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1. High-Statistics Measurement of Collins and Sivers Asymmetries for Transversely Polarized Deuterons

   https://doi.org/10.1103/PhysRevLett.133.101903  

   Alexeev, G D; Alexeev, M G; Alice, C; Amoroso, A; Andrieux, V; Anosov, V; Asatryan, S; Augsten, K; Augustyniak, W; Azevedo, C_D R; et al (September 2024, Physical Review Letters)

   New results are presented on a high-statistics measurement of Collins and Sivers asymmetries of charged hadrons produced in deep inelastic scattering of muons on a transversely polarized ${}^6\mathrm{LiD}$target. The data were taken in 2022 with the COMPASS spectrometer using the 160 GeV muon beam at CERN, statistically balancing the existing data on transversely polarized proton targets. The first results from about two-thirds of the new data have total uncertainties smaller by up to a factor of three compared to the previous deuteron measurements. Using all the COMPASS proton and deuteron results, both the transversity and the Sivers distribution functions of the $u$and $d$quark, as well as the tensor charge in the measured $x$range are extracted. In particular, the accuracy of the $d$quark results is significantly improved. Published by the American Physical Society2024 

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2. Dark matter catalyzed baryon destruction

   https://doi.org/10.1103/PhysRevD.111.023005  

   Ema, Yohei; McGehee, Robert; Pospelov, Maxim; Ray, Anupam (January 2025, Physical Review D)

   WIMP-type dark matter may have additional interactions that break baryon number, leading to induced nucleon decays which are subject to direct experimental constraints from proton decay experiments. In this work, we analyze the possibility of continuous baryon destruction, deriving strong limits from the dark matter accumulating inside old neutron stars, as such a process leads to excess heat generation. We construct the simplest particle dark matter model that breaks the baryon and lepton numbers separately but conserves $B-L$. Virtual exchange by DM particles in this model results in dinucleon decay via $nn\to n\overline{\nu }$and $np\to n{e}^{+}$processes. Published by the American Physical Society2025 

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3. Class $\mathcal{S}$ Superconformal Indices from Maximal Supergravity

   https://doi.org/10.1103/PhysRevLett.134.181601  

   Bhattacharya, Ritabrata; Katyal, Abhay; Varela, Oscar (May 2025, Physical Review Letters)

   We present a new gauging of maximal supergravity in five spacetime dimensions with gauge group containing ISO(5), involving the local scaling symmetry of the metric, and admitting a supersymmetric anti–de Sitter vacuum. We show this maximal supergravity to arise by consistent truncation of M theory on the (nonspherical, nonparallelizable) six-dimensional geometry associated to a stack of $N$M5 branes wrapped on a smooth Riemann surface. The existence of this truncation allows us to holographically determine the complete, universal spectrum of light operators of the dual four-dimensional $\mathcal{N}=2$theory of class $\mathcal{S}$. We then compute holographically the superconformal index of the dual field theory at large $N$, finding perfect agreement with previously known field theory results in specific limits. Published by the American Physical Society2025 

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4. 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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5. Measurement of ${\mathrm{\Omega }}_{\mathrm{c}}^0$ baryon production and branching-fraction ratio $\mathrm{BR}({\mathrm{\Omega }}_{\mathrm{c}}^0\to {\mathrm{\Omega }}^{-}{\mathrm{e}}^{+}{\nu }_{\mathrm{e}})/\mathrm{BR}({\mathrm{\Omega }}_{\mathrm{c}}^0\to {\mathrm{\Omega }}^{-}{\pi }^{+})$ in $pp$ collisions at $\sqrt{s}=13\mathrm{TeV}$

   https://doi.org/10.1103/PhysRevD.110.032014  

   Acharya, S; Adamová, D; Agarwal, A; Aglieri_Rinella, G; Aglietta, L; Agnello, M; Agrawal, N; Ahammed, Z; Ahmad, S; Ahn, S U; et al (August 2024, Physical Review D)

   The inclusive production of the charm-strange baryon ${\mathrm{\Omega }}_{\mathrm{c}}^0$is measured for the first time via its semileptonic decay into ${\mathrm{\Omega }}^{-}{\mathrm{e}}^{+}{\nu }_{\mathrm{e}}$at midrapidity ( $\left|y\right|<0.8$) in proton-proton (pp) collisions at the center-of-mass energy $\sqrt{s}=13\mathrm{TeV}$with the ALICE detector at the LHC. The transverse momentum ( $p_{\mathrm{T}}$) differential cross section multiplied by the branching ratio is presented in the interval $2<p_{\mathrm{T}}<12\mathrm{GeV}/c$. The branching-fraction ratio $\mathrm{BR}({\mathrm{\Omega }}_{\mathrm{c}}^0\to {\mathrm{\Omega }}^{-}{\mathrm{e}}^{+}{\nu }_{\mathrm{e}})/\mathrm{BR}({\mathrm{\Omega }}_{\mathrm{c}}^0\to {\mathrm{\Omega }}^{-}{\pi }^{+})$is measured to be $1.12\pm 0.22$(stat) $\pm 0.27$(syst). Comparisons with other experimental measurements, as well as with theoretical calculations, are presented. © 2024 CERN, for the ALICE Collaboration2024CERN 

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