Olena Hlushchenko

Measurements of open charm and beauty production cross sections in deep inelastic ep scattering at HERA from the H1 and ZEUS Collaborations are combined. Reduced cross sections are obtained in the kinematic range of negative four-momentum transfer squared of the photon $$2.5~\hbox {GeV}^2\le Q^2 \le 2000\, \hbox {GeV}^2$$ and Bjorken scaling variable $$3 \cdot 10^{-5} \le x_\mathrm{Bj} \le 5 \cdot 10^{-2}$$ . The combination method accounts for the correlations of the statistical and systematic uncertainties among the different datasets. Perturbative QCD calculations are compared to the combined data. A next-to-leading order QCD analysis is performed using these data together with the combined inclusive deep inelastic scattering cross sections from HERA. The running charm- and beauty-quark masses are determined as $$m_c(m_c) = 1.290^{+0.046}_{-0.041} \mathrm{(exp/fit)}$$ $${}^{+0.062}_{-0.014} \mathrm{(model)}$$ $${}^{+0.003}_{-0.031} \mathrm{(parameterisation)}$$ GeV and $$m_b(m_b) = 4.049^{+0.104}_{-0.109} \mathrm{(exp/fit)}$$ $${}^{+0.090}_{-0.032} \mathrm{(model)}$$ $${}^{+0.001}_{-0.031} \mathrm{(parameterisation)}~\mathrm{GeV}$$ .

<abstract> <p>This article highlights the multifaceted role of AI in modern education and offers insights into innovative ways to revolutionize educational practices through AI technologies. Since this article provides comprehension of the scope and depth of AI's impact on the education sphere, it appeals to a diverse readership, encompassing educators, policymakers, researchers, and the general public. This article explores key issues within the domain of AI in education, including personalized learning, AI-driven assessments, data analytics, and the integration of AI into learning management systems. The article highlights promises, potentials, and challenges accompanying this technological advancement. The authors emphasize the need for a balanced and informed approach to using AI to enhance the education system.</p> </abstract>

A simultaneous fit of parton distribution functions (PDFs) and electroweak parameters to HERA data on deep inelastic scattering is presented. The input data are the neutral current and charged current inclusive cross sections which were previously used in the QCD analysis leading to the HERAPDF2.0 PDFs. In addition, the polarization of the electron beam was taken into account for the ZEUS data recorded between 2004 and 2007. Results on the vector and axial-vector couplings of the $Z$ boson to $u$- and $d$-type quarks, on the value of the electroweak mixing angle and the mass of the $W$ boson are presented. The values obtained for the electroweak parameters are in agreement with Standard Model predictions.

The high-precision HERA data allows searches up to TeV scales for beyond the Standard Model contributions to electron–quark scattering. Combined measurements of the inclusive deep inelastic cross sections in neutral and charged current ep scattering corresponding to a luminosity of around 1 fb−1 have been used in this analysis. A new approach to the beyond the Standard Model analysis of the inclusive ep data is presented; simultaneous fits of parton distribution functions together with contributions of “new physics” processes were performed. Results are presented considering a finite radius of quarks within the quark form-factor model. The resulting 95% C.L. upper limit on the effective quark radius is 0.43⋅10−16cm.

High-precision HERA data corresponding to a luminosity of around $1\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ have been used in the framework of $eeqq$ contact interactions (CI) to set limits on possible high-energy contributions beyond the Standard Model to electron-quark scattering. Measurements of the inclusive deep inelastic cross sections in neutral and charged current $ep$ scattering were considered. The analysis of the $ep$ data has been based on simultaneous fits of parton distribution functions including contributions of CI couplings to $ep$ scattering. Several general CI models and scenarios with heavy leptoquarks were considered. Improvements in the description of the inclusive HERA data were obtained for a few models. Since a statistically significant deviation from the Standard Model cannot be established, limits in the TeV range were set on all models considered.

A search for a narrow baryonic state in the $pK^0_S$ and $\bar{p}K^0_S$ system has been performed in $ep$ collisions at HERA with the ZEUS detector using an integrated luminosity of 358 pb$^{-1}$ taken in 2003-2007. The search was performed with deep inelastic scattering events at an $ep$ centre-of-mass energy of 318 GeV for exchanged photon virtuality, $Q^2$, between 20 and 100 $\rm{} GeV^{2}$. Contrary to evidence presented for such a state around 1.52 GeV in a previous ZEUS analysis using a sample of 121 pb$^{-1}$ taken in 1996-2000, no resonance peak was found in the $p(\bar{p})K^0_S$ invariant-mass distribution in the range 1.45-1.7 GeV. Upper limits on the production cross section are set.

The photoproduction of isolated photons has been measured in diffractive events recorded by the ZEUS detector at HERA.Cross sections are evaluated in the photon transverse-energy and pseudorapidity ranges 5 < E γ T < 15 GeV and -0.7 < η γ < 0.9, inclusively, and also with a jet with transverse energy and pseudorapidity in the ranges 4 < E jet T < 35 GeV and -1.5 < η jet < 1.8, using a total integrated electronproton luminosity of 456 pb -1 .A number of kinematic variables were studied and compared to predictions from the RAPGAP Monte Carlo model.An excess of data is observed above the RAPGAP predictions for z meas P > 0.9, where z meas P is the fraction of the longitudinal momentum of the colorless "Pomeron" exchange that is transferred to the photon-jet final state, giving evidence for direct Pomeron interactions.

