Speaker
Description
Nonleptonic hyperon transitions are studied in a relativistic framework of chiral perturbation theory ($\chi$PT). Previously, one-loop corrections to parity-violating and -conserving partial-wave amplitudes S and P have been computed in a nonrelativistic approach, focusing on the leading chiral logarithms [1]. This study concluded that a satisfying agreement with data and reasonable convergence is reachable for the S waves, but not for the P waves. In light of significant updates of asymmetry parameters on the experimental side (see [2] and references therein), we attempt a (re)calculation of one-loop corrections in relativistic $\chi$PT in the EOMS renormalization scheme [3, 4]. Following the suggestion of [5], the unknown low-energy constants are estimated using explicit resonances corresponding to the chiral order of the one-loop corrections. We present our results for the combined fit to S- and P-wave amplitudes, as well as the relative importance of the considered contributions, such as the role of resonances and decuplet baryons as intermediate states. To summarize, our goal is to provide an updated theoretical description of weak nonleptonic hyperon decays in $\chi$PT up to one-loop corrections, based on the most recent data and theoretical framework.
References
[1] E. Jenkins, Nucl. Phys. B 375 (1992), 561-581.
[2] Phys. Rev. D 105 (2022) 11, 116022.
[3] Phys. Rev. D 68 (2003), 056005.
[4] Front. Phys. 8 (2013), 328–348.
[5] Phys. Rev. D 59 (1999), 094025.
