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1. Evidence of $h_b\left(2\mathrm{P}\right)\to \mathrm{\Upsilon }\left(1\mathrm{S}\right)\eta$ Decay and Search for $h_b(1\mathrm{P},2\mathrm{P})\to \mathrm{\Upsilon }\left(1\mathrm{S}\right){\pi }^0$ with the Belle Detector

   https://doi.org/10.1103/PhysRevLett.133.261901  

   Kovalenko, E; Adachi, I; Aihara, H; Asner, D M; Aushev, T; Ayad, R; Babu, V; Banerjee, Sw; Belous, K; Bennett, J; et al (December 2024, Physical Review Letters)

   We report the first evidence for the $h_b\left(2\mathrm{P}\right)\to \mathrm{\Upsilon }\left(1\mathrm{S}\right)\eta$transition with a significance of 3.5 standard deviations. The decay branching fraction is measured to be $\mathcal{B}\left[h_b\right(2\mathrm{P})\to \mathrm{\Upsilon }(1\mathrm{S}\left)\eta \right]=({7.1}_{-3.2}^{+3.7}\pm 0.8)\times {10}^{-3}$, which is noticeably smaller than expected. We also set upper limits on ${\pi }^0$transitions of $\mathcal{B}\left[h_b\right(2\mathrm{P})\to \mathrm{\Upsilon }(1\mathrm{S}\left){\pi }^0\right]<1.8\times {10}^{-3}$, and $\mathcal{B}\left[h_b\right(1\mathrm{P})\to \mathrm{\Upsilon }(1\mathrm{S}\left){\pi }^0\right]<1.8\times {10}^{-3}$, at the 90% confidence level. These results are obtained with a $131.4{\mathrm{fb}}^{-1}$data sample collected near the $\mathrm{\Upsilon }\left(5\mathrm{S}\right)$resonance with the Belle detector at the KEKB asymmetric-energy $e^{+}{e}^{-}$collider. Published by the American Physical Society2024 

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2. First Evidence for Direct $CP$ Violation in Beauty to Charmonium Decays

   https://doi.org/10.1103/PhysRevLett.134.101801  

   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 (March 2025, Physical Review Letters)

   The $CP$asymmetry and branching fraction of the Cabibbo-Kobayashi-Maskawa-suppressed decay $B^{+}\to J/\psi {\pi }^{+}$are precisely measured relative to the favored decay $B^{+}\to J/\psi K^{+}$using a sample of proton-proton collision data corresponding to an integrated luminosity of $5.4{\mathrm{fb}}^{-1}$recorded at a center-of-mass energy of 13 TeV during 2016–2018. The results of the $CP$asymmetry difference and branching fraction ratio are $\mathrm{\Delta }{\mathcal{A}}^{CP}\equiv {\mathcal{A}}^{CP}(B^{+}\to J/\psi {\pi }^{+})-{\mathcal{A}}^{CP}(B^{+}\to J/\psi K^{+})=(1.29\pm 0.49\pm 0.08)\times {10}^{-2}$, ${\mathcal{R}}_{\pi /K}\equiv \left[\mathcal{B}\right(B^{+}\to J/\psi {\pi }^{+})/\mathcal{B}(B^{+}\to J/\psi K^{+}\left)\right]=(3.852\pm 0.022\pm 0.018)\times {10}^{-2}$, where the first uncertainties are statistical and the second are systematic. A combination with previous LHCb results based on data collected at 7 and 8 TeV in 2011 and 2012 yields $\mathrm{\Delta }{\mathcal{A}}^{CP}=(1.42\pm 0.43\pm 0.08)\times {10}^{-2}$and ${\mathcal{R}}_{\pi /K}=(3.846\pm 0.018\pm 0.018)\times {10}^{-2}$. The combined $\mathrm{\Delta }{\mathcal{A}}^{CP}$value deviates from zero by 3.2 standard deviations, providing the first evidence for direct $CP$violation in the amplitudes of beauty decays to charmonium final states. © 2025 CERN, for the LHCb Collaboration2025CERN 

