Alice Ohlson's research while affiliated with Lund University and other places

Publications (36)

Article
Full-text available
Recent theoretical explanations for how hydrodynamic-like flow can build up quickly in small collision systems (hydrodynamization) has led to a microscopic picture of flow building up in a gluon-dominated phase before chemical equilibrium between quarks and gluons has been attained. The goal of this contribution to Offshell-2021 is to explore conse...
Preprint
Recent theoretical explanations for how hydrodynamic-like flow can build up quickly in small collision systems (hydrodynamization) has led to a microscopic picture of flow building up in a gluon-dominated phase before chemical equilibrium between quarks and gluons has been attained. The goal of this contribution to Offshell-2021 is to explore conse...
Article
Full-text available
This report summarizes the presentations and discussions during the Rapid Reaction Task Force “Dynamics of critical fluctuations: Theory – phenomenology – heavy-ion collisions”, which was organized by the ExtreMe Matter Institute EMMI and held at GSI, Darmstadt, Germany in April 2019. We address the current understanding of the dynamics of critical...
Article
Full-text available
Event-by-event fluctuations of conserved charges – such as electric charge, strangeness, and baryon number – in ultrarelativistic heavy-ion collisions provide insight into the properties of the quark-gluon plasma and the QCD phase diagram. They can be related to the higher moments of the multiplicity distributions of identified particles, such as t...
Preprint
Correlations between particles separated by several units of pseudorapidity were discovered in high-multiplicity pp and p-Pb collisions at the LHC. These long-range structures observed in two-particle correlation functions are reminiscent of features seen in Pb-Pb collisions, where they are often viewed as a signature of collective behavior and the...
Preprint
Event-by-event fluctuations of conserved charges - such as electric charge, strangeness, and baryon number - in ultrarelativistic heavy-ion collisions provide insight into the properties of the quark-gluon plasma and the QCD phase diagram. They can be related to the higher moments of the multiplicity distributions of identified particles, such as t...
Article
We present an extension of the identity method initially introduced for particle yield fluctuation studies towards measurements of differential correlations. The extension is developed and illustrated in the context of measurements of the normalized two-particle cumulant R2 but is adaptable to any correlation measurements, including differential fl...
Preprint
We present an extension of the identity method initially introduced for particle yield fluctuation studies towards measurements of differential correlations. The extension is developed and illustrated in the context of measurements of the normalized two-particle cumulant $R_2$ but is adaptable to any correlation measurements, including differential...
Conference Paper
The event-by-event fluctuations of identified particles in ultrarelativistic nucleus-nucleus collisions give information about the state of matter created in these collisions as well as the phase diagram of nuclear matter. In this proceedings, we present the latest results from ALICE on the centrality and pseudorapidity dependence of net-proton flu...
Article
Full-text available
The presence of correlations between particles significantly separated in pseudorapidity in proton-proton and proton-nucleus collisions has raised questions about whether collective effects are observed in small collision systems as well as in heavy-ion collisions. The quantification of these long-range correlations by vn coefficients is of particu...
Article
Full-text available
At sufficiently high temperature and energy density, nuclear matter undergoes a transition to a phasein which quarks and gluons are not confined: the Quark-Gluon Plasma (QGP) [1]. Such an extremestate of strongly-interacting QCD (Quantum Chromo-Dynamics) matter is produced in the laboratorywith high-energy collisions of heavy nuclei, where an enhan...
Article
Full-text available
Measurements made by the ALICE Collaboration of single- and two-particle distributions in high-energy pp and p–Pb collisions are used to characterize the interactions in small collision systems, tune models of particle production in QCD, and serve as a baseline for heavy-ion observables. The measurements of charged-particle multiplicity density, 〈d...
Article
Full-text available
The discovery of correlations between particles separated by several units of pseudorapidity in high-multiplicity pp and p-Pb collisions, reminiscent of structures observed in Pb-Pb collisions, was a challenge to traditional ideas about collectivity in heavy ion collisions. In order to further explore long-range correlations and provide information...
Article
Full-text available
We report the results of the femtoscopic analysis of pairs of identical pions measured in p-Pb collisions at $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV. Femtoscopic radii are determined as a function of event multiplicity and pair momentum in three spatial dimensions. As in the pp collision system, the analysis is complicated by the presence of sizable back...

