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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. Observation of the ${\mathrm{\Xi }}_b^{-}\to \psi \left(2S\right){\mathrm{\Xi }}^{-}$ decay and studies of the ${\mathrm{\Xi }}_b(5945{)}^0$ baryon in proton-proton collisions at $\sqrt{s}=13\mathrm{TeV}$

   https://doi.org/10.1103/PhysRevD.110.012002  

   Hayrapetyan, A; Tumasyan, A; Adam, W; Andrejkovic, J W; Bergauer, T; Chatterjee, S; Damanakis, K; Dragicevic, M; Hussain, P S; Jeitler, M; et al (July 2024, Physical review)

   The first observation of the decay ${\mathrm{\Xi }}_b^{-}\to \psi \left(2S\right){\mathrm{\Xi }}^{-}$ and measurement of the branching ratio of ${\mathrm{\Xi }}_b^{-}\to \psi \left(2S\right){\mathrm{\Xi }}^{-}$ to ${\mathrm{\Xi }}_b^{-}\to J/\psi {\mathrm{\Xi }}^{-}$ are presented. The $J/\psi$ and $\psi \left(2S\right)$ mesons are reconstructed using their dimuon decay modes. The results are based on proton-proton colliding beam data from the LHC collected by the CMS experiment at $\sqrt{s}=13\mathrm{TeV}$ in 2016–2018, corresponding to an integrated luminosity of $140{\mathrm{fb}}^{-1}$ . The branching fraction ratio is measured to be $\mathcal{B}\left({\mathrm{\Xi }}_b^{-}\to \psi \left(2S\right){\mathrm{\Xi }}^{-}\right)/\mathcal{B}\left({\mathrm{\Xi }}_b^{-}\to J/\psi {\mathrm{\Xi }}^{-}\right)=0.84_{-0.19}^{+0.21}\left(\mathrm{stat}\right)\pm 0.10\left(\mathrm{syst}\right)\pm 0.02\left(\mathcal{B}\right)$ , where the last uncertainty comes from the uncertainties in the branching fractions of the charmonium states. New measurements of the ${\mathrm{\Xi }}_b(5945{)}^0$ baryon mass and natural width are also presented, using the ${\mathrm{\Xi }}_b^{-}{\pi }^{+}$ final state, where the ${\mathrm{\Xi }}_b^{-}$ baryon is reconstructed through the decays $J/\psi {\mathrm{\Xi }}^{-}$ , $\psi \left(2S\right){\mathrm{\Xi }}^{-}$ , $J/\psi \mathrm{\Lambda }{K}^{-}$ , and $J/\psi {\mathrm{\Sigma }}^0{K}^{-}$ . Finally, the fraction of ${\mathrm{\Xi }}_b^{-}$ baryons produced from ${\mathrm{\Xi }}_b(5945{)}^0$ decays is determined. © 2024 CERN, for the CMS Collaboration2024CERN 

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3. 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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4. Measurement of ${\mathrm{\Omega }}_{\mathrm{c}}^0$ baryon production and branching-fraction ratio $\mathrm{BR}({\mathrm{\Omega }}_{\mathrm{c}}^0\to {\mathrm{\Omega }}^{-}{\mathrm{e}}^{+}{\nu }_{\mathrm{e}})/\mathrm{BR}({\mathrm{\Omega }}_{\mathrm{c}}^0\to {\mathrm{\Omega }}^{-}{\pi }^{+})$ in $pp$ collisions at $\sqrt{s}=13\mathrm{TeV}$

   https://doi.org/10.1103/PhysRevD.110.032014  

   Acharya, S; Adamová, D; Agarwal, A; Aglieri_Rinella, G; Aglietta, L; Agnello, M; Agrawal, N; Ahammed, Z; Ahmad, S; Ahn, S U; et al (August 2024, Physical Review D)

   The inclusive production of the charm-strange baryon ${\mathrm{\Omega }}_{\mathrm{c}}^0$ is measured for the first time via its semileptonic decay into ${\mathrm{\Omega }}^{-}{\mathrm{e}}^{+}{\nu }_{\mathrm{e}}$ at midrapidity ( $\left|y\right|<0.8$ ) in proton-proton (pp) collisions at the center-of-mass energy $\sqrt{s}=13\mathrm{TeV}$ with the ALICE detector at the LHC. The transverse momentum ( $p_{\mathrm{T}}$ ) differential cross section multiplied by the branching ratio is presented in the interval $2<p_{\mathrm{T}}<12\mathrm{GeV}/c$ . The branching-fraction ratio $\mathrm{BR}({\mathrm{\Omega }}_{\mathrm{c}}^0\to {\mathrm{\Omega }}^{-}{\mathrm{e}}^{+}{\nu }_{\mathrm{e}})/\mathrm{BR}({\mathrm{\Omega }}_{\mathrm{c}}^0\to {\mathrm{\Omega }}^{-}{\pi }^{+})$ is measured to be $1.12\pm 0.22$ (stat) $\pm 0.27$ (syst). Comparisons with other experimental measurements, as well as with theoretical calculations, are presented. © 2024 CERN, for the ALICE Collaboration2024CERN 

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5. Search for charmed baryons in the ${\mathrm{\Lambda }}_c^{+}\eta$ system and measurement of the branching fractions of ${\mathrm{\Lambda }}_c(2880{)}^{+}$ and ${\mathrm{\Lambda }}_c(2940{)}^{+}$ decaying to ${\mathrm{\Lambda }}_c^{+}\eta$ and $p{D}^0$ relative to ${\mathrm{\Sigma }}_c\left(2455\right)\pi$

   https://doi.org/10.1103/PhysRevD.110.032021  

   Li, S X; Shen, C P; Adachi, I; Ahn, J K; Aihara, H; Asner, D M; Atmacan, H; Aushev, T; Ayad, R; Banerjee, Sw; et al (August 2024, Physical Review D)

   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 

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