with a photon with the ATLAS experiment(Elsevier B.V., 2023-08-10) Çetin, Serkant AliA measurement of the charge asymmetry in top-quark pair (tt¯) production in association with a photon is presented. The measurement is performed in the single-lepton tt¯ decay channel using proton–proton collision data collected with the ATLAS detector at the Large Hadron Collider at CERN at a centre-of-mass-energy of 13 TeV during the years 2015–2018, corresponding to an integrated luminosity of 139 fb?1. The charge asymmetry is obtained from the distribution of the difference of the absolute rapidities of the top quark and antiquark using a profile likelihood unfolding approach. It is measured to be AC=?0.003±0.029 in agreement with the Standard Model expectation. © 2023 The Author(s)Öğe Observation of an Excess of Dicharmonium Events in the Four-Muon Final State with the ATLAS Detector(American Physical Society, 2023-10-11) Çetin, Serkant AliA search is made for potential ccc? c? tetraquarks decaying into a pair of charmonium states in the four ffiffi muon final state using proton-proton collision data at ps ¼ 13 TeV, corresponding to an integrated luminosity of 140 fb?1 recorded by the ATLAS experiment at LHC. Two decay channels, J=? ? J=? ? 4? and J=? ? ? ?2S? ? 4?, are studied. Backgrounds are estimated based on a hybrid approach involving Monte Carlo simulations and data-driven methods. Statistically significant excesses with respect to backgrounds dominated by the single parton scattering are seen in the di-J=? channel consistent with a narrow resonance at 6.9 GeV and a broader structure at lower mass. A statistically significant excess is also seen in the J=? ? ? ?2S? channel. The fitted masses and decay widths of the structures are reported. © 2023 CERN, for the ATLAS Collaboration.Öğe Erratum: Search for exclusive Higgs and Z boson decays to ?? and ?? with the ATLAS detector(SPRINGER, 2023-12-22) Çakır, AffanOne correction is noted for the paper. The calculation of an angle used to account for meson polarisation in the signal decays was not correct.
