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We search for excited charmed baryons in the ${\mathrm{\Lambda }}_c^{+}\eta$system using a data sample corresponding to an integrated luminosity of $980{\mathrm{fb}}^{-1}$. The data were collected by the Belle detector at the KEKB $e^{+}{e}^{-}$asymmetric-energy collider. No significant signals are found in the ${\mathrm{\Lambda }}_c^{+}\eta$mass spectrum, including the known ${\mathrm{\Lambda }}_c(2880{)}^{+}$and ${\mathrm{\Lambda }}_c(2940{)}^{+}$. Clear ${\mathrm{\Lambda }}_c(2880{)}^{+}$and ${\mathrm{\Lambda }}_c(2940{)}^{+}$signals are observed in the $p{D}^0$mass spectrum. We set upper limits at 90% credibility level on ratios of branching fractions of ${\mathrm{\Lambda }}_c(2880{)}^{+}$and ${\mathrm{\Lambda }}_c(2940{)}^{+}$decaying to ${\mathrm{\Lambda }}_c^{+}\eta$relative to ${\mathrm{\Sigma }}_c\left(2455\right)\pi$of $<0.13$for the ${\mathrm{\Lambda }}_c(2880{)}^{+}$and $<1.11$for the ${\mathrm{\Lambda }}_c(2940{)}^{+}$. We measure ratios of branching fractions of ${\mathrm{\Lambda }}_c(2880{)}^{+}$and ${\mathrm{\Lambda }}_c(2940{)}^{+}$decaying to $p{D}^0$relative to ${\mathrm{\Sigma }}_c\left(2455\right)\pi$of $0.75\pm 0.03\left(\mathrm{stat}\right)\pm 0.07\left(\mathrm{syst}\right)$for the ${\mathrm{\Lambda }}_c(2880{)}^{+}$and $3.59\pm 0.21\left(\mathrm{stat}\right)\pm 0.56\left(\mathrm{syst}\right)$for the ${\mathrm{\Lambda }}_c(2940{)}^{+}$. Published by the American Physical Society2024 

We report the results of the first search for Standard Model and baryon-number-violating two-body decays of the neutral $B$mesons to ${\mathrm{\Lambda }}^0$and ${\mathrm{\Omega }}_c^{(*)0}$using $711{\mathrm{fb}}^{-1}$of data collected at the $\mathrm{\Upsilon }\left(4S\right)$resonance with the Belle detector at the KEKB asymmetric-energy $e^{+}{e}^{-}$collider. We observe no evidence of signal from any such decays and set 95% confidence-level upper limits on the products of $B^0$and ${\overline{B}}^0$branching fractions for these two-body decays with $\mathcal{B}({\mathrm{\Omega }}_c^0\to {\pi }^{+}{\mathrm{\Omega }}^{-})$in the range between $9.5\times {10}^{-8}$and $31.2\times {10}^{-8}$. Published by the American Physical Society2024 

Abstract A series of data samples was collected with the Belle II detector at the SuperKEKB collider from March 2019 to June 2022. We determine the integrated luminosities of these data samples using three distinct methodologies involving Bhabha (), digamma (), and dimuon () events. The total integrated luminosity obtained with Bhabha, digamma, and dimuon events is (426.88 ± 0.03 ± 2.61) fb⁻¹, (429.28 ± 0.03 ± 2.62) fb⁻¹, and (423.99 ± 0.04 ± 3.83) fb⁻¹, where the first uncertainties are statistical and the second are systematic. The resulting total integrated luminosity obtained from the combination of the three methods is (427.87 ± 2.01) fb⁻¹. 

A bstract Using a data sample of 980 fb − 1 collected with the Belle detector at the KEKB asymmetric-energy e + e − collider, we study for the first time the singly Cabibbo-suppressed decays $$ {\Omega}_c^0\to {\Xi}^{-}{\pi}^{+} $$ Ω c 0 → Ξ − π + and Ω − K + and the doubly Cabibbo-suppressed decay $$ {\Omega}_c^0\to {\Xi}^{-}{K}^{+} $$ Ω c 0 → Ξ − K + . Evidence for an $$ {\Omega}_c^0 $$ Ω c 0 signal in the $$ {\Omega}_c^0 $$ Ω c 0 → Ξ − π + mode is reported with a significance of 4 . 5 σ including systematic uncertainties. The ratio of branching fractions to the normalization mode $$ {\Omega}_c^0 $$ Ω c 0 → Ω − π + is measured to be $$ \mathcal{B}\left({\Omega}_c^0\to {\Xi}^{-}{\pi}^{+}\right)/\mathcal{B}\left({\Omega}_c^0\to {\Omega}^{-}{\pi}^{+}\right)=0.253\pm 0.052\left(\textrm{stat}.\right)\pm 0.030\left(\textrm{syst}.\right). $$ B Ω c 0 → Ξ − π + / B Ω c 0 → Ω − π + = 0.253 ± 0.052 stat . ± 0.030 syst . . No significant signals of $$ {\Omega}_c^0\to {\Xi}^{-}{K}^{+} $$ Ω c 0 → Ξ − K + and Ω − K + modes are found. The upper limits at 90% confidence level on ratios of branching fractions are determined to be $$ \mathcal{B}\left({\Omega}_c^0\to {\Xi}^{-}{K}^{+}\right)/\mathcal{B}\left({\Omega}_c^0\to {\Omega}^{-}{\pi}^{+}\right)<0.070 $$ B Ω c 0 → Ξ − K + / B Ω c 0 → Ω − π + < 0.070 and $$ \mathcal{B}\left({\Omega}_c^0\to {\Omega}^{-}{K}^{+}\right)/\mathcal{B}\left({\Omega}_c^0\to {\Omega}^{-}{\pi}^{+}\right)<0.29. $$ B Ω c 0 → Ω − K + / B Ω c 0 → Ω − π + < 0.29 .