arXiv subjects

Juan Torres-Rincon

Publications and source records attributed to Juan Torres-Rincon.

4 recordsLinked to original sources

arXiv2026

Non-Markovian heavy-quark equilibration and equilibrium correlation function in a thermal medium

We compute the charm-quark current-current correlation function within the Langevin framework and extract the heavy-quark diffusion coefficient using the Green--Kubo formula. The formalism is further extended to evaluate the correlation function using a generalized Langevin equation that incorporates memory effects via an exponentially decaying memory kernel. We find that while memory effects qualitatively modify the transient structure of the current correlations, the value of the transport coefficient remains unchanged in the non-relativistic limit. In addition, we investigate heavy-quark thermalization in the presence of memory and compare the non-equilibrium solution of a generalized Fokker--Planck equation with the one obtained from the generalized Langevin equation in the non-relativistic limit. We also consider the relativistic version of the correlated noise case and observe that memory effects can give rise to a damped, oscillatory equilibration of the heavy quark in a non-Markovian bath.

hep-ph↗

arXiv2026

Kaon-deuteron correlation function from an effective field theory approach

We present a study of femtoscopic correlation functions for $K^{-}d$ and $K^{+}d$ pairs, and compare our results with recent measurements by the ALICE Collaboration in both Pb-Pb and high-multiplicity $pp$ collisions. The kaon-deuteron wave functions are derived from scattering amplitudes using a unitarized chiral effective theory model describing the elementary interactions of $K^{\pm}$ mesons with nucleons. We then evaluate the $K^{\pm}d$ strong scattering amplitudes by solving the Faddeev equations within two distinct frameworks: the Impulse Approximation and the Fixed Center Approximation, which accounts for multiple scatterings. We also incorporate the long-range Coulomb effects between the kaon and the deuteron. We show that the $K^{-}d$ correlation function exhibits large sensitivity to both the size of the emitting source and the relative momentum of the pair, being heavily influenced by rescattering processes. In contrast, the $K^{+}d$ correlation function is dominated by the weakly repulsive $K^{+}N$ interaction, showing deviations from purely Coulombic behavior only at small emission source sizes. Our predictions are in agreement with the ALICE experimental data, and also with the energy-shift and width of the $1s$ level of the kaonic deuterium preliminary results from the SIDDHARTA 2 Collaboration.

nucl-th↗

arXiv2024

Formation, dissociation and regeneration of charmonia within microscopic Langevin simulations

We present a microscopic dynamical model to study the formation, dissociation, and recombination processes of charmonium states in a heat bath at constant temperature and volume. Within this classical approach, heavy quarks are described as Brownian particles in a background medium of light constituents and can therefore be modeled by a Fokker-Planck equation with constant transport coefficients, which is then implemented through relativistic Langevin simulations. The heavy quarks interact classically via a Coulomb-like screened potential to form a bound state if the relative energy of the pair becomes negative. Dissociation of bound states is possible as a result of screening effects on the potential as well as through scatterings with plasma particles. We demonstrate the full equilibration of the system and show that the resulting equilibrium charmonium yields are in accordance with the Statistical Hadronization Model.

hep-ph↗

arXiv2024

$p \Omega$ femtoscopy using baryon-baryon effective potentials

We have generated an updated version of the $p\Omega$ potential for low-energy interactions based on an effective field theory approach at leading order. This potential, together with other potentials based either on different parametrizations or lattice QCD calculations, have been used to solve the Schr\"odinger equation numerically, obtaining the scattering wave functions for different values of the relative momentum. Using these wave functions, we have computed the $p \Omega$ femtoscopic correlation functions, comparing the results with those published by the ALICE collaboration.

nucl-th↗