Présidents de session
Track1-LF
- Huan Huang (UCLA Physics and Astronomy)
Track1-LF
- Domenico Elia (INFN Bari, Italy)
Track1-LF
- Alexander Philipp Kalweit (CERN)
Track1-LF
- Rene Bellwied (University of Houston)
Track1-LF
- Katarzyna Grebieszkow (Warsaw University of Technology, Faculty of Physics)
Heavy-ion collision experiments produce the deconfined state of nuclear matter, the quark-gluon plasma (QGP). At QGP temperatures, the vacuum condensate is expected to melt leading to the restoration of the approximate chiral symmetry of QCD. As the plasma expands and cools, the chiral condensates are formed again. So far, concrete experimental evidence of this widely expected phenomena has...
It is well known that isospin symmetry is fulfilled to a good approximation in strong interactions, as confirmed in low-energy scattering experiments and in mass spectra of both light and heavy hadrons. In collisions of nuclei with an equal number of protons and neutrons, isospin symmetry imposes that the number of produced charged kaons should equal the number of neutral ones. The NA61/SHINE...
The first measurements of femtoscopic correlations with the particle-pair combinations $\pi^{\pm}$ $K^0_S$ in pp collisions at $\sqrt{s}$ = 13 TeV are reported by ALICE. It is shown that it is possible to study the elusive $K^*_0(700)$ particle that has been considered a tetraquark candidate for over forty years. Boson source parameters and final-state interaction parameters are extracted by...
The strangeness content of the final state in ultrarelativistic heavy ion collisions has been studied through measurements of kaons, $\Lambda$, Ξ and $\Omega$ baryons in pp, pA and AA collisions. $\Sigma$ baryons contain a single strange quark and form a triplet, with the charge (+, 0, -) depending on the light quark content. In a thermal model scenario, these states are abundant enough to...
Recent developments on a deep learning feed-forward network for estimating elliptic flow ($v_2$) coefficients in heavy-ion collisions have shown us the prediction power of this technique. The success of the model is mainly the estimation of $v_2$ from final state particle kinematic information and learning the centrality and the transverse momentum ($p_T$) dependence of $v_2$. The deep...
In any relativistic quantum field theory such as Quantum Chromodynamics or Electroweak theory, the interactions are invariant under the combined operation of Charge conjugation (C), Parity transformation (P) and Time reversal (T). One of the consequences of this (CPT) symmetry is that particles and their corresponding antiparticles must have exactly same mass. While the mass difference bewteen...
Light hadrons are considerably produced in high-energy heavy-ion collisions and provide a wealth of information about properties of created QCD medium and reaction dynamics. These include, in particular, the implications of collective flow in small and large systems
and the impact of recombination on baryon and strangeness enhancement. The system size dependence studies of different...
Measurements of light-flavour particle production in small collision systems at the LHC energies have shown the onset of features (e.g. collective evolution, strangeness enhancement) that resemble what is typically observed in nucleus-nucleus collisions. These features were shown at the LHC to scale with the charged-particle multiplicity independently on the collision system and energy.
New...
Strange hadron production provides information about the hadronization process in high-energy hadron collisions. Strangeness enhancement has been interpreted as a signature of quark-gluon plasma formation in heavy-ion collisions, and recent observations of strangeness enhancement in small collisions systems have challenged conventional hadronization models. With its forward geometry and...
The angular correlation between (multi-)strange and associated identified hadrons is measured in pp collisions with the ALICE detector to give insight into the particle production mechanisms and balancing of quantum numbers at the microscopic level. These measurements are expected to be sensitive to whether strangeness is produced through string breaking or in a thermal production scenario....
The pseudorapidity dependence of charged particle production provides information on the partonic structure of the colliding hadrons and is, in particular at LHC energies, sensitive to non-linear QCD evolution in the initial state. For Run3, ALICE has increased its pseudorapidity coverage to track charged particles over a wider range of −3.6 < $\eta$ < 2 combining the measurement from the...
Ultra-peripheral collisions (UPCs) provide a unique environment to study pomeron- and photon-induced reactions with heavy nuclei. These interactions can produce a wide range of final state particles, from light vector mesons to heavy quarkonia, and probe potentially exotic phenomena. With a fast DAQ, full particle ID, and the ability to reconstruct very low pt particles, LHCb is uniquely...
