arXiv subjects

Antoni Marcinek

Publications and source records attributed to Antoni Marcinek.

5 recordsLinked to original sources

arXiv2025

New results on $\phi$(1020) production from the NA61/SHINE experiment at CERN SPS

NA61/SHINE is a multipurpose, fixed-target hadron spectrometer at the CERN SPS. Its research program includes studies of strong interactions as well as reference measurements for neutrino and cosmic-ray physics. A significant advantage of NA61/SHINE over collider experiments is its extended coverage of phase space available for particle production. This includes the entire projectile hemisphere of the collision, with no low-pT cut-off. The energy and system-size dependence of strangeness production plays an essential role in studies of the transition from confined to deconfined matter. With its zero net strangeness and its valence structure composed predominantly of s and $\bar{s}$ valence quarks, the $\phi$(1020) meson will not be sensitive to strangeness-related effects in a purely hadronic scenario, but will behave like a doubly strange particle in a partonic system. This contribution presents the first-ever results on $\phi$(1020) meson production in intermediate-size systems at the CERN SPS, that is, central Ar+Sc collisions at $\sqrt{s_\text{NN}}$ = 8.8, 11.9, and 16.8 GeV. The presented results include double-differential rapidity-transverse momentum (y-pT) distributions, transverse mass (mT) spectra at midrapidity, pT-integrated rapidity spectra, mean multiplicities (4$\pi$ yields), and particle ratios. These are compared to data on Pb+Pb and p+p collisions. A discussion of open and hidden strangeness production enhancement is included. Finally, a comparison with three microscopic models is shown, demonstrating their overall failure in describing these new measurements.

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arXiv2025

News from the strong interaction program of NA61/SHINE

The NA61/SHINE experiment at the CERN SPS is a multipurpose fixed-target spectrometer for charged and neutral hadron measurements. Its research program includes studies of strong interactions as well as reference measurements for neutrino and cosmic-ray physics. This contribution summarizes a selected set of new results from our strong interaction program, including system-size and energy dependence of charged kaon to pion production, $\phi$(1020) spectra in Ar+Sc collisions and enhancement over p+p reactions, femtoscopy of like-sign pions 0 in Ar+Sc and Be+Be collisions, $D^0+\overline{D}^0$ (open charm) yield in Xe+La interactions, and finally an unexpected excess of charged over neutral kaon production indicating a strong violation of isospin symmetry in Ar+Sc collisions.

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arXiv2022

Highlights from the NA61/SHINE experiment

The NA61/SHINE experiment is a fixed-target, broad acceptance facility at the CERN SPS. This contribution summarizes the most recent results from the strong interactions NA61/SHINE programme and presents news on the detector upgrade in preparation for the future data taking. The strong interactions programme consists in a two-dimensional scan in beam momentum (from 13A to 150A/158A GeV/c, \sqrt{s_{NN}} from 5.1 to 17.3 GeV) and system size (p + p, Be + Be, Ar + Sc, Xe + La reactions). The experiment searches for the second-order critical end-point in the temperature versus baryo-chemical potential phase diagram and studies the properties of the onset of deconfinement discovered by its predecessor, NA49 at the CERN SPS. The presented results include K/π multiplicity ratios as a function of energy and system size, singly and multi-strange hadron production in p + p reactions, multiplicity and net-charge fluctuations measured by higher order moments in p + p, Be + Be and Ar + Sc collisions, proton and charged hadron intermittency in Ar + Sc and Pb + Pb reactions, HBT measurements in Ar + Sc and collective electromagnetic effects in Ar + Sc collisions.

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arXiv2019

Can pion spectra in Pb+Pb collisions at CERN SPS energies be described by those in p+p reactions and energy-momentum conservation ? Rapidity distributions of pions in p+p and Pb+Pb collisions at CERN SPS energies

The centrality dependence of rapidity distributions of pions in Pb+Pb reactions can be understood by imposing local energy-momentum conservation in the longitudinal "fire-streaks" of excited matter. With no tuning nor adjustment to the experimental data, the rapidity distribution of pions produced by the fire-streak which we obtained from Pb+Pb collisions reproduces the shape of the experimental pion rapidity distribution in p+p interactions, measured by the NA49 Collaboration at the same energy. The observed difference in the absolute normalization of this distribution can be explained by the difference in the overall energy balance, induced by baryon stopping and strangeness enhancement phenomena occurring in heavy ion collisions. We estimate the latter effects using a collection of SPS experimental data on $π^\pm$, $K^\pm$, net $p$, and $n$ production in p+p and Pb+Pb reactions. Implications of the above findings are discussed.

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arXiv2017

New baryonic and mesonic observables from NA61/SHINE

One of the main objectives of the NA61/SHINE experiment at the CERN SPS is to study properties of strongly interacting matter. This paper presents new results on observables relevant for this part of the NA61/SHINE programme. These include the first ever measurements of $ϕ$ meson production in p+p collisions at 40 and 80 GeV, and most detailed ever experimental data at 158 GeV. This contribution demonstrates the superior accuracy of the present dataset with respect to existing measurements. The comparison of p+p to Pb+Pb collisions shows a non-trivial system size dependence of the longitudinal evolution of hidden strangeness production, contrasting with that of other mesons. Furthermore, proton density fluctuations are investigated as a possible order parameter of the second order phase transition in the neighbourhood of the critical point (CP) of strongly interacting matter. An intermittency analysis is performed of the proton second scaled factorial moments in transverse momentum space. A previous analysis of this sort revealed significant power-law fluctuations for the "Si"+Si system at 158A GeV measured by the NA49 experiment. The fitted power-law exponent was consistent within errors with the theoretically expected critical value, a result suggesting a baryochemical potential in the vicinity of the CP of about 250 MeV. The analysis will now be extended to NA61/SHINE systems of similar size, Be+Be and Ar+Sc, at 150A GeV. Finally, spectator-induced electromagnetic (EM) effects on charged meson production are being studied and bring information on the space-time position of the pion formation zone, which appears to be much closer to the spectator system for faster pions than for slower ones. On that basis, we demonstrate that the longitudinal evolution of the system at CERN SPS energies may be interpreted as a pure consequence of local energy-momentum conservation.

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