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1. Search for a light sterile neutrino with 7.5 years of IceCube DeepCore data

   https://doi.org/10.1103/PhysRevD.110.072007  

   Abbasi, R; Ackermann, M; Adams, J; Agarwalla, S K; Aguilar, J A; Ahlers, M; Alameddine, J M; Amin, N M; Andeen, K; Argüelles, C; et al (October 2024, Physical Review D)

   We present a search for an eV-scale sterile neutrino using 7.5 years of data from the IceCube DeepCore detector. The analysis uses a sample of 21,914 events with energies between 5 and 150 GeV to search for sterile neutrinos through atmospheric muon neutrino disappearance. Improvements in event selection and treatment of systematic uncertainties provide greater statistical power compared to previous DeepCore sterile neutrino searches. Our results are compatible with the absence of mixing between active and sterile neutrino states, and we place constraints on the mixing matrix elements $|U_{\mu 4}{|}^2<0.0534$ and $|U_{\tau 4}{|}^2<0.0574$ at 90% CL under the assumption that $\mathrm{\Delta }{m}_{41}^2\ge 1{\mathrm{eV}}^2$ . These null results add to the growing tension between anomalous appearance results and constraints from disappearance searches in the $3+1$ sterile neutrino landscape. Published by the American Physical Society2024 

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2. Search for an eV-Scale Sterile Neutrino Using Improved High-Energy ${\nu }_{\mu }$ Event Reconstruction in IceCube

   https://doi.org/10.1103/PhysRevLett.133.201804  

   Abbasi, R; Ackermann, M; Adams, J; Agarwalla, S K; Aguilar, J A; Ahlers, M; Alameddine, J M; Amin, N M; Andeen, K; Argüelles, C; et al (November 2024, Physical Review Letters)

   This Letter presents the result of a $3+1$ sterile neutrino search using 10.7 yr of IceCube data. We analyze atmospheric muon neutrinos that traverse the Earth with energies ranging from 0.5 to 100 TeV, incorporating significant improvements in modeling neutrino flux and detector response compared to earlier studies. Notably, for the first time, we categorize data into starting and throughgoing events, distinguishing neutrino interactions with vertices inside or outside the instrumented volume, to improve energy resolution. The best-fit point for a $3+1$ model is found to be at ${\sin }^2\left(2{\theta }_{24}\right)=0.16$ and $\mathrm{\Delta }{m}_{41}^2=3.5{\mathrm{eV}}^2$ , which agrees with previous iterations of this Letter. The result is consistent with the null hypothesis of no sterile neutrinos with a $p$ value of 3.1%. Published by the American Physical Society2024 

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3. First Search for $B\to X_s\nu \overline{\nu }$ Decays

   https://doi.org/10.1103/kf73-hw61  

   Abumusabh, M; Adachi, I; Adamczyk, K; Aggarwal, L; Ahmed, H; Ahn, Y; Aihara, H; Akopov, N; Alghamdi, S; Alhakami, M; et al (June 2026, Physical Review Letters)

   We report the first search for the flavor-changing neutral-current decays $B\to X_s\nu \overline{\nu }$ , where $X_s$ is a hadronic system with strangeness equal to 1, in data collected with the Belle II detector at the SuperKEKB asymmetric-energy $e^{+}{e}^{-}$ collider. The data sample corresponds to an integrated luminosity of $365{\mathrm{fb}}^{-1}$ collected at the $\mathrm{\Upsilon }\left(4S\right)$ resonance and $43{\mathrm{fb}}^{-1}$ collected at a center-of-mass energy 60 MeV below resonance for estimation of $e^{+}{e}^{-}\to q\overline{q}$ continuum background. One of the $B$ mesons from the $\mathrm{\Upsilon }\left(4S\right)\to B\overline{B}$ decay is fully reconstructed in a hadronic decay mode. The $B\to X_s\nu \overline{\nu }$ decay is reconstructed with a sum-of-exclusives approach that uses 30 $X_s$ decay modes. This approach provides high sensitivity to the inclusive decay, despite the presence of two undetected neutrinos. The search is performed in three regions of the $X_s$ mass, $M_{X_s}^{\mathrm{true}}$ , chosen to separate contributions from $K$ , $K^{*}\left(892\right)$ , and heavier strange final states. We do not observe a significant signal and set upper limits at 90% confidence level on the partial branching fractions for the regions $0.0<M_{X_s}^{\mathrm{true}}<0.6\mathrm{GeV}/c^2$ , $0.6<M_{X_s}^{\mathrm{true}}<1.0\mathrm{GeV}/c^2$ , and $1.0\mathrm{GeV}/c^2<M_{X_s}^{\mathrm{true}}$ of $2.2\times {10}^{-5}$ , $9.3\times {10}^{-5}$ , and $30.9\times {10}^{-5}$ , respectively. Combining the three mass regions, we obtain the upper limit on the branching fraction, $B(B\to X_s\nu \overline{\nu })<3.3\times {10}^{-4}$ . 

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4. Methods and stability tests associated with the sterile neutrino search using improved high-energy ${\nu }_{\mu }$ event reconstruction in IceCube

   https://doi.org/10.1103/PhysRevD.110.092009  

   Abbasi, R; Ackermann, M; Adams, J; Agarwalla, S K; Aguilar, J A; Ahlers, M; Alameddine, J M; Amin, N M; Andeen, K; Argüelles, C; et al (November 2024, Physical Review D)

   We provide supporting details for the search for a $3+1$ sterile neutrino using data collected over 10.7 years at the IceCube Neutrino Observatory. The analysis uses atmospheric muon-flavored neutrinos from 0.5 to 100 TeV that traverse Earth to reach the IceCube detector and finds a best-fit point at ${\sin }^2\left(2{\theta }_{24}\right)=0.16$ and $\mathrm{\Delta }{m}_{41}^2=3.5{\mathrm{eV}}^2$ with a goodness-of-fit p value of 12% and consistency with the null hypothesis of no oscillations to sterile neutrinos with a p value of 3.1%. Several improvements were made over past analyses, which are reviewed in this article, including upgrades to the reconstruction and the study of sources of systematic uncertainty. We provide details of the fit quality and discuss stability tests that split the data for separate samples, comparing results. We find that the fits are consistent between split datasets. Published by the American Physical Society2024 

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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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