Study of two-body doubly charmful baryonic B decays with SU(3) flavor symmetry

Abstract

Within the framework of SU(3) flavor symmetry, we investigate two-body doubly charmful baryonic $$ B\to {\textbf{B}}_c{\overline{\textbf{B}}}_c^{\prime } $$ B → B c B ¯ c ′ decays, where $$ {\textbf{B}}_c{\overline{\textbf{B}}}_c^{\prime } $$ B c B ¯ c ′ represents the anti-triplet charmed dibaryon. We determine the SU(3)f amplitudes and calculate $$ \mathcal{B}\left({B}^{-}\to {\Xi}_c^0{\overline{\Xi}}_c^{-}\right)=\left({3.4}_{-0.9}^{+1.0}\right)\times {10}^{-5} $$ B B − → Ξ c 0 Ξ ¯ c − = 3.4 − 0.9 + 1.0 × 10 − 5 and $$ \mathcal{B}\left({\overline{B}}_s^0\to {\Lambda}_c^{+}{\overline{\Xi}}_c^{-}\right)=\left({3.9}_{-1.0}^{+1.2}\right)\times {10}^{-5} $$ B B ¯ s 0 → Λ c + Ξ ¯ c − = 3.9 − 1.0 + 1.2 × 10 − 5 induced by the single W-emission configuration. We find that the W-exchange amplitude, previously neglected in studies, needs to be taken into account. It can cause a destructive interfering effect with the W-emission amplitude, alleviating the significant discrepancy between the theoretical estimation and experimental data for $$ \mathcal{B}\left({\overline{B}}^0\to {\Lambda}_c^{+}{\overline{\Lambda}}_c^{-}\right) $$ B B ¯ 0 → Λ c + Λ ¯ c − . To test other interfering decay channels, we calculate $$ \mathcal{B}\left({\overline{B}}_s^0\to {\Xi}_c^{0\left(+\right)}{\overline{\Xi}}_c^{0\left(+\right)}\right)=\left({3.0}_{-1.1}^{+1.4}\right)\times {10}^{-4} $$ B B ¯ s 0 → Ξ c 0 + Ξ ¯ c 0 + = 3.0 − 1.1 + 1.4 × 10 − 4 and $$ \mathcal{B}\left({\overline{B}}^0\to {\Xi}_c^0{\overline{\Xi}}_c^0\right)=\left({1.5}_{-0.6}^{+0.7}\right)\times {10}^{-5} $$ B B ¯ 0 → Ξ c 0 Ξ ¯ c 0 = 1.5 − 0.6 + 0.7 × 10 − 5 . We estimate non-zero branching fractions for the pure W-exchange decay channels, specifically $$ \mathcal{B}\left({\overline{B}}_s^0\to {\Lambda}_c^{+}{\overline{\Lambda}}_c^{-}\right)=\left({8.1}_{-1.5}^{+1.7}\right)\times {10}^{-5} $$ B B ¯ s 0 → Λ c + Λ ¯ c − = 8.1 − 1.5 + 1.7 × 10 − 5 and $$ \mathcal{B}\left({\overline{B}}^0\to {\Xi}_c^{+}{\overline{\Xi}}_c^{-}\right)=\left(3.0\pm 0.6\right)\times {10}^{-6} $$ B B ¯ 0 → Ξ c + Ξ ¯ c − = 3.0 ± 0.6 × 10 − 6 . Additionally, we predict $$ \mathcal{B}\left({B}_c^{+}\to {\Xi}_c^{+}{\overline{\Xi}}_c^0\right)=\left({2.8}_{-0.7}^{+0.9}\right)\times {10}^{-4} $$ B B c + → Ξ c + Ξ ¯ c 0 = 2.8 − 0.7 + 0.9 × 10 − 4 and $$ \mathcal{B}\left({B}_c^{+}\to {\Lambda}_c^{+}{\overline{\Xi}}_c^0\right)=\left({1.6}_{-0.4}^{+0.5}\right)\times {10}^{-5} $$ B B c + → Λ c + Ξ ¯ c 0 = 1.6 − 0.4 + 0.5 × 10 − 5 , which are accessible to experimental facilities such as LHCb.