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A microscopic understanding of (anti)deuteron production in hadron–hadron collisions is the subject of many experimental and theoretical efforts in nuclear physics. This topic is also very relevant for astrophysics, since the rare production of antinuclei in our Universe could be a doorway to discover new physics. In this work, we describe a new coalescence afterburner for event generators based on the Wigner function formalism and we apply it to the (anti)deuteron case, taking into account a realistic particle emitting source. The model performance is validated using the EPOS and PYTHIA event generators applied to proton–proton collisions at the centre-of-mass energy s = 13  TeV, triggered for high multiplicity events, and the experimental data measured by ALICE in the same collision system. The model relies on the direct measurement of the particle emitting source carried out by means of nucleon–nucleon femtoscopic correlations in the same collision system and energy. The resulting model is used to predict deuteron differential spectra assuming different deuteron wavefunctions within the Wigner function formalism. The predicted deuteron spectra show a clear sensitivity to the choice of the deuteron wavefunction. The Argonne v 18 wavefunction provides the best description of the experimental data. This model can now be used to study the production of (anti)deuterons over a wide range of collision energies and be extended to heavier nuclei.

Antinuclei in our Galaxy may stem either from annihilation or decay of dark matter, or from collisions of cosmic rays with the interstellar medium, which constitute the background of indirect dark matter searches. Understanding the formation mechanism of (anti)nuclei is crucial for setting limits on their production in space. Coalescence models, which describe the formation of light nuclei from final-state interaction of nucleons, have been widely employed in high-energy collisions. In this work, we introduce ToMCCA ( To y M onte C arlo C oalescence A fterburner), which allows for detailed studies of the nuclear formation processes without the overload of general-purpose event generators. ToMCCA contains parameterizations of the multiplicity dependence of the transverse momentum distributions of protons and of the baryon-emitting source size, extracted from ALICE measurements in pp collisions at s = 5 - 13 TeV, as well as of the event multiplicity distributions, taken from the EPOS event generator. ToMCCA provides predictions of the deuteron transverse momentum distributions, with agreement of ∼ 5 % with the experimental data. The results of ToMCCA show that the coalescence mechanism in pp collisions depends only on the event multiplicity, not on the collision system or its energy. This allows the model to be utilized for predictions at lower center-of-mass collision energies, which are the most relevant for the production of antinuclei from processes related to dark matter. This model can also be extended to heavier nuclei as long as the target nucleus wavefunction and its Wigner function are known.

In recent years the femtoscopy technique has been used by the ALICE Collaboration in small colliding systems at the LHC to investigate the strong-interaction of hadron pairs in the low-energy regime. The extension of this technique to the study of many-body correlations aims to deliver in the next years the first experimental measurements of the genuine many-hadron interactions, provided that the contributions due to the lower order terms are properly accounted for. In this paper we present a method that allows to determine the residual lower order contributions to the three-body correlation functions, based on the cumulant decomposition approach and on kinematic transformations. A procedure to simulate genuine three-body correlations in three-baryon correlation functions is also developed. A qualitative study of the produced correlation signal is performed by varying the strength of the adopted three-body interaction model and comparisons with the expectations for the lower order contributions to the correlation function are shown. The method can be also applied to evaluate the combinatorial background in the two-body correlation functions, providing an improved statistical accuracy with respect to the standard techniques. The example of the contribution by the pK+K- channel to the recently measured pϕ correlation is discussed.

The aim of the AMADEUS collaboration is to provide experimental information on the low-energy strong interaction of antikaons with nucleons, exploiting the absorptions of low momentum K- mesons (pK∼ 127 MeV/c) produced at the DAΦNE collider, in the materials composing the KLOE detector setup, used as an active target. The K- single and multi-nucleon absorptions in light nuclei (4He and 12C) are investigated by reconstructing hyperon–pion, hyperon–nucleon/nucleus pairs, emitted in the final state of the reactions. In this paper the results obtained from the study of Λπ-, Λp and Λt correlated production are presented.

The AMADEUS Collaboration aims to provide unique experimental constraints to the antikaon-nucleon strong interaction in the regime of nonperturbative QCD. The K − nuclear captures, both at-rest and in-flight, are studied using the monochromatic low-momentum kaon beam ( p K ∼ 120 MeV/c) produced at the DAΦNE collider, interacting with the KLOE detector materials. The studies are performed by reconstructing the hyperon-pion and hyperonnucleon final states. In this work a brief description of AMADEUS results for Λπ − and Λ p final states is presented.

The AMADEUS collaboration is investigating the low-energy antikaon interactions with nucleons and nuclei, taking advantage of the lowmomentum antikaons beam provided by the DAΦNE collider at LNF-INFN. In this work a novel technique is outlined for the measurement of the hyperonnucleon two and three body scattering cross sections. The method consists in producing hyperons by antikaons atomic captures in light nuclear targets, and extrapolating the cross sections from the measurement of the yields of the corresponding elastic final state interactions of the hyperons. The feasibility of this kind of analyses is shown by comparison of calculated Σ 0 production in 4 He by K − absorption on three nucleons, with a sample of K −12 C absorption measured by AMADEUS in collaboration with KLOE. The feasibility of a dedicated high statistics measurement is discussed.

The aim of the AMADEUS experiment is to investigate the lowenergy antikaon interaction with nucleons and nuclei, exploiting the unique lowmomentum beam of kaons produced by the DAΦNE collider at LNF-INFN, to constrain hadronic nuclear physics models in the strangeness -1 sector. As a first step the data collected in 2004/2005 by the KLOE collaboration, consisting in a complex of K − absorptions in H, 4 He, 9 Be and 12 C, was analyzed, leading to the first invariant mass spectroscopic study with very low momentum (about 100 MeV) in-flight K − captures. A dedicated pure Carbon target was also implemented in the central region of the KLOE detector, providing a high statistic reference sample of pure at-rest K − nuclear interaction. The first measurement of the non-resonant transition amplitude$\\left| {{T_{{K^ - }n \\to \\Lambda {\\pi ^ - }}} \\right|$at$\\sqrt s = 33$MeV below the${\\text{\\bar KN}}$threshold is presented, in relation with the Λ(1405) properties studies.

We briefly report on the search for Deeply Bound Kaonic Nuclear States with AMADEUS in the Σ0p channel following K− absorption on 12C and outline future perspectives for this work.

We present the exclusive analysis of the reactions p+p [arrowright] Y + [Delta] super(++)/(p + [pi] super(+)) + K super(0), where Y stands for the [Lambda] or [Sigma] super(0) hyperon. The proton-proton measurement was performed with the HADES setup at GSI, Darmstadt, at a kinetic beam energy of 3.5 GeV. A dedicated sideband technique allows to reproduce the non-strange background and its kinematics in the selected data sample. Therefore, it is possible to obtain the background subtracted missing mass distribution MM(p[pi] super(+)[pi] super(+)[pi] super(-)), where we can separate the [Lambda] from the [Sigma] super(0) channel. From a Monte Carlo simulation of possible reactions we see contributions also by the reactions p + p [arrowright] [Sigma] super(+)/[Sigma](1385) super(+) + p + K super(0). The ongoing analysis should provide exclusive cross sections of the mentioned reactions and their angular distributions.