Strangeness S=−2 baryon-baryon interactions using chiral effective field theory

We derive the leading order strangeness S=−2 baryon-baryon interactions in chiral effective field theory. The potential consists of contact terms without derivatives and of one-pseudoscalar-meson exchanges. The contact terms and the couplings of the pseudoscalar mesons to the baryons are related via SU(3)f symmetry to the S=−1 hyperon-nucleon channels. We show that the chiral effective field theory predictions with natural values for the low-energy constants agree with the experimental information in the S=−2 sector.