Measurements of high-multiplicity pp and pA collisions at LHC energies have revealed that these small colliding systems exhibit quark-gluon plasma-like features, such as collective behaviour and strangeness enhancement. A method to narrow down the origin of this phenomenon is to relate the strangeness production to Multi-Parton Interactions (MPIs). Although the MPIs cannot be measured...
Well established measurements of high-multiplicity proton-proton (pp) and proton-lead (p-Pb) collisions at the LHC have revealed that small collision systems show the onset of phenomena typical of heavy-ion collisions. Some of these signatures, such as strangeness enhancement and collective flow, suggest that light-flavor hadron production arises from a set of complex mechanisms whose relative...
This talk presents unprecedented correlation measurements involving Λ, Ξ, kaons and pions obtained by ALICE in pp collisions at $\sqrt{s}$ = 13 TeV. Several measurements are presented for the first time, constituting new experimental constraints on the S = −1, −2 meson-baryon interactions and the nature of exotic states. The strong interactions involving mesons and baryons with strangeness...
Femtoscopic analysis using a two-particle correlation function has attracted significant interest as a method to study hadron interactions. According to the Koonin-Pratt formula [1, 2], the correlation function is interpreted as a convolution of the source function, which reflects the dynamics of the nuclear collisions, and the square of the relative wave function, which reflects the quantum...
Femtoscopy is a powerful technique used to investigate the emission source and interaction potential between pairs of particles. The two-particle correlation function, which reveals valuable information about the space-time evolution of the emitting source and final state interaction, is the primary observable of interest. A detailed knowledge of hyperon-nucleon (Y-N) interaction is important...
Using data collected in high-multiplicity pp collisions at 13 TeV with the ALICE detector during the Run 2 period of the LHC, the femtoscopy technique has been successfully employed to extend the boundaries of known hadron-hadron interactions to the S=-3 sector and to initiate studies of charmed and three-body systems. The key element of these analyzes is the precise modeling of the common...
Collective effects similar to those in Pb-Pb collisions have been observed in smaller systems, such as pp and p-Pb collisions. Among these is the increase of the strange to non-strange hadron ratio with charged-particle multiplicity density. Understanding these effects requires a detailed description of the production mechanisms of strange hadrons, which is obscured by large uncertainties in...
Charged kaons – mesons containing one (anti)strange quark – are predicted to be good probes of the Equation of State (EoS) of nuclear matter and possible changes of basic properties of kaons (like mass and decay constant) in hot and dense nuclear matter [1, 2]. These effects can be studied by comparing measured data to model calculations and the anisotropies of the azimuthal angle (flow) are...
The LHCb SMOG system provides the unique opportunity to study strangeness production in fixed-target collisions at the LHC. Studies of trangeness production in high-energy fixed-target collisions provides information on hadronization and serve as important inputs to models of particle production in cosmic rays. Recent results on strangeness production in fixed-target proton-nucleus collisions...
The conventional picture of baryon number is that each valence quark inside a baryon carries 1/3 unit of baryon number. However, an alternative picture exists where the center of a Y-shaped topology of gluon fields, called the baryon junction, carries 1 unit of baryon number. Previous analysis of net-proton yield at mid-rapidity from the Beam Energy Scan program phase-I (BES-I) at RHIC showed...
Strange hadrons have been suggested as sensitive probes for the medium properties of the nuclear matter created in heavy-ion collisions. At few-GeV collision energies, the formed medium is dense and baryon-rich due to the baryon stopping. Since strange hadrons are produced near or below the threshold, their yields, especially the excitation function of multi-strange (anti-)hyperons, may...
NA61/SHINE is a large-acceptance fixed-target experiment located at the CERN SPS. The main physics goals of the NA61/SHINE ion program are the study of the properties of the onset of deconfinement and the search for signatures of the critical point of strongly interacting matter. These goals are pursued by performing an energy (beam momentum 13$A$-158$A$ GeV/$c$) and system size (p+p, p+Pb,...
