2024/05/27 by Gino Isidori, Isidori, Gino, Zachary Polonsky +3
Mathematics · Physics and Astronomy · #Advanced Mathematical Physics Problems #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions
paper · pdf · doi:10.48550/arxiv.2405.17551
openalex publication_date 2024/05/27 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
We analyze B0 → K0 ℓℓ long-distance contributions induced by the rescattering of a pair of charmed and charmed-strange mesons. We present an explicit estimate of these contributions using an effective description in terms of hadronic degrees of freedom, supplemented by data on the B0 → D^*Ds (D^*sD) transition in order to reproduce the corresponding discontinuity in the B0 → K0 ℓℓ amplitude. The D^* Ds (D^*s D) K vertex is estimated using heavy-hadron chiral perturbation theory, obtaining an accurate description of the whole rescattering process in the low-recoil (or high-q2) limit. We also present an extrapolation to the whole kinematical region introducing hadronic form factors. The explicit estimate of the leading D^*Ds (D^*sD) intermediate state leads to a long-distance amplitude which does not exceed a few percent relative to the short-distance one. The consequences of this result for the extraction of the short-distance coefficient C9 are discussed.