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1. Constraints on Symmetric Dark Matter from Neutron Star Capture and Collapse

   https://doi.org/10.1103/5wsg-z61z  

   Liu, Yuxin; Liu, Zhen; Pospelov, Maxim; Reddy, Sanjay (May 2026, Physical Review Letters)

   Dark matter (DM) models with a conserved particle-antiparticle number, $n_{\chi }-n_{\tilde{\chi }}$ , and the asymmetry in the cosmological abundance $n_{\chi }\ne n_{\tilde{\chi }}$ , are known to be challenged by the existence of old neutron stars (NSs), as the sufficient accumulation of DM will lead to the collapse of NSs into black holes. We demonstrate that the applicability of these constraints is much wider and covers models with symmetric populations of DM, $n_{\chi }=n_{\tilde{\chi }}$ , as the process of DM capture regulated by a nucleon-DM scattering can be inherently asymmetric, ${\sigma }_{\chi n}\ne {\sigma }_{\tilde{\chi }n}$ . The asymmetry is induced by the interference of different types of $\chi \text{−}n$ interactions, provided that their combination is odd under charge conjugation in the DM sector, $C_{\chi }$ , and even under combined parity $P_{\chi +n}$ . We provide a complete analysis of DM-nucleon bilinear $\chi \text{−}n$ interactions and find that this asymmetry is very generic. Using canonical NS parameters and local DM halo inputs, we exclude spin-averaged scattering cross sections down to ${\sigma }_{n\chi }\gtrsim {10}^{-46}{\mathrm{cm}}^2$ at DM mass $m_{\chi }\lesssim {10}^{10}\mathrm{GeV}$ for the maximally asymmetric capture rate and show that the constraints persist down to very small values of the cross-section asymmetry, $\mathcal{A}=({\sigma }_{\chi n}-{\sigma }_{\tilde{\chi }n})/({\sigma }_{\chi n}+{\sigma }_{\tilde{\chi }n})\gtrsim {10}^{-5}$ . 

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2. Simultaneous Probe of the Charm and Bottom Quark Yukawa Couplings Using $t\overline{t}H$ Events

   https://doi.org/10.1103/9nwb-splk  

   Hayrapetyan, A; Makarenko, V; Tumasyan, A; Adam, W; Andrejkovic, J W; Benato, L; Bergauer, T; Dragicevic, M; Giordano, C; Hussain, P S; et al (January 2026, Physical Review Letters)

   A search for the standard model Higgs boson decaying to a charm quark-antiquark pair, $H\to c\overline{c}$ , produced in association with a top quark-antiquark pair ( $t\overline{t}H$ ) is presented. The search is performed with data from proton-proton collisions at $\sqrt{s}=13\mathrm{TeV}$ , corresponding to an integrated luminosity of $138{\mathrm{fb}}^{-1}$ . Advanced machine learning techniques are employed for jet flavor identification and event classification. The Higgs boson decay to a bottom quark-antiquark pair is measured simultaneously and the observed $t\overline{t}H\left(H\to b\overline{b}\right)$ event rate relative to the standard model expectation is ${0.91}_{-0.22}^{+0.26}$ . The observed (expected) upper limit on the product of production cross section and branching fraction $\sigma \left(t\overline{t}H\right)\mathcal{B}(H\to c\overline{c})$ is 0.11 (0.13) pb at 95% confidence level, corresponding to 7.8 (8.7) times the standard model prediction. When combined with the previous search for $H\to c\overline{c}$ via associated production with a $W$ or $Z$ boson, the observed (expected) 95% confidence interval on the Higgs-charm Yukawa coupling modifier, ${\kappa }_c$ , is $\left|{\kappa }_c\right|<3.5$ (2.7), the most stringent constraint to date. 

