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1. Observation of the Open-Charm Tetraquark Candidate $T_{cs0}^{*}(2870{)}^0$ in the $B^{-}\to D^{-}{D}^0{K}_S^0$ Decay

   https://doi.org/10.1103/PhysRevLett.134.101901  

   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)

   An amplitude analysis of $B^{-}\to D^{-}{D}^0{K}_S^0$ decays is performed using proton-proton collision data, corresponding to an integrated luminosity of $9{\mathrm{fb}}^{-1}$ , collected with the LHCb detector at center-of-mass energies of 7, 8, and 13 TeV. A resonant structure of spin-parity $0^{+}$ is observed in the $D^0{K}_S^0$ invariant-mass spectrum with a significance of $5.3\sigma$ . The mass and width of the state, modeled with a Breit-Wigner line shape, are determined to be $2883\pm 11\pm 8\mathrm{MeV}/c^2$ and ${87}_{-47}^{+22}\pm 17\mathrm{MeV}$ , respectively, where the first uncertainties are statistical and the second systematic. These properties and the quark content are consistent with those of the open-charm tetraquark candidate $T_{cs0}^{*}(2870{)}^0$ observed previously in the $D^{+}{K}^{-}$ final state of the $B^{-}\to D^{-}{D}^{+}{K}^{-}$ decay. This result confirms the existence of the $T_{cs0}^{*}(2870{)}^0$ state in a new decay mode. The $T_{cs1}^{*}(2900{)}^0$ state, reported in the $B^{-}\to D^{-}{D}^{+}{K}^{-}$ decay, is also searched for in the $D^0{K}_S^0$ invariant-mass spectrum of the $B^{-}\to D^{-}{D}^0{K}_S^0$ decay, without finding evidence for it. © 2025 CERN, for the LHCb Collaboration2025CERN 

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2. First measurement of $D_{s1}\left(1^{+}\right)(2536{)}^{+}$ and $D_{s2}^{*}\left(2^{+}\right)(2573{)}^{+}$ production in proton-proton collisions at $\sqrt{s}=13\mathrm{TeV}$ at the LHC

   https://doi.org/10.1103/PhysRevD.111.112005  

   Acharya, S; Agarwal, A; Aglieri_Rinella, G; Aglietta, L; Agnello, M; Agrawal, N; Ahammed, Z; Ahmad, S; Ahn, S U; Ahuja, I; et al (June 2025, Physical Review D)

   The production yields of the orbitally excited charm-strange mesons ${\mathrm{D}}_{\mathrm{s}1}\left(1^{+}\right)(2536{)}^{+}$ and ${\mathrm{D}}_{\mathrm{s}2}^{*}\left(2^{+}\right)(2573{)}^{+}$ were measured for the first time in proton-proton (pp) collisions at a center-of-mass energy of $\sqrt{s}=13\mathrm{TeV}$ with the ALICE experiment at the LHC. The ${\mathrm{D}}_{\mathrm{s}1}^{+}$ and ${\mathrm{D}}_{\mathrm{s}2}^{*+}$ mesons were measured at midrapidity ( $\left|y\right|<0.5$ ) in minimum-bias and high-multiplicity pp collisions in the transverse-momentum interval $2<p_{\mathrm{T}}<24\mathrm{GeV}/c$ . Their production yields relative to the ${\mathrm{D}}_{\mathrm{s}}^{+}$ ground-state yield were found to be compatible between minimum-bias and high-multiplicity collisions, as well as with previous measurements in ${\mathrm{e}}^{\pm }\mathrm{p}$ and ${\mathrm{e}}^{+}{\mathrm{e}}^{-}$ collisions. The measured ${\mathrm{D}}_{\mathrm{s}1}^{+}/{\mathrm{D}}_{\mathrm{s}}^{+}$ and ${\mathrm{D}}_{\mathrm{s}2}^{*+}/{\mathrm{D}}_{\mathrm{s}}^{+}$ yield ratios are described by statistical hadronization models and can be used to tune the parameters governing the production of excited charm-strange hadrons in Monte Carlo generators, such as 8. 

