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First measurement of the \( {\Lambda}_c^{+} \) → pη′ decay

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We present the first measurement of the branching fraction of the singly Cabibbo-suppressed (SCS) decay \( {\Lambda}_c^{+} \) → pη′ with η→ ηπ+π, using a data sample corresponding to an integrated luminosity of 981 fb1, collected by the Belle detector at the KEKB e+e asymmetric-energy collider. A significant \( {\Lambda}_c^{+} \) → pη′ signal is observed for the first time with a signal significance of 5.4σ. The relative branching fraction with respect to the normalization mode \( {\Lambda}_c^{+} \) → pKπ+ is measured to be

$$ \frac{\mathcal{B}\left({\Lambda}_c^{+}\to p\eta^{\prime}\right)}{\mathcal{B}\left({\Lambda}_c^{+}\to {pK}^{-}{\pi}^{+}\right)}=\left(7.54\pm 1.32\pm 0.73\right)\times {10}^{-3}, $$

where the uncertainties are statistical and systematic, respectively. Using the world-average value of \( \mathcal{B}\left({\Lambda}_c^{+}\to {pK}^{-}{\pi}^{+}\right) \) = (6.28 ± 0.32) × 102, we obtain

$$ \mathcal{B}\left({\Lambda}_c^{+}\to p\eta^{\prime}\right)=\left(4.73\pm 0.82\pm 0.46\pm 0.24\right)\times {10}^{-4}, $$

where the uncertainties are statistical, systematic, and from \( \mathcal{B}\left({\Lambda}_c^{+}\to {pK}^{-}{\pi}^{+}\right) \), respectively.


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The BELLE collaboration., Li, S.X., Cui, J.X. et al. First measurement of the \( {\Lambda}_c^{+} \) → pη′ decay. J. High Energ. Phys. 2022, 90 (2022).

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  • Branching fraction
  • e +-e Experiments
  • Charm Physics
  • Particle and Resonance Production