Michal Lukasik

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Mean values and differential distributions of event-shape variables have been studied in neutral current deep inelastic scattering using an integrated luminos-ity of 82.2 pb −1 collected with the ZEUS detector at HERA. The kinematic range is 80 < Q 2 < 20 480 GeV 2 and 0.0024 < x < 0.6, where Q 2 is the virtuality of the exchanged boson and x is the Bjorken(More)
  • S Chekanov, M Derrick, S Magill, B Musgrave, D Nicholass, J Repond +313 others
  • 2008
Bose-Einstein correlations of charged and neutral kaons have been measured in e ± p deep inelastic scattering with an integrated luminosity of 121 pb −1 using the ZEUS detector at HERA. The two-particle correlation function was studied as a function of the four-momentum difference of the kaon pairs, Q 12 = −(p 1 − p 2) 2 , assuming a Gaussian shape for the(More)
Social media is a rich source of rumours and corresponding community reactions. Rumours reflect different characteristics, some shared and some individual. We formulate the problem of classifying tweet level judgements of rumours as a supervised learning task. Both supervised and unsupervised domain adaptation are considered , in which tweets from a rumour(More)
  • S Chekanov, M Derrick, S Magill, B Musgrave, D Nicholass, J Repond +313 others
  • 2008
Beauty production in events containing two muons in the final state has been measured with the ZEUS detector at HERA using an integrated luminosity of 114 pb −1. A low transverse-momentum threshold for muon identification, in combination with the large rapidity coverage of the ZEUS muon system, gives access to almost the full phase space for beauty(More)
Rumours on social media exhibit complex temporal patterns. This paper develops a model of rumour prevalence using a point process, namely a log-Gaussian Cox process , to infer an underlying continuous temporal probabilistic model of post frequencies. To generalize over different rumours , we present a multi-task learning method parametrized by the text in(More)
  • S Chekanov, M Derrick, S Magill, B Musgrave, D Nicholass, J Repond +312 others
  • 2007
Diffractive photoproduction of dijets was measured with the ZEUS detector at the ep collider HERA using an integrated luminosity of 77.2 pb −1. The measurements were made in the kinematic range Q 2 < 1 GeV 2 , 0.20 < y < 0.85 and x IP < 0.025, where Q 2 is the photon virtuality, y is the inelasticity and x IP is the fraction of the proton momentum taken by(More)
Classification of temporal textual data sequences is a common task in various domains such as social media and the Web. In this paper we propose to use Hawkes Processes for classifying sequences of temporal textual data, which exploit both temporal and textual information. Our experiments on rumour stance classification on four Twitter datasets show the(More)
  • S Chekanov, M Derrick, S Magill, B Musgrave, D Nicholass, J Repond +312 others
  • 2008
A search for events with an isolated high-energy lepton and large missing transverse momentum has been performed with the ZEUS detector at HERA using a total integrated luminosity of 504 pb −1. The results agree well with Standard Model predictions. The cross section for production of single W bosons in electron-proton collisions with unpolarised electrons(More)
Exclusive electroproduction of φ mesons has been studied in e ± p collisions at √ s = 318 GeV with the ZEUS detector at HERA using an integrated luminosity of 65.1 pb −1. The γ * p cross section is presented in the kinematic range 2 < Q 2 < 70 GeV 2 , 35 < W < 145 GeV and |t| < 0.6 GeV 2. The cross sections as functions of Q 2 , W , t and helicity angle θ h(More)