Model-independent evidence for $J/\ddot{I}ˆp$ contributions to $\hat{I}{›}_b^0\to J/\ddot{I}ˆp{K}^{-}$ decays

Abstract

The data sample of $\hat{I}{›}_b^0\to J/\ddot{I}ˆp{K}^{-}$ decays acquired with the LHCb detector from 7 and 8~TeV $pp$ collisions, corresponding to an integrated luminosity of 3 fb${}^{-1}$, is inspected for the presence of $J/\ddot{I}ˆp$ or $J/\ddot{I}ˆK^{-}$ contributions with minimal assumptions about $K^{-}p$ contributions. It is demonstrated at more than 9 standard deviations that $\hat{I}{›}_b^0\to J/\ddot{I}ˆp{K}^{-}$ decays cannot be described with $K^{-}p$ contributions alone, and that $J/\ddot{I}ˆp$ contributions play a dominant role in this incompatibility. These model-independent results support the previously obtained model-dependent evidence for $P_c^{+}\to J/\ddot{I}ˆp$ charmonium-pentaquark states in the same data sample.

21 pages, 12 figures (including the supplemental section added at the end)