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1. Search for CP violation in $$ {D}_{(s)}^{+}\to {K}_S^0{K}^{-}{\pi}^{+}{\pi}^{+} $$ decays using triple and quadruple products

   https://doi.org/10.1007/JHEP04(2025)036  

   Aggarwal, L; Ahmed, H; Aihara, H; Akopov, N; Aloisio, A; Althubiti, N; Anh_Ky, N; Asner, D M; Atmacan, H; Aushev, V; et al (April 2025, Journal of High Energy Physics)

   A<sc>bstract</sc> We perform the first search forCPviolation in$$ {D}_{(s)}^{+}\to {K}_S^0{K}^{-}{\pi}^{+}{\pi}^{+} $$ $D_{\left(s\right)}^{+}\to K_S^0{K}^{-}{\pi }^{+}{\pi }^{+}$decays. We use a combined data set from the Belle and Belle II experiments, which studye⁺e⁻collisions at center-of-mass energies at or near the Υ(4S) resonance. We use 980 fb⁻¹of data from Belle and 428 fb⁻¹of data from Belle II. We measure sixCP-violating asymmetries that are based on triple products and quadruple products of the momenta of final-state particles, and also the particles’ helicity angles. We obtain a precision at the level of 0.5% for$$ {D}^{+}\to {K}_S^0{K}^{-}{\pi}^{+}{\pi}^{+} $$ $D^{+}\to K_S^0{K}^{-}{\pi }^{+}{\pi }^{+}$decays, and better than 0.3% for$$ {D}_s^{+}\to {K}_S^0{K}^{-}{\pi}^{+}{\pi}^{+} $$ $D_s^{+}\to K_S^0{K}^{-}{\pi }^{+}{\pi }^{+}$decays. No evidence ofCPviolation is found. Our results for the triple-product asymmetries are the most precise to date for singly-Cabibbo-suppressedD⁺decays. Our results for the other asymmetries are the first such measurements performed for charm decays. 

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2. Measurement of CP asymmetries and branching-fraction ratios for B± → DK± and Dπ± with D → $$ {K}_{\textrm{S}}^0 $$K±π∓ using Belle and Belle II data

   https://doi.org/10.1007/JHEP09(2023)146  

   Adachi, I; Aggarwal, L; Aihara, H; Akopov, N; Aloisio, A; Anh_Ky, N; Asner, D M; Aushev, T; Aushev, V; Aversano, M; et al (September 2023, Journal of High Energy Physics)

   A<sc>bstract</sc> We measureCPasymmetries and branching-fraction ratios forB^±→ DK^±andDπ^±decays withD →$$ {K}_{\textrm{S}}^0 $$ $K_S^0$K^±π^∓, whereDis a superposition ofD⁰and$$ \overline{D} $$ $\overline{D}$⁰. We use the full data set of the Belle experiment, containing 772×10⁶$$ B\overline{B} $$ $B\overline{B}$pairs, and data from the Belle II experiment, containing 387 × 10⁶$$ B\overline{B} $$ $B\overline{B}$pairs, both collected in electron-positron collisions at the Υ(4S) resonance. Our results provide model-independent information on the unitarity triangle angleϕ₃. 

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3. Measurement of the CKM angle γ in B± → DK*(892)± decays

   https://doi.org/10.1007/JHEP02(2025)113  

   Aaij, R; Abdelmotteleb, A_S W; Abellan_Beteta, C; Abudinén, F; Ackernley, T; Adefisoye, A A; Adeva, B; Adinolfi, M; Adlarson, P; Agapopoulou, C; et al (February 2025, Journal of High Energy Physics)

   A<sc>bstract</sc> Measurements ofCPobservables and the CKM angleγare performed inB^±→DK^*(892)^±decays, whereDrepresents a superposition ofD⁰and$$ {\overline{D}}^0 $$ ${\overline{D}}^0$states, using the LHCb dataset collected during Run 1 (2011–2012) and Run 2 (2015–2018). A study of this channel is presented with theDmeson reconstructed in two-body final statesK^±π^∓,K⁺K⁻andπ⁺π⁻; four-body final statesK^±π^∓π^±π^∓andπ⁺π⁻π⁺π⁻; and three-body final states$$ {K}_{\textrm{S}}^0{\pi}^{+}{\pi}^{-} $$ $K_S^0{\pi }^{+}{\pi }^{-}$and$$ {K}_{\textrm{S}}^0{K}^{+}{K}^{-} $$ $K_S^0{K}^{+}{K}^{-}$. This analysis includes the first observation of the suppressedB^±→[π^±K^∓]_DK^*±andB^±→[π^±K^∓π^±π^∓]_DK^*±decays. The combined result givesγ= (63±13)°. 