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3. Search for two-body $B$ meson decays to ${\mathrm{\Lambda }}^0$ and ${\mathrm{\Omega }}_c^{(*)0}$

   https://doi.org/10.1103/PhysRevD.110.L031102  

   Savinov, V; Adachi, I; Ahn, J K; Aihara, H; Asner, D M; Atmacan, H; Ayad, R; Banerjee, Sw; Bennett, J; Bessner, M; et al (August 2024, Physical Review D)

   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 

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4. First Determination of the Spin-Parity of ${\mathrm{\Xi }}_c(3055{)}^{+,0}$ Baryons

   https://doi.org/10.1103/PhysRevLett.134.081901  

   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, Physical Review Letters)

   The ${\mathrm{\Xi }}_b^{0(-)}\to {\mathrm{\Xi }}_c\left(3055{)}^{+\left(0\right)}\right(\to D^{+\left(0\right)}\mathrm{\Lambda }){\pi }^{-}$decay chains are observed, and the spin-parity of ${\mathrm{\Xi }}_c(3055{)}^{+\left(0\right)}$baryons is determined for the first time. The measurement is performed using proton-proton collision data at a center-of-mass energy of $\sqrt{s}=13\mathrm{TeV}$, corresponding to an integrated luminosity of $5.4{\mathrm{fb}}^{-1}$, recorded by the LHCb experiment between 2016 and 2018. The spin-parity of the ${\mathrm{\Xi }}_c(3055{)}^{+\left(0\right)}$baryons is determined to be $3/2^{+}$with a significance of more than $6.5\sigma$( $3.5\sigma$) compared to all other tested hypotheses. The up-down asymmetries of the ${\mathrm{\Xi }}_b^{0(-)}\to {\mathrm{\Xi }}_c(3055{)}^{+\left(0\right)}{\pi }^{-}$transitions are measured to be $-0.92\pm 0.10\pm 0.05$( $-0.92\pm 0.16\pm 0.22$), consistent with maximal parity violation, where the first uncertainty is statistical and the second is systematic. These results support the hypothesis that the ${\mathrm{\Xi }}_c(3055{)}^{+\left(0\right)}$baryons correspond to the first $D$-wave $\lambda$-mode excitation of the ${\mathrm{\Xi }}_c$flavor triplet. © 2025 CERN, for the LHCb Collaboration2025CERN 

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5. Study of light-meson resonances decaying to $K_{\mathrm{S}}^{0}K\pi$ in the $B\to \left(K_{\mathrm{S}}^{0}K\pi \right)K$ channels

   https://doi.org/10.1103/PhysRevD.111.092009  

   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 (May 2025, Physical Review D)

   A study is presented of $B^{+}\to K_{\mathrm{S}}^0{K}^{-}{\pi }^{+}{K}^{+}$and $B^{+}\to K_{\mathrm{S}}^0{K}^{+}{\pi }^{-}{K}^{+}$decays based on the analysis of proton-proton collision data collected with the LHCb detector at center-of-mass energies of 7, 8 and 13 TeV, corresponding to an integrated luminosity of $9{\mathrm{fb}}^{-1}$. The $K_{\mathrm{S}}^{0}K\pi$invariant-mass distributions of both $B^{+}$decay modes show, in the $m\left(K_{\mathrm{S}}^{0}K\pi \right)<1.85\mathrm{GeV}$mass region, large activity which is resolved using an amplitude analysis. A simple model, where $J^{PC}$amplitudes are described by multiple Breit-Wigner functions with appropriate angular distributions, provides a good description of the experimental data. In this approach a complex mixture of $J^{PC}=0^{-+}$, $1^{++}$and $1^{+-}$amplitudes is observed that is dominated by $\eta \left(1405\right)$, $\eta \left(1470\right)$, $\eta \left(1760\right)$, $f_1\left(1285\right)$, $f_1\left(1420\right)$and $h_1\left(1405\right)$resonances. The $K_{\mathrm{S}}^{0}K\pi$Dalitz plots are dominated by asymmetric crossing $K^{*}\overline{K}$bands which are different for the two $B^{+}$decay modes. This is due to a different interference pattern between the $1^{++}$and $1^{+-}$amplitudes in the two channels. Branching fractions are measured for each resonant contribution. © 2025 CERN, for the LHCb Collaboration2025CERN 

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