Publication
Observation of $$ {\Lambda}_b^0 $$ → D+pπ−π− and $$ {\Lambda}_b^0 $$ → D*+pπ−π− decays
Publisher:
Springer Science and Business Media LLC
Date:
03-2022
DOI:
10.1007/JHEP03(2022)153
Abstract: The multihadron decays $$ {\\Lambda}_b^0 $$ Λ b 0 → D + pπ−π− and $$ {\\Lambda}_b^0 $$ Λ b 0 → D * + pπ−π− are observed in data corresponding to an integrated luminosity of 3 fb − 1 , collected in proton-proton collisions at centre-of-mass energies of 7 and 8 TeV by the LHCb detector. Using the decay $$ {\\Lambda}_b^0 $$ Λ b 0 → $$ {\\Lambda}_c^{+} $$ Λ c + π + π − π − as a normalisation channel, the ratio of branching fractions is measured to be $$ \\frac{\\mathcal{B}\\left({\\Lambda}_b^0\\to {D}^{+}p{\\pi}^{-}{\\pi}^{-}\\right)}{\\mathcal{B}\\left({\\Lambda}_b^0\\to {\\Lambda}_c^0{\\pi}^{+}{\\pi}^{-}{\\pi}^{-}\\right)}\\times \\frac{\\mathcal{B}\\left({D}^{+}\\to {K}^{-}{\\pi}^{+}{\\pi}^{+}\\right)}{\\mathcal{B}\\left({\\Lambda}_c^0\\to {pK}^{-}{\\pi}^{-}\\right)}=\\left(5.35\\pm 0.21\\pm 0.16\\right)\\%, $$ B Λ b 0 → D + p π − π − B Λ b 0 → Λ c 0 π + π − π − × B D + → K − π + π + B Λ c 0 → pK − π − = 5.35 ± 0.21 ± 0.16 % , where the first uncertainty is statistical and the second systematic. The ratio of branching fractions for the $$ {\\Lambda}_b^0 $$ Λ b 0 → D *+ pπ − π − and $$ {\\Lambda}_b^0 $$ Λ b 0 → D + pπ − π − decays is found to be $$ \\frac{\\mathcal{B}\\left({\\Lambda}_b^0\\to {D}^{\\ast +}p{\\pi}^{-}{\\pi}^{-}\\right)}{\\mathcal{B}\\left({\\Lambda}_b^0\\to {D}^{+}p{\\pi}^{-}{\\pi}^{-}\\right)}\\times \\left(\\mathcal{B}\\left({D}^{\\ast +}\\to {D}^{+}{\\pi}^0\\right)+\\mathcal{B}\\left({D}^{\\ast +}\\to {D}^{+}\\gamma \\right)\\right)=\\left(61.3\\pm 4.3\\pm 4.0\\right)\\%. $$ B Λ b 0 → D ∗ + p π − π − B Λ b 0 → D + p π − π − × B D ∗ + → D + π 0 + B D ∗ + → D + γ = 61.3 ± 4.3 ± 4.0 % .