arXiv subjects

Maja Mackowiak-Pawlowska

Publications and source records attributed to Maja Mackowiak-Pawlowska.

10 recordsLinked to original sources

arXiv2021

Study of the phase diagram of strongly interacting matter in the NA61/SHINE experiment

NA61/SHINE (SPS Heavy Ion and Neutrino Experiment) is a fixed target experiment located at the CERN SPS. Its strong interactions program is devoted to study properties of the phase diagram of strongly interacting matter. For this goal the two-dimensional scan is performed by measurements of hadron production properties as a function of collision energy (13A - 158A GeV/$c$) and system size (p+p, p+Pb, Be+Be, Ar+Sc, Xe+La, Pb+Pb). This contribution presents new results on the onset of deconfinement - the transition between the state of hadronic matter and the quark-gluon plasma. Also, new results on fluctuations and correlations devoted to the search for the critical point of strongly interacting matter will be presented. Obtained results are compared with the available data from other experiments and from various theoretical models.

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arXiv2020

NA61/SHINE results on fluctuations and correlations at CERN SPS energies

The aim of the NA61/SHINE strong interaction programme is to explore the phase diagram of strongly interacting matter. The main physics goals are the study of the onset of deconfinement and the search for the critical point of strongly interacting matter. These goals are pursued by performing a beam momentum (13A -- 150/158A GeV/c) and system size (p+p, p+Pb, Be+Be, Ar+Sc, Xe+La, Pb+Pb) scan. This contribution presents new results from NA61/SHINE on fluctuations and correlations which include in particular quantum correlations, as well as multiplicity and net-charge fluctuations, proton density fluctuations and anisotropic collective flow. Obtained results are compared with other experiments and with model predictions.

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arXiv2018

Generalisation of the identity method for determination of high-order moments of multiplicity distributions with a software implementation

The incomplete particle identification limits the experimentally-available phase space region for identified particle analysis. This problem affects ongoing fluctuation and correlation studies including the search for the critical point of strongly interacting matter performed on SPS and RHIC accelerators. In this paper we provide a procedure to obtain $n$-th order moments of the multiplicity distribution using the identity method, generalising previously published solutions for $n=2$ and $n=3$. Moreover, we present an open source software implementation of this computation, called \textit{Idhim}, that allows one to obtain the true moments of identified particle multiplicity distributions from the measured ones provided the response function of the detector is known.

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arXiv2017

Multi moment cancellation of participant fluctuations

We summarize the new method for the correction of participant fluctuations in high energy nucleus-nucleus collisions. It allows to estimate a fluctuation baseline in comparison to a useful signal. In particular cases of a weak signal compared to baseline, it allows to cancel the baseline contribution from participants.

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arXiv2017

Multi moment cancellation of participant fluctuations - MMCP method

We propose a new way to correct for finite centrality bin width effect i.e. participant fluctuations in fluctuation analysis in high energy nucleus-nucleus collisions. The MMCP method allows to separate participant fluctuations and obtain fluctuations from one participant - a source - from a combination of the experimentally measured first four moments. The EPOS model is used for the numerical check of the MMCP for the net electric charge fluctuations in the forward rapidity region in Ar+Sc reactions at beam momentum 150 GeV/c. We show that using the existing methods - decreasing a centrality bin width, or using the Centrality Bin Width Correction procedure, one may still leave some residual participant fluctuations in the sample. Moreover, we show that the Centrality Bin Width Correction procedure may alter the fluctuation measures. The most important advantage of the MMCP is it's precision even when the amount of measured events does not allow to decrease the centrality bin width, or the experimental determination of participants is difficult, e.g. in collider experiments. Even for the largest centrality bin in the considered case, $c=0-20\%$, the relative error of the MMCP for the scaled variance of a source is below 2\%. It is especially important in determination of the base line of the fluctuations in the search for the QCD Critical Point and the signals of the QCD phase transition.

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arXiv2017

Recent results from NA61/SHINE

NA61/SHINE at the CERN SPS is a fixed-target experiment pursuing a rich physics program including measurements for heavy ion, neutrino and cosmic ray physics. The main goal of the strong interactions program is to study the properties of the onset of deconfinement and to search for the signatures of the critical point. In this contribution the latest NA61/SHINE results on particle spectra as well as on fluctuations and correlations from p+p, Be+Be, and Ar+Sc energy scans will be presented. The NA61 measurements will be compared with world data and with model predictions.

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arXiv2016

Higher order moments of net-charge and multiplicity distributions in p+p interactions at SPS energies from NA61/SHINE

NA61/SHINE at the CERN SPS is a fixed-target experiment pursuing a rich physics program including measurements for heavy ion, neutrino and cosmic ray physics. The main goal of the ion program is to study the properties of the onset of deconfinement and to search for the signatures of the critical point. A specific property of the critical point, the increase in the correlation length, makes fluctuations its basic signal. Higher order moments of suitable observables are of special interest as they are more sensitive to the correlation length than typically studied second order moments. In this contribution preliminary results on higher order fluctuations of negatively charged hadron multiplicity and net-charge in p+p interactions are shown. The new data are compared with model predictions.

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arXiv2016

NA61/SHINE results on fluctuations and correlations in p+p and Be+Be interactions at CERN SPS energies

The aim of the NA61/SHINE strong interaction program is to explore the phase diagram of strongly interacting matter. The main physics goals are the study of the onset of deconfinement and the search for the critical point of strongly interacting matter. These goals are pursued by performing a beam momentum (13$A$ - 158$A$ GeV/c) and system size (p+p, p+Pb, Be+Be, Ar+Sc, Xe+La) scan. This contribution presents results on transverse momentum and multiplicity fluctuations from the Be+Be and p+p energy scan. Also, results on two-particle correlations in pseudorapidity and azimuthal angle obtained in p+p interactions will be shown. The influence of conservation laws and resonance decays on multiplicity and chemical fluctuations of identified particles in p+p interactions will be discussed. Obtained results will be compared with data from other experiments and with model predictions.

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arXiv2015

Latest results from the NA61/SHINE beam energy scan with p+p and Be+Be collisions

The NA61/SHINE experiment aims to discover the critical point of strongly interacting matter and study the properties of the onset of deconfinement by measurements of hadron production properties in proton-proton, proton-nucleus and nucleus-nucleus interactions in the CERN SPS energy range. This contribution presents results on the energy dependence of hadron spectra and yields as well as on fluctuations and two-particle correlations in p+p and centrality selected Be+Be collisions. In particular, the energy dependence of the signal of deconfinement, the "horn", observed in central Pb+Pb collisions is compared with the corresponding results from p+p interactions. Also string-hadronic models are tested using hadron spectra and fluctuations measured in p+p interactions. Results on fluctuations (multiplicity and transverse momentum) are presented as a function of the collision energy for Be+Be and p+p collisions in search for the critical point of strongly interacting matter.

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arXiv2012

New results from fluctuation analysis in NA49 at the CERN SPS

The exploration of the phase diagram of strongly interacting matter, particularly the study of the phase transition from hadronic to partonic matter and the search for a hypothetical critical endpoint of the first order transition line, is one of the most challenging tasks in present heavy ion physics. In this talk new results on chemical (particle ratio), transverse momentum, multiplicity and azimuthal angle fluctuations will be presented. We also discuss their connection to the onset of deconfinement and to the critical endpoint.

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