Constraints on New Physics from decays of polarized Λb⁰ baryons at the FCC-ee

The Z⁰ bosons produced in electron-positron collisions at the potential Future Circular Collider (FCC-ee) provide unique opportunities for flavour physics. The non-zero polarization of baryons produced in Z⁰ decays enables access to a much larger set of observables than at the LHC, where the baryons are produced unpolarized. This paper presents a toy angular analysis of Λb⁰→ Λ(→ pπ⁻)μ⁺μ⁻ decays using simulation samples of collisions at the FCC-ee reconstructed using the IDEA detector concept and assuming a dataset of 6× 10¹² Z⁰ bosons. While the statistical sensitivity achieved for individual angular observables is not expected to significantly exceed that from the LHCb Upgrade II experiment, the addition of the polarized observables leads to a significant improvement of the knowledge on the Wilson coefficients C₉ and C₁₀.