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4. Measurement of the e+e− → $$ {B}_s^0{\overline{B}}_s^0X $$ cross section in the energy range from 10.63 to 11.02 GeV using inclusive $$ {D}_s^{+} $$ and D0 production

   https://doi.org/10.1007/JHEP08(2023)131  

   Zhukova, V; Mizuk, R; Adachi, I; Aihara, H; Al_Said, S; Asner, D M; Atmacan, H; Aulchenko, V; Aushev, T; Ayad, R; et al (August 2023, Journal of High Energy Physics)

   A<sc>bstract</sc> We report the first measurement of the inclusivee⁺e⁻→$$ b\overline{b} $$ $b\overline{b}$→$$ {D}_s^{\pm } $$ $D_s^{\pm }$Xande⁺e⁻→$$ b\overline{b} $$ $b\overline{b}$→ D⁰/$$ {\overline{D}}^0 $$ ${\overline{D}}^0$Xcross sections in the energy range from 10.63 to 11.02 GeV. Based on these results, we determineσ(e⁺e⁻→$$ {B}_s^0{\overline{B}}_s^0 $$ $B_s^0{\overline{B}}_s^0$X) andσ(e⁺e⁻→$$ B\overline{B} $$ $B\overline{B}$X) in the same energy range. We measure the fraction of$$ {B}_s^0 $$ $B_s^0$events at Υ(10860) to bef_s= ($$ {22.0}_{-2.1}^{+2.0} $$ ${22.0}_{-2.1}^{+2.0}$)%. We determine also the ratio of the$$ {B}_s^0 $$ $B_s^0$inclusive branching fractions$$ \mathcal{B} $$ $B$($$ {B}_s^0 $$ $B_s^0$→ D⁰/$$ {\overline{D}}^0 $$ ${\overline{D}}^0$X)/$$ \mathcal{B} $$ $B$($$ {B}_s^0 $$ $B_s^0$→$$ {D}_s^{\pm } $$ $D_s^{\pm }$X) = 0.416 ± 0.018 ± 0.092. The results are obtained using the data collected with the Belle detector at the KEKB asymmetric-energye⁺e⁻collider. 

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5. Measurement of the energy dependence of the e+e− → $$ B\overline{B} $$, $$ B{\overline{B}}^{\ast } $$, and $$ {B}^{\ast }{\overline{B}}^{\ast } $$ cross sections at Belle II

   https://doi.org/10.1007/JHEP10(2024)114  

   Adachi, I; Aggarwal, L; Ahmed, H; Aihara, H; Akopov, N; Aloisio, A; Althubiti, N; Anh_Ky, N; Asner, D M; Atmacan, H; et al (October 2024, Journal of High Energy Physics)

   A<sc>bstract</sc> We report measurements of thee⁺e⁻→$$ B\overline{B} $$ $B\overline{B}$,$$ B{\overline{B}}^{\ast } $$ $B{\overline{B}}^{\ast }$, and$$ {B}^{\ast }{\overline{B}}^{\ast } $$ $B^{\ast }{\overline{B}}^{\ast }$cross sections at four energies, 10653, 10701, 10746 and 10805 MeV, using data collected by the Belle II experiment. We reconstruct oneBmeson in a large number of hadronic final states and use its momentum to identify the production process. In the first 2 – 5 MeV above$$ {B}^{\ast }{\overline{B}}^{\ast } $$ $B^{\ast }{\overline{B}}^{\ast }$threshold, thee⁺e⁻→$$ {B}^{\ast }{\overline{B}}^{\ast } $$ $B^{\ast }{\overline{B}}^{\ast }$cross section increases rapidly. This may indicate the presence of a pole close to the threshold. 

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