Citations

... Clearly, the notion of balance function can also be applied to charmness or bottomness. Recent measurements have shown that measurements of correlation functions of charmed hadrons are in fact possible but it remains to be established whether such observations can be formulated as genuine charm balance functions [26][27][28][29]. ...
... This study will complement the EIC program by providing additional information on the spatial structure of dense gluonic matter. In turn, this information will provide valuable input for the CBM experiment at FAIR in the study of the QCD phase diagram at low temperature and high baryon density [91], in particular, to inform theoretical models such as SMASH [92], AMPT [93], and hydrodynamics [94][95][96][97][98] that aim to describe the dynamical and transport properties of nuclear matter in such conditions. ...
... We usually will refer to the complete detector as EMCal (SM0- 19) and only treat the DCal as an independent detector when we intend to point out or illustrate a difference. An additional change of setup of the EMCal was introduced by the successive installation of the TRD detector modules [8], which are in front of the EMCal. The TRD modules provide additional material decreasing the yield of photons in some regions of the EMCal due to the additional photon conversions occurring in the TRD modules. ...
... Particle ratio fluctuations in AA collisions have been addressed in a number of studies, e.g., NA49 experiment in Pb-Pb collisions at E lab = 20 -158 A GeV [40] [42], and several others [33,36,38]. At LHC energies, the particle ratio fluctuations have been investigated by the ALICE experiment at ffiffi s p NN = 2:76 TeV only [43][44][45]. It has been reported [43] that ν dyn for ½π, K and ½p, K combinations acquires positive values irrespective of the centrality class, whereas, for ½π, p combination, the variable changes sign from positive to negative toward more peripheral collisions, indicating the difference in the production mechanisms involved of these pairs. ...
... We have demonstrated both reconstruction efficiency and purity corrections through a toy model simulations, and argued that one can tune the topological cut parameters so the best statistical significance is achieved for final results on higher-order cumulants. It would be also important to try the other method called "Identity Method" for an independent cross-check [27][28][29]. ...
... Experimental measurements of multiplicity distributions of identified hadrons are challenging because it is very difficult to identify a particle with sufficient precision. In this paper the Identity method [13][14][15][16][17][18][19] is employed to circumvent this problem. The Identity method has already been successfully used in the past by collaborations NA49 [8], NA61/SHINE [20], and ALICE [21][22][23]. ...
... The charm quark number fraction r h = 1 for D s , 1 − N Ds /N c ∼ 0.9 for the other charmed mesons, and 1 − N m /N c ∼ 0.6 for charmed baryons. [18] and ALICE [19,20] collaborations, the solid and dashed lines are respectively our sequential and simultaneous coalescence calculations. ...
... Fluctuations of net numbers of 's, kaons and pions are also being performed, and preliminary results were reported in Refs. [96][97][98]. Here we would like to discuss the behavior of these quantities within our approach. ...
... A study using the photon conversion method demonstrated that with this non-linearity correction, the π 0 mass in Monte Carlo (MC) simulations matches that in pp data within 1%. For pp collisions, an additional correction obtained from a photon conversion analysis was used to reduce the small remaining offset of the energy scale in data and MC simulations [60]. The energy resolution obtained from electron test beam data was about 15% at E cluster = 0.5 GeV and better ...
... Another way to obtain more information about the different charmonium production mechanisms is the analysis of the elliptic flow. J/ψ from (re)combined cc quarks should inherit the charm elliptic flow, which was observed in measurements of D-mesons [15]. The results at forward rapidity show a significant positive J/ψ elliptic flow in all studied p T bins, the measurement at mid-rapidity agrees within large statistical uncertainties with the one at forward rapidity [16]. ...