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1. Enantioselective One-Photon Excitation of Formic Acid

   https://doi.org/10.1103/PhysRevLett.133.093002  

   Tsitsonis, D; Trinter, F; Williams, J B; Fehre, K; Demekhin, Ph V; Jahnke, T; Dörner, R; Schöffler, M S (August 2024, Physical Review Letters)

   We use one-photon excitation to promote $K$-shell electrons of formic acid (which has a planar equilibrium structure) to an antibonding ${\pi }^{*}$orbital. The excited molecule is known to have a (chiral) pyramidal equilibrium structure. In our experiment, we determine the handedness of the excited molecule by imaging the momenta of charged fragments, which occur after its Coulomb explosion triggered by Auger-Meitner decay cascades succeeding the excitation. We find that the handedness of the excited molecule depends on its spatial orientation with respect to the propagation (or polarization) direction of the exciting photon. The effect is largely independent of the exact polarization properties of the light driving the $1s\to {\pi }^{*}$excitation. Published by the American Physical Society2024 

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2. Measurement of the branching fraction and $CP$ -violating asymmetry of the decay $B^0\to {\pi }^0{\pi }^0$ using 387 million $\mathrm{\Upsilon }\left(4S\right)$ decays in Belle II data

   https://doi.org/10.1103/PhysRevD.111.L071102  

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

   We measure the branching fraction and $CP$-violating flavor-dependent rate asymmetry of $B^0\to {\pi }^0{\pi }^0$decays reconstructed using the Belle II detector in an electron-positron collision sample containing $387\times {10}^6\mathrm{\Upsilon }\left(4S\right)$mesons. Using an optimized event selection, we find $125\pm 20$signal decays in a fit to background-discriminating and flavor-sensitive distributions. The resulting branching fraction is $(1.25\pm 0.23)\times {10}^{-6}$and the $CP$-violating asymmetry is $0.03\pm 0.30$. Published by the American Physical Society2025 

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3. Measurements of the Branching Fraction, Polarization, and $CP$ Asymmetry for the Decay $B^0\to \omega \omega$

   https://doi.org/10.1103/PhysRevLett.133.081801  

   Guan, Y; Schwartz, A J; Kinoshita, K; Adachi, I; Aihara, H; Al_Said, S; Asner, D M; Atmacan, H; Ayad, R; Bahinipati, S; et al (August 2024, Physical Review Letters)

   We present a comprehensive study of $B^0\to \omega \omega$decays using $772\times {10}^{6}B\overline{B}$pairs collected with the Belle detector at the KEKB $e^{+}{e}^{-}$collider. This process is a suppressed charmless decay into two vector mesons and can exhibit interesting polarization and $CP$violation. The decay is observed for the first time with a significance of 7.9 standard deviations. We measure a branching fraction $\mathcal{B}=(1.53\pm 0.29\pm 0.17)\times {10}^{-6}$, a fraction of longitudinal polarization $f_L=0.87\pm 0.13\pm 0.13$, and a time-integrated $CP$asymmetry $A_{CP}=-0.44\pm 0.43\pm 0.11$, where the first uncertainties listed are statistical and the second are systematic. This is the first observation of $B^0\to \omega \omega$and the first measurements of $f_L$and $A_{CP}$for this decay. Published by the American Physical Society2024 

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4. Search for heavy neutral resonances decaying to tau lepton pairs in proton-proton collisions at $\sqrt{s}=13\mathrm{TeV}$

   https://doi.org/10.1103/PhysRevD.111.112004  

   Hayrapetyan, A; Tumasyan, A; Adam, W; Andrejkovic, J W; Benato, L; Bergauer, T; Chatterjee, S; Damanakis, K; Dragicevic, M; Hussain, P S; et al (June 2025, Physical Review D)

   PRD (Ed.)

   A search for heavy neutral gauge bosons ( $Z^{\prime }$) decaying into a pair of tau leptons is performed in proton-proton collisions at $\sqrt{s}=13\mathrm{TeV}$at the CERN LHC. The data were collected with the CMS detector and correspond to an integrated luminosity of $138{\mathrm{fb}}^{-1}$. The observations are found to be in agreement with the expectation from standard model processes. Limits at 95% confidence level are set on the product of the $Z^{\prime }$production cross section and its branching fraction to tau lepton pairs for a range of $Z^{\prime }$boson masses. For a narrow resonance in the sequential standard model scenario, a $Z^{\prime }$boson with a mass below 3.5 TeV is excluded. This is the most stringent limit to date from this type of search. © 2025 CERN, for the CMS Collaboration2025CERN 

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5. 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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