The high-precision HERA data allows searches up to TeV scales for Beyond the Standard Model contributions to electron-quark scattering. Combined measurements of the inclusive deep inelastic cross sections in neutral and charged current $ep$ scattering corresponding to a luminosity of around 1 fb$^{-1}$ have been used in this analysis. A approach to the beyond the Standard Model analysis of the inclusive $ep$ data is presented; simultaneous fits of parton distribution functions together with contributions of new physics processes were performed. Results are presented considering a finite radius of quarks within the quark form-factor model. The resulting 95% C.L. upper limit on the effective quark radius is $0.43\cdot 10^{-16}$ cm.

A simultaneous fit of parton distribution functions (PDFs) and electroweak parameters to HERA data on deep inelastic scattering is presented. The input data are the neutral current and charged current inclusive cross sections which were previously used in the QCD analysis leading to the HERAPDF2.0 PDFs. In addition, the polarisation of the electron beam was taken into account for the ZEUS data recorded between 2004 and 2007. Results on the vector and axial-vector couplings of the Z boson to u- and d-type quarks, on the value of the electroweak mixing angle and the mass of the W boson are presented. The values obtained for the electroweak parameters are in agreement with Standard Model predictions.

In the work, a study of the operation of the deaeration unit is carried out. An analysis of the operation of two types of deaerators was made: a high-pressure plug-in deaerator with DP-500 columns and a jet-bubble high-pressure deaerator DSP - 500 - M2.

Isolated photons with high transverse energy have been studied in deep inelastic ep scattering with the ZEUS detector at HERA, using an integrated luminosity of 326 pb−1 in the range of exchanged-photon virtuality 10-350 GeV2. Outgoing isolated photons with transverse energy 4 < E < 15 GeV and pseudorapidity − 0.7 < η γ < 0.9 were measured with accompanying jets having transverse energy and pseudorapidity 2.5 < E jet < 35 GeV and −1.5 < ηjet < 1.8, respectively. Differential cross sections are presented for the following variables: the fraction of the incoming photon energy and momentum that is transferred to the outgoing photon and the leading jet; the fraction of the incoming proton energy transferred to the photon and leading jet; the differences in azimuthal angle and pseudorapidity between the outgoing photon and the leading jet and between the outgoing photon and the scattered electron. Comparisons are made with theoretical predictions: a leading-logarithm Monte Carlo simulation, a next-to-leading-order QCD prediction, and a prediction using the k T -factorisation approach.

for the ZEUS Collaboration

Isolated photons with high transverse energy have been studied in deep inelastic $ep$ scattering with the ZEUS detector at HERA, using an integrated luminosity of $326\,$ pb$^{-1}$ in the range of exchanged-photon virtuality $10 - 350$ GeV$^2$. Outgoing isolated photons with transverse energy $4<E_T^\gamma< 15$ GeV and pseudorapidity $-0.7 <\eta^\gamma< 0.9$ were measured with accompanying jets having transverse energy and pseudorapidity $2.5 <E_T^{jet}<35$ GeV and $-1.5<\eta^{jet}< 1.8$, respectively. Differential cross sections are presented for the following variables: the fraction of the incoming photon energy and momentum that is transferred to the outgoing photon and the leading jet; the fraction of the incoming proton energy transferred to the photon and leading jet; the differences in azimuthal angle and pseudorapidity between the outgoing photon and the leading jet and between the outgoing photon and the scattered electron. Comparisons are made with theoretical predictions: a leading-logarithm Monte Carlo simulation, a next-to-leading-order QCD prediction, and a prediction using the $k_T$-factorisation approach.

The work is devoted to the statistical analysis of the text and the study of the dynamics of classification. In the work, the selection of statistical features of the text, the classification of texts belonging to different authors, and the study of the dynamics of classification accuracy depending on the length of text fragments are carried out. To solve the problem, the following methods were used: natural language processing methods; statistical characteristics of texts; machine learning methods; dimensionality reduction methods for visualization capability. On the basis of the obtained dynamics of changes in classification accuracy depending on the lengths of text fragments, appropriate conclusions were drawn regarding the optimal length of texts used for training and testing models. The task was solved in the Jupyter Notebook software environment of the Anaconda distribution, which allows you to immediately install Python and the necessary libraries.

Since the beginning of LHC Run 2, many improvements have been made to the tau lepton reconstruction algorithm at CMS. The hadrons-plus-strips (HPS) tau leptons reconstruction algorithm now benefits from a dynamic strip reconstruction, and has been extended to a version intended for highly Lorentz-boosted topologies. In addition, multivariate discriminators used for tau lepton identification now combine isolation with lifetime variables. The methodology and performance of the newly developed algorithms and discriminators are presented using 35.9 $\textrm{fb}^{-1}$ and 41.4 $\textrm{fb}^{-1}$ of proton-proton data collected with CMS in the 2016 and 2017 LHC runs.

The latest results obtained with CMS data collected at a centre-of-mass energy of 13 TeV targeting Higgs boson decays into tau leptons are shown. The first differential cross section measurement of $H \rightarrow \tau\tau$, as well as the cross-sections measured for individual ZH and WH production mechanisms, are presented. The updated limits on anomalous vector boson couplings show no significant deviations from the standard model predictions.

The latest results obtained with CMS data collected at a centre-of-mass energy of 13 TeV targeting Higgs boson decays into leptonic final states at CMS are discussed. The first differential cross section measurement of $H \rightarrow \tau\tau$, as well as the cross-sections measured for individual ZH and WH production mechanisms, is presented. The updated limits on anomalous vector boson couplings show no significant deviations from the standard model predictions.