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1. Search for prompt production of pentaquarks in charm hadron final states

   https://doi.org/10.1103/PhysRevD.110.032001  

   Aaij, R; Abdelmotteleb, A_S W; Abellan_Beteta, C; Abudinén, F; Ackernley, T; Adeva, B; Adinolfi, M; Adlarson, P; Afsharnia, H; Agapopoulou, C; et al (August 2024, Physical Review D)

   A search for hidden-charm pentaquark states decaying to a range of ${\mathrm{\Sigma }}_c\overline{D}$ and ${\mathrm{\Lambda }}_c^{+}\overline{D}$ final states, as well as doubly charmed pentaquark states to ${\mathrm{\Sigma }}_{c}D$ and ${\mathrm{\Lambda }}_c^{+}D$ , is made using samples of proton-proton collision data corresponding to an integrated luminosity of $5.7{\mathrm{fb}}^{-1}$ recorded by the LHCb detector at $\sqrt{s}=13\mathrm{TeV}$ . Since no significant signals are found, upper limits are set on the pentaquark yields relative to that of the ${\mathrm{\Lambda }}_c^{+}$ baryon in the ${\mathrm{\Lambda }}_c^{+}\to p{K}^{-}{\pi }^{+}$ decay mode. The known pentaquark states are also investigated, and their signal yields are found to be consistent with zero in all cases. © 2024 CERN, for the LHCb Collaboration2024CERN 

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2. Measurement of ${\mathrm{\Lambda }}_b^0$ , ${\mathrm{\Lambda }}_c^{+}$ , and $\mathrm{\Lambda }$ Decay Parameters Using ${\mathrm{\Lambda }}_b^0\to {\mathrm{\Lambda }}_c^{+}{h}^{-}$ Decays

   https://doi.org/10.1103/PhysRevLett.133.261804  

   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 (December 2024, Physical Review Letters)

   A comprehensive study of the angular distributions in the bottom-baryon decays ${\mathrm{\Lambda }}_b^0\to {\mathrm{\Lambda }}_c^{+}{h}^{-}(h=\pi ,K)$ , followed by ${\mathrm{\Lambda }}_c^{+}\to \mathrm{\Lambda }{h}^{+}$ with $\mathrm{\Lambda }\to p{\pi }^{-}$ or ${\mathrm{\Lambda }}_c^{+}\to p{K}_{\mathrm{S}}^0$ decays, is performed using a data sample of proton-proton collisions corresponding to an integrated luminosity of $9{\mathrm{fb}}^{-1}$ collected by the LHCb experiment at center-of-mass energies of 7, 8, and 13 TeV. The decay parameters and the associated charge-parity ( $CP$ ) asymmetries are measured, with no significant $CP$ violation observed. For the first time, the ${\mathrm{\Lambda }}_b^0\to {\mathrm{\Lambda }}_c^{+}{h}^{-}$ decay parameters are measured. The most precise measurements of the decay parameters $\alpha$ , $\beta$ , and $\gamma$ are obtained for ${\mathrm{\Lambda }}_c^{+}$ decays and an independent measurement of the decay parameters for the strange-baryon $\mathrm{\Lambda }$ decay is provided. The results deepen our understanding of weak decay dynamics in baryon decays. © 2024 CERN, for the LHCb Collaboration2024CERN 

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3. 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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4. Study of ${\mathrm{\Lambda }}_b^0$ and ${\mathrm{\Xi }}_b^0$ Decays to $\mathrm{\Lambda }{h}^{+}{h}^{\prime -}$ and Evidence for $CP$ Violation in ${\mathrm{\Lambda }}_b^0\to \mathrm{\Lambda }{K}^{+}{K}^{-}$ Decays

   https://doi.org/10.1103/PhysRevLett.134.101802  

   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)

   A study of ${\mathrm{\Lambda }}_b^0$ and ${\mathrm{\Xi }}_b^0$ decays to $\mathrm{\Lambda }{h}^{+}{h}^{\prime -}$ ( $h^{(\prime )}=\pi ,K$ ) is performed using $pp$ collision data collected by the LHCb experiment during LHC Runs 1–2, corresponding to an integrated luminosity of $9{\mathrm{fb}}^{-1}$ . The branching fractions for these decays are measured using the ${\mathrm{\Lambda }}_b^0\to {\mathrm{\Lambda }}_c^{+}(\to \mathrm{\Lambda }{\pi }^{+}){\pi }^{-}$ decay as a control channel. The decays ${\mathrm{\Lambda }}_b^0\to \mathrm{\Lambda }{\pi }^{+}{\pi }^{-}$ and ${\mathrm{\Xi }}_b^0\to \mathrm{\Lambda }{K}^{-}{\pi }^{+}$ are observed for the first time. For decay modes with sufficient signal yields, $CP$ asymmetries are measured in the full and localized regions of the final-state phase space. Evidence is found for $CP$ violation in the ${\mathrm{\Lambda }}_b^0\to \mathrm{\Lambda }{K}^{+}{K}^{-}$ decay, interpreted as originating primarily from an asymmetric ${\mathrm{\Lambda }}_b^0\to N^{*+}{K}^{-}$ decay amplitude. The measured $CP$ asymmetries for other decays are compatible with zero. © 2025 CERN, for the LHCb Collaboration2025CERN 

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5. 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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