Strangeness $S = -2$ baryon-baryon interactions and femtoscopic correlation functions in covariant chiral effective field theory

Abstract

We study the baryon-baryon interactions with strangeness S = −2 and corresponding momentum correlation functions in leading order covariant chiral effective field theory. The relevant low energy constants are determined by fitting to the latest HAL QCD simulations, taking into account all the coupled channels. Extrapolating the so-obtained strong interactions to the physical point and considering both quantum statistical effects and the Coulomb interaction, we calculate the ΛΛ and Ξ − p correlation functions with a spherical Gaussian source and compare them with the recent experimental data. We find a remarkable agreement between our predictions and the experimental measurements without introducing any free parameters, which demonstrates the consistency between theory, experiment, and lattice QCD simulations. Finally, we predict the ΣΣ (I = 2) interaction and corresponding momentum correlation function, which rules out the existence of a bound state in this channel. Future experimental measurement of the predicted momentum correlation function will provide a non-trivial test of not only SU(3) flavor symmetry and its breaking but also covariant chiral effective field theory.

Strangeness ${S=-3}$ and ${-4}$ baryon-baryon interactions in chiral effective field theory

“…(See also Ref. [39] in this context.) There is no visible cusp for NLO16 because here the (𝐼 = 1) 3 𝑆 1 interaction is weaker/repulsive [7].…”

“…There a 𝑆 = −2 potential established from lattice QCD simulations by the HAL QCD Collaboration [38] has been employed. A recent study of Liu et al [39] uses a LO interaction based on covariant 𝜒EFT that was fitted to the phase shifts of the aforementioned HAL QCD potential. In this case similar 𝑅 values as those adopted by us for our NLO19 results seem to be preferred for getting agreement with the ALICE data and not those of [32].…”

An accurate relativistic chiral nucleon-nucleon interaction up to the next-to-next-to-leading order

“…At leading order (LO), the covariant scheme has been successfully employed to study the nucleon-nucleon scattering [22,[31][32][33][34] and hyperon-nucleon scattering [35][36][37][38][39][40][41]. In particular, We showed that in Ref.…”

3 S 1–3 D 1 coupled channel Λ c N interactions: chiral effective field theory versus lattice QCD

“…In the covariant ChEFT, Lorentz covariance is maintained by employing the covariant chiral Lagrangians, the full form of Dirac spinors, and the relativistic scattering equation (the Kadyshevsky equation). It has been shown that the covariant ChEFT approach can provide reasonable descriptions of octet baryon-octet baryon interactions already at LO, including all the systems from strangeness S = 0 to S = −4, at least in the low energy region [4][5][6][7][8][9][10][11][12][13][14]. 8 A recent study [11] showed that one could reproduce both the physical 1 S 0 and 3 S 1 -3 D 1 and the lattice QCD nucleon-nucleon partial wave phase shifts fairly well.…”

“…. More details about the covariant ChEFT approach can be found in [4][5][6][7][8][9][10][11][12][13][14][15].…”