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1. Search for pair production of scalar and vector leptoquarks decaying to muons and bottom quarks in proton-proton collisions at $\sqrt{s}=13\mathrm{TeV}$

   https://doi.org/10.1103/PhysRevD.109.112003  

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

   A search for pair production of scalar and vector leptoquarks (LQs) each decaying to a muon and a bottom quark is performed using proton-proton collision data collected at $\sqrt{s}=13\mathrm{TeV}$with the CMS detector at the CERN LHC, corresponding to an integrated luminosity of $138{\mathrm{fb}}^{-1}$. No excess above standard model expectation is observed. Scalar (vector) LQs with masses less than 1810 (2120) GeV are excluded at 95% confidence level, assuming a 100% branching fraction of the LQ decaying to a muon and a bottom quark. These limits represent the most stringent to date. © 2024 CERN, for the CMS Collaboration2024CERN 

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2. First Search for Ultralight Dark Matter Using a Magnetically Levitated Particle

   https://doi.org/10.1103/PhysRevLett.134.251001  

   Amaral, Dorian_W P; Uitenbroek, Dennis G; Oosterkamp, Tjerk H; Tunnell, Christopher D (June 2025, Physical Review Letters)

   We perform the first search for ultralight dark matter using a magnetically levitated particle. A submillimeter permanent magnet is levitated in a superconducting trap with a measured force sensitivity of $0.2\mathrm{fN}/\sqrt{\mathrm{Hz}}$. We find no evidence of a signal and derive limits on dark matter coupled to the difference between baryon and lepton number, $B-L$, in the mass range $(1.10360-1.10485)\times {10}^{-13}\mathrm{eV}/c^2$. Our most stringent limit on the coupling strength is $g_{B-L}\lesssim 2.98\times {10}^{-21}$. We propose the POLONAISE (Probing Oscillations using Levitated Objects for Novel Accelerometry In Searches of Exotic physics) experiment, which features short-, medium-, and long-term upgrades that will give us leading sensitivity in a wide mass range, demonstrating the promise of this novel quantum sensing technology in the hunt for dark matter. Published by the American Physical Society2025 

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3. Search for New Resonances Decaying to Pairs of Merged Diphotons in Proton-Proton Collisions at $\sqrt{s}=13\mathrm{TeV}$

   https://doi.org/10.1103/PhysRevLett.134.041801  

   Hayrapetyan, A; Tumasyan, A; Adam, W; Andrejkovic, J W; Bergauer, T; Chatterjee, S; Damanakis, K; Dragicevic, M; Hussain, P S; Jeitler, M; et al (January 2025, Physical Review Letters)

   A search is presented for an extended Higgs sector with two new particles, $X$and $\varphi$, in the process $X\to \varphi \varphi \to \left(\gamma \gamma \right)\left(\gamma \gamma \right)$. Novel neural networks classify events with diphotons that are merged and determine the diphoton masses. The search uses LHC proton-proton collision data at $\sqrt{s}=13\mathrm{TeV}$collected with the CMS detector, corresponding to an integrated luminosity of $138{\mathrm{fb}}^{-1}$. No evidence of such resonances is seen. Upper limits are set on the production cross section for $m_X$between 300 and 3000 GeV and $m_{\varphi }/m_X$between 0.5% and 2.5%, representing the most sensitive search in this channel. © 2025 CERN, for the CMS Collaboration2025CERN 

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4. Searches for Pair-Produced Multijet Resonances Using Data Scouting in Proton-Proton Collisions at $\sqrt{s}=13\mathrm{TeV}$

   https://doi.org/10.1103/PhysRevLett.133.201803  

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

   Searches for pair-produced multijet signatures using data corresponding to an integrated luminosity of $128{\mathrm{fb}}^{-1}$of proton-proton collisions at $\sqrt{s}=13\mathrm{TeV}$are presented. A data scouting technique is employed to record events with low jet scalar transverse momentum sum values. The electroweak production of particles predicted in $R$-parity violating supersymmetric models is probed for the first time with fully hadronic final states. This is the first search for prompt hadronically decaying mass-degenerate higgsinos, and extends current exclusions on $R$-parity violating top squarks and gluinos. © 2024 CERN, for the CMS Collaboration2024CERN 

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5. Search for a ${\mu }^{+}{\mu }^{-}$ resonance in four-muon final states at Belle II

   https://doi.org/10.1103/PhysRevD.109.112015  

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

   We report on a search for a resonance $X$decaying to a pair of muons in $e^{+}{e}^{-}\to {\mu }^{+}{\mu }^{-}X$events in the $0.212–9.000\mathrm{GeV}/c^2$mass range, using $178{\mathrm{fb}}^{-1}$of data collected by the Belle II experiment at the SuperKEKB collider at a center of mass energy of 10.58 GeV. The analysis probes two different models of $X$beyond the standard model: a $Z^{\prime }$vector boson in the $L_{\mu }-L_{\tau }$model and a muonphilic scalar. We observe no evidence for a signal and set exclusion limits at the 90% confidence level on the products of cross section and branching fraction for these processes, ranging from 0.046 fb to 0.97 fb for the $L_{\mu }-L_{\tau }$model and from 0.055 fb to 1.3 fb for the muonphilic scalar model. For masses below $6\mathrm{GeV}/c^2$, the corresponding constraints on the couplings of these processes to the standard model range from 0.0008 to 0.039 for the $L_{\mu }-L_{\tau }$model and from 0.0018 to 0.040 for the muonphilic scalar model. These are the first constraints on the muonphilic scalar from a dedicated search. Published by the American Physical Society2024 

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