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3. Test of lepton flavor universality with a measurement of $R\left(D^{*}\right)$ using hadronic $B$ tagging at the Belle II experiment

   https://doi.org/10.1103/PhysRevD.110.072020  

   Adachi, I; Adamczyk, K; Aggarwal, L; Ahmed, H; Aihara, H; Akopov, N; Aloisio, A; Anh_Ky, N; Asner, D M; Atmacan, H; et al (October 2024, Physical Review D)

   The ratio of branching fractions $R\left(D^{*}\right)=\mathcal{B}(\overline{B}\to D^{*}{\tau }^{-}{\overline{\nu }}_{\tau })/\mathcal{B}(\overline{B}\to D^{*}{\ell }^{-}{\overline{\nu }}_{\ell })$ , where $\ell$ is an electron or muon, is measured using a Belle II data sample with an integrated luminosity of $189{\mathrm{fb}}^{-1}$ at the SuperKEKB asymmetric-energy $e^{+}{e}^{-}$ collider. Data is collected at the $\mathrm{\Upsilon }\left(4\mathrm{S}\right)$ resonance, and one $B$ meson in the $\mathrm{\Upsilon }\left(4\mathrm{S}\right)\to B\overline{B}$ decay is fully reconstructed in hadronic decay modes. The accompanying signal $B$ meson is reconstructed as $\overline{B}\to D^{*}{\tau }^{-}{\overline{\nu }}_{\tau }$ using leptonic $\tau$ decays. The normalization decay, $\overline{B}\to D^{*}{\ell }^{-}{\overline{\nu }}_{\ell }$ , produces the same observable final-state particles. The ratio of branching fractions is extracted in a simultaneous fit to two signal-discriminating variables in both channels and yields $R\left(D^{*}\right)={0.262}_{-0.039}^{+0.041}\left(\mathrm{stat}{)}_{-0.032}^{+0.035}\right(\mathrm{syst})$ . This result is consistent with the current world average and with Standard Model predictions. Published by the American Physical Society2024 

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4. First Measurement of ${\nu }_e$ and ${\overline{\nu }}_e$ Charged-Current Single Charged-Pion Production Differential Cross Sections on Argon Using the MicroBooNE Detector

   https://doi.org/10.1103/sfrz-c8m9  

   Abratenko, P; Andrade_Aldana, D; Arellano, L; Asaadi, J; Ashkenazi, A; Balasubramanian, S; Baller, B; Barnard, A; Barr, G; Barrow, D; et al (August 2025, Physical Review Letters)

   Understanding electron neutrino interactions is crucial for measurements of neutrino oscillations and searches for new physics in neutrino experiments. We present the first measurement of the flux-averaged ${\nu }_e+{\overline{\nu }}_e$ charged-current single charged-pion production cross section on argon using the MicroBooNE detector and data from the NuMI neutrino beam. The total cross section is measured to be $[0.93\pm 0.13(\mathrm{stat})\pm 0.27(\mathrm{syst}\left)\right]\times {10}^{-39}{\mathrm{cm}}^2/\mathrm{nucleon}$ at a mean ${\nu }_e+{\overline{\nu }}_e$ energy of 730 MeV. Differential cross sections are also reported in electron energy, electron and pion angles, and electron-pion opening angle. 

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5. Observation and investigation of the $T_{c\overline{c}1}(4430{)}^{+}$ structure in $B^{+}\to \psi \left(2S\right)K_{\mathrm{S}}^0{\pi }^{+}$ decays

   https://doi.org/10.1103/rcfs-ynh2  

   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 (April 2026, Physical Review D)

   The first four-dimensional amplitude analysis of the $B^{+}\to \psi \left(2S\right)K_{\mathrm{S}}^0{\pi }^{+}$ decay is performed with proton-proton collision data collected by the LHCb experiment at $\sqrt{s}=13\mathrm{TeV}$ , corresponding to an integrated luminosity of $5.4\mathrm{f}{\mathrm{b}}^{-1}$ . The data cannot be fully explained by $B^{+}\to \psi \left(2S\right)K^{*+}$ contributions alone. A significantly better description of the data is obtained by adding a $T_{c\overline{c}}^{+}$ contribution decaying to $\psi \left(2S\right){\pi }^{+}$ . The properties of the $T_{c\overline{c}}^{+}$ structure are consistent with the exotic state $T_{c\overline{c}1}(4430{)}^{+}$ reported in the isospin-related ${\overline{B}}^0\to \psi \left(2S\right)K^{-}{\pi }^{+}$ decay. Effects of a possible $T_{c\overline{c}1}(4430{)}^{+}\to {\overline{D}}_1^{*}(2600{)}^0{D}^{+}$ decay mode on the $T_{c\overline{c}1}(4430{)}^{+}\to \psi (2S){\pi }^{+}$ mass distribution are investigated through a Flatté parametrization, providing constraints on the relative decay strength. A description of the $T_{c\overline{c}1}(4430{)}^{+}$ structure using the triangle singularity mechanism is studied and also found to be consistent with the data. 

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