The anomalous chiral Lagrangian at order p 8
We derive the order p 8 Lagrangian of odd intrinsic parity for mesonic chiral perturbation theory, and provide the resulting operator basis in the supplementary material. Neglecting the non-zero singlet trace, we find 999 operators for a general number of quark flavours Nf , 705 for Nf = 3 and 92 for Nf = 2. Our numbers agree with those obtained through the Hilbert series approach in the literatur
