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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. Measurement of Energy Correlators inside Jets and Determination of the Strong Coupling ${\alpha }_S\left(m_Z\right)$

   https://doi.org/10.1103/PhysRevLett.133.071903  

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

   Energy correlators that describe energy-weighted distances between two or three particles in a hadronic jet are measured using an event sample of $\sqrt{s}=13\mathrm{TeV}$ proton-proton collisions collected by the CMS experiment and corresponding to an integrated luminosity of $36.3{\mathrm{fb}}^{-1}$ . The measured distributions are consistent with the trends in the simulation that reveal two key features of the strong interaction: confinement and asymptotic freedom. By comparing the ratio of the measured three- and two-particle energy correlator distributions with theoretical calculations that resum collinear emissions at approximate next-to-next-to-leading-logarithmic accuracy matched to a next-to-leading-order calculation, the strong coupling is determined at the $Z$ boson mass: ${\alpha }_S\left(m_Z\right)=0.1229_{-0.0050}^{+0.0040}$ , the most precise ${\alpha }_S\left(m_Z\right)$ value obtained using jet substructure observables. © 2024 CERN, for the CMS Collaboration2024CERN 

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