Publications by authors named "Malfattore G"

Article Synopsis
  • The Letter reports the most accurate measurement so far of the matter-antimatter imbalance during Pb-Pb collisions at a high energy level of 5.02 TeV.
  • It utilizes the Statistical Hadronization framework to determine precise values for the electric charge and baryon chemical potentials, μ_{Q} and μ_{B}.
  • The analysis of antiparticle-to-particle yield ratios shows that the collisions create a system that is generally baryon-free and electrically neutral at midrapidity.
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The ALICE Collaboration reports the measurement of semi-inclusive distributions of charged-particle jets recoiling from a high transverse momentum (high p_{T}) hadron trigger in proton-proton and central Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV. A data-driven statistical method is used to mitigate the large uncorrelated background in central Pb-Pb collisions.

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K^{+}K^{-} pairs may be produced in photonuclear collisions, either from the decays of photoproduced ϕ(1020) mesons or directly as nonresonant K^{+}K^{-} pairs. Measurements of K^{+}K^{-} photoproduction probe the couplings between the ϕ(1020) and charged kaons with photons and nuclear targets. The kaon-proton scattering occurs at energies far above those available elsewhere.

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Article Synopsis
  • - This Letter discusses the measurement of ridge yields from charged hadron angular correlations in proton-proton collisions at a high energy of 13 TeV, specifically within certain pseudorapidity and transverse momentum ranges.
  • - The research extends ridge yield measurements to low charged-particle multiplicity regions, where typically a strong interacting medium is not expected to form during collisions.
  • - Findings indicate that ridge yields in pp collisions are significantly higher than those observed in e^{+}e^{-} collisions, suggesting that processes in e^{+}e^{-} annihilations do not significantly influence long-range correlations in proton-proton interactions.
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Article Synopsis
  • The ALICE detector measured the cross section for incoherent photonuclear production of J/ψ vector mesons, focusing on the Mandelstam |t| variable, during ultraperipheral collisions of Pb nuclei at a very high energy of 5.02 TeV.
  • The measurement was conducted within a rapidity interval of |y|<0.8 and covers a specific range of Bjorken-x values.
  • Analysis showed that models without quantum fluctuations in the gluon density predicted a much steeper |t|-dependence than observed, but including these fluctuations improved the models' alignment with the data.
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The production of the ψ(2S) charmonium state was measured with ALICE in Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV, in the dimuon decay channel. A significant signal was observed for the first time at LHC energies down to zero transverse momentum, at forward rapidity (2.

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Article Synopsis
  • Understanding how parton mass and Casimir color factors affect heavy quark emissions is key to studying quantum chromodynamics (QCD).
  • This research presents the first experimental constraint on the charm-quark splitting function, obtained through measurements in proton-proton collisions at 13 TeV.
  • Findings indicate that charm quarks show a steeper splitting function compared to gluons and light quarks, experiencing fewer emissions with a lower likelihood of large-angle emissions.
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The most precise measurements to date of the _{Λ}^{3}H lifetime τ and Λ separation energy B_{Λ} are obtained using the data sample of Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV collected by ALICE at the LHC. The _{Λ}^{3}H is reconstructed via its charged two-body mesonic decay channel (_{Λ}^{3}H→^{3}He+π^{-} and the charge-conjugate process).

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The transverse-momentum (p_{T}) spectra and coalescence parameters B_{2} of (anti)deuterons are measured in p-p collisions at sqrt[s]=13  TeV for the first time in and out of jets. In this measurement, the direction of the leading particle with the highest p_{T} in the event (p_{T}^{lead}>5  GeV/c) is used as an approximation for the jet axis. The event is consequently divided into three azimuthal regions, and the jet signal is obtained as the difference between the toward region, that contains jet fragmentation products in addition to the underlying event (UE), and the transverse region, which is dominated by the UE.

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