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1. A QCD $R$ -axion

   https://doi.org/10.1103/PhysRevD.111.015048  

   Unwin, James; Yildirim, Tom (January 2025, Physical Review D)

   $R$-parity can be extended to a continuous global $\mathrm{U}(1{)}_R$symmetry. We investigate whether an anomalous $\mathrm{U}(1{)}_R$can be identified as the Peccei-Quinn symmetry suitable for solving the strong $CP$problem within supersymmetric extensions of the Standard Model. In this case, $\mathrm{U}(1{)}_R$is broken at some intermediate scale and the quantum chromodynamics axion is the $R$-axion. Moreover, the $R$-symmetry can potentially be gauged via the Green-Schwarz mechanism within completions to supergravity, in order to evade the axion quality problem. Obstacles to realizing this scenario are highlighted and phenomenologically viable approaches are identified. Published by the American Physical Society2025 

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2. One-jettiness DIS event shape at ${\mathrm{N}}^3\mathrm{LL}+\mathcal{O}\left({\alpha }_s^2\right)$

   https://doi.org/10.1103/PhysRevD.110.014045  

   Cao, Haotian; Kang, Zhong-Bo; Liu, Xiaohui; Mantry, Sonny (July 2024, Physical Review D)

   We present results for the ${\tau }_1$and ${\tau }_{1a}$1-jettiness global event shape distributions, for deep inelastic scattering (DIS), at the ${\mathrm{N}}^3\mathrm{LL}+\mathcal{O}\left({\alpha }_s^2\right)$level of accuracy. These event-shape distributions quantify and characterize the pattern of final state radiation in electron-nucleus collisions. They can be used as a probe of nuclear structure functions, as nuclear medium effects in jet production, and for a precision extraction of the QCD strong coupling. The results presented here, along with the corresponding numerical codes, can be used for analyses with HERA data, in Electron-Ion Collider (EIC) simulation studies, and for eventual comparison with real EIC data. Published by the American Physical Society2024 

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3. Lam-Tung relation breaking in $Z$ boson production as a probe of standard model effective field theory effects

   https://doi.org/10.1103/PhysRevD.111.073007  

   Li, Xu; Yan, Bin; Yuan, C-P (April 2025, Physical Review D)

   The violation of the Lam-Tung relation in the high- $p_T^{\ell \ell }$region of the Drell-Yan process at the LHC presents a longstanding discrepancy with the standard model prediction at $\mathcal{O}\left({\alpha }_s^3\right)$accuracy. In this paper, we employed a model-independent analysis to investigate this phenomenon within the framework of the standard model effective field theory (SMEFT). Our findings revealed that the leading contributions from SMEFT to this violation appear at the $1/{\mathrm{\Lambda }}^4$order with $\mathcal{O}\left({\alpha }_s\right)$accuracy in quantum chromodynamics (QCD) interaction. Notably, we demonstrated that the quadratic effect of dimension-6 dipole operators, associated with the $Z$boson, dominates the breaking effects induced by various dimension-6 and dimension-8 operators. This provides a possible explanation for the observed discrepancy with the Standard Model predictions at the LHC. Furthermore, the breaking effects could also serve as a powerful tool for constraining $Z$-boson dipole interactions, highlighting their importance among potential sources of new physics in the Drell-Yan process. Published by the American Physical Society2025 

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4. Search for two-body $B$ meson decays to ${\mathrm{\Lambda }}^0$ and ${\mathrm{\Omega }}_c^{(*)0}$

   https://doi.org/10.1103/PhysRevD.110.L031102  

   Savinov, V; Adachi, I; Ahn, J K; Aihara, H; Asner, D M; Atmacan, H; Ayad, R; Banerjee, Sw; Bennett, J; Bessner, M; et al (August 2024, Physical Review D)

   We report the results of the first search for Standard Model and baryon-number-violating two-body decays of the neutral $B$mesons to ${\mathrm{\Lambda }}^0$and ${\mathrm{\Omega }}_c^{(*)0}$using $711{\mathrm{fb}}^{-1}$of data collected at the $\mathrm{\Upsilon }\left(4S\right)$resonance with the Belle detector at the KEKB asymmetric-energy $e^{+}{e}^{-}$collider. We observe no evidence of signal from any such decays and set 95% confidence-level upper limits on the products of $B^0$and ${\overline{B}}^0$branching fractions for these two-body decays with $\mathcal{B}({\mathrm{\Omega }}_c^0\to {\pi }^{+}{\mathrm{\Omega }}^{-})$in the range between $9.5\times {10}^{-8}$and $31.2\times {10}^{-8}$. Published by the American Physical Society2024 

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5. Rationality in four dimensions

   https://doi.org/10.1103/PhysRevD.109.105018  

   Rastelli, Leonardo; Rayhaun, Brandon C (May 2024, Physical Review D)

   By leveraging the physics of the Higgs branch, we argue that the conformal central charges $a$and $c$of an arbitrary 4D $\mathcal{N}=2$superconformal field theory (SCFT) are rational numbers. Our proof of the rationality of $c$is conditioned on a well-supported conjecture about how the Higgs branch of an SCFT is encoded in its protected chiral algebra. To establish the rationality of $a$, we further rely on a widely believed technical assumption on the high-temperature limit of the superconformal index. Published by the American Physical Society2024 

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