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3. Measurement of the time-integrated $CP$ asymmetry in $D^0\to K_S^0{K}_S^0$ decays using Belle and Belle II data

   https://doi.org/10.1103/PhysRevD.111.012015  

   Adachi, I; Aggarwal, L; Ahmed, H; Aihara, H; Akopov, N; Aloisio, A; Althubiti, N; Anh_Ky, N; Asner, D M; Atmacan, H; et al (January 2025, Physical Review D)

   We measure the time-integrated $CP$ asymmetry in $D^0\to K_S^0{K}_S^0$ decays reconstructed in $e^{+}{e}^{-}\to c\overline{c}$ events collected by the Belle and Belle II experiments. The corresponding data samples have integrated luminosities of 980 and $428{\mathrm{fb}}^{-1}$ , respectively. The $D^0$ decays are required to originate from the $D^{*+}\to D^0{\pi }^{+}$ decay, which determines the charm flavor at production time. A control sample of $D^0\to K^{+}{K}^{-}$ decays is used to correct for production and detection asymmetries. The result, $(-1.4\pm 1.3\left(\mathrm{stat}\right)\pm 0.1\left(\mathrm{syst}\right))\%$ , is consistent with previous determinations and with $CP$ symmetry. Published by the American Physical Society2025 

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4. Measurement of the branching fractions and longitudinal polarizations of $B_{\left(s\right)}^0\to K^{*0}{\overline{K}}^{*0}$ decays

   https://doi.org/10.1103/cd57-xr8f  

   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 2026, Physical Review D)

   A time- and flavor-integrated amplitude analysis of $B^0$ and $B_s^0$ decays to the $\left(K^{+}{\pi }^{-}\right)\left(K^{-}{\pi }^{+}\right)$ final state in the $K^{*}\left(892{)}^0{\overline{K}}^{*}\right(892{)}^0$ region is presented, using $pp$ collision data recorded with the LHCb detector in 2011–2018, corresponding to an integrated luminosity of $9{\mathrm{fb}}^{-1}$ . The branching fractions of the $B^0$ and $B_s^0$ decays are measured relative to the $B^0\to D^{-}{\pi }^{+}$ and $B_s^0\to D_s^{-}{\pi }^{+}$ modes, respectively. The corresponding longitudinal polarization fractions are found to be $f_L^d=0.600\pm 0.022\pm 0.017$ and $f_L^s=0.159\pm 0.010\pm 0.007$ , where the uncertainties are statistical and systematic, respectively. The theory-motivated ratio of the squared $B_s^0$ to $B^0$ longitudinally polarized decay amplitudes is found to be $L_{K^{*0}{\overline{K}}^{*0}}=4.92\pm 0.55\pm 0.48\pm 0.02\pm 0.10$ , where the uncertainties are statistical, systematic, due to uncertainty of external mass and lifetime measurements, and due to knowledge of the fragmentation fraction ratio, respectively. This confirms the previously reported tension between experimental determinations and theoretical predictions of longitudinal polarization in $B\to VV$ decays at the level of 4.4 standard deviations. 

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5. Model-independent measurement of $D^0\text{−}{\overline{D}}^0$ mixing parameters in $D^0\to K_S^0{\pi }^{+}{\pi }^{-}$ decays at Belle and Belle II

   https://doi.org/10.1103/7p5s-f9qp  

   Adachi, I; Aggarwal, L; Ahmed, H; Aihara, H; Akopov, N; Aloisio, A; Althubiti, N; Anh_Ky, N; Asner, D M; Atmacan, H; et al (June 2025, Physical Review D)

   We perform a model-independent measurement of the $D^0\text{−}{\overline{D}}^0$ mixing parameters using samples of $e^{+}{e}^{-}$ -collision data collected by the Belle and Belle II experiments that have integrated luminosities of $951{\mathrm{fb}}^{-1}$ and $408{\mathrm{fb}}^{-1}$ , respectively. Approximately $2.05\times {10}^6$ neutral $D$ mesons are reconstructed in the $D^0\to K_{\mathrm{S}}^0{\pi }^{+}{\pi }^{-}$ channel, with the neutral $D$ flavor tagged by the charge of the pion in the $D^{*+}\to D^0{\pi }^{+}$ decay. Assuming charge-parity symmetry, the mixing parameters are measured to be $x=(4.0\pm 1.7\pm 0.4)\times {10}^{-3}$ and $y=(2.9\pm 1.4\pm 0.3)\times {10}^{-3}$ , where the first uncertainties are statistical and the second systematic. The results are consistent with previous determinations. 

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