Speaker
Description
In our contribution, we will present recent theoretical developments designed to improve the modelling of quarkonia formation in ultrarelativistic heavy ions collisions as well as the systematic uncertainty resulting the semiclassical treatment which is often used in such situation. Accurate modeling and understanding of quarkonium production in such case requires a formalism that preserves the quantum properties of a microscopic $Q\bar{Q}$ system while treating the interaction of such pairs with the QGP. The open quantum system approach has recently emerged as one of the most fruitful schemes to meet such requirements. However, the quantum master equations obtained so far in this approach and currently used to make predictions for the upsilon suppression at RHIC and LHC are derived assuming a strict ordering between the QGP temperature and the energy gaps ($\Delta E$) of the upsilon bound states. This limits their predictive power as the QGP cooling interpolates between the quantum Brownian regime ($T>\Delta E$) and the quantum optical regime ($T<\Delta E$)
In our contribution, we derive and present a more general non-abelian quantum master equation of the Linblad type, which does not suffer from these limitations and thus allows to faithfully describe the quantum evolution of the $Q\bar{Q}$ pairs during the whole QGP evolution. Preliminary results will be shown showing the interpolating features of our equation between the two regimes. We also establish the contact with the QME previously obtained in the QBM and QO regimes and give some concrete perspectives for its efficient solution.
When dealing with charmonia production in URHIC, a full quantum treatment is out of reach due to the numerous ccbar pairs produced. Semiclassical approximation have been recently been derived in [1] and used f.i.in [2]. Obtaining an estimate of the systematic error attached to this approximation is of crucial importance to assess the agreement with experimental data. In the second part of the talk, we investigate the accuracy of the SC approximation by benchmarking the corresponding evolutions on the exact solutions derived with the QME for the case of a single c-cbar pair [3].
refs:
- J.-P. Blaizot and M.A. Escobedo, JHEP06(2018)034
- D.Y. Arrebato Villar et al., Phys.Rev.C 107 (2023) 5, 054913
- A. Daddi et al, https://arxiv.org/abs/2501.08772
