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1. Stokes flows in three-dimensional fluids with odd and parity-violating viscosities

   https://doi.org/10.1017/jfm.2021.1079  

   Khain, Tali ; Scheibner, Colin ; Fruchart, Michel ; Vitelli, Vincenzo ( March 2022 , Journal of Fluid Mechanics)

   The Stokes equation describes the motion of fluids when inertial forces are negligible compared with viscous forces. In this article, we explore the consequence of parity-violating and non-dissipative (i.e. odd) viscosities on Stokes flows in three dimensions. Parity-violating viscosities are coefficients of the viscosity tensor that are not invariant under mirror reflections of space, while odd viscosities are those which do not contribute to dissipation of mechanical energy. These viscosities can occur in systems ranging from synthetic and biological active fluids to magnetized and rotating fluids. We first systematically enumerate all possible parity-violating viscosities compatible with cylindrical symmetry, highlighting their connection to potential microscopic realizations. Then, using a combination of analytical and numerical methods, we analyse the effects of parity-violating viscosities on the Stokeslet solution, on the flow past a sphere or a bubble and on many-particle sedimentation. In all the cases that we analyse, parity-violating viscosities give rise to an azimuthal flow even when the driving force is parallel to the axis of cylindrical symmetry. For a few sedimenting particles, the azimuthal flow bends the trajectories compared with a traditional Stokes flow. For a cloud of particles, the azimuthal flow impedes the transformation of the spherical cloud into a torus and the subsequent breakup into smaller parts that would otherwise occur. The presence of azimuthal flows in cylindrically symmetric systems (sphere, bubble, cloud of particles) can serve as a probe for parity-violating viscosities in experimental systems. 

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2. Search for R-parity-violating supersymmetry in a final state containing leptons and many jets with the ATLAS experiment using $$\sqrt{s} = 13\hbox { TeV}$$ proton–proton collision data

   https://doi.org/10.1140/epjc/s10052-021-09761-x  

   Aad, G. ; Abbott, B. ; Abbott, D. C. ; Abud, A. Abed ; Abeling, K. ; Abhayasinghe, D. K. ; Abidi, S. H. ; Abramowicz, H. ; Abreu, H. ; Abulaiti, Y. ; et al ( November 2021 , The European Physical Journal C)

   Abstract A search for R-parity-violating supersymmetry in final states characterized by high jet multiplicity, at least one isolated light lepton and either zero or at least three b -tagged jets is presented. The search uses $${139}\,{\text {fb}^{-1}}$$ 139 fb - 1 of $$\sqrt{s} = {13}\hbox { TeV}$$ s = 13 TeV proton–proton collision data collected by the ATLAS experiment during Run 2 of the Large Hadron Collider. The results are interpreted in the context of R-parity-violating supersymmetry models that feature gluino production, top-squark production, or electroweakino production. The dominant sources of background are estimated using a data-driven model, based on observables at medium jet multiplicity, to predict the b -tagged jet multiplicity distribution at the higher jet multiplicities used in the search. Machine-learning techniques are used to reach sensitivity to electroweakino production, extending the data-driven background estimation to the shape of the machine-learning discriminant. No significant excess over the Standard Model expectation is observed and exclusion limits at the 95% confidence level are extracted, reaching as high as 2.4 TeV in gluino mass, 1.35 TeV in top-squark mass, and 320 (365) GeV in higgsino (wino) mass. 

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3. Ultrasensitive, Parity–Time-Symmetric Wireless Reactive and Resistive Sensors

   https://doi.org/10.1109/JSEN.2018.2870322  

   Sakhdari, Maryam ; Hajizadegan, Mehdi ; Li, Yue ; Cheng, Mark Ming-Cheng ; Hung, Jonathan C. ; Chen, Pai-Yen ( December 2018 , IEEE Sensors Journal)
4. First Precision Measurement of the Parity Violating Asymmetry in Cold Neutron Capture on He3

   https://doi.org/10.1103/PhysRevLett.125.131803  

   Gericke, M. T. ; Baeßler, S. ; Barrón-Palos, L. ; Birge, N. ; Bowman, J. D. ; Calarco, J. ; Cianciolo, V. ; Coppola, C. E. ; Crawford, C. B. ; Fomin, N. ; et al ( September 2020 , Physical Review Letters)

   null (Ed.)
5. Constraining R -parity-violating couplings in τ -processes at the LHC and in electroweak precision measurements

   https://doi.org/10.1103/PhysRevD.100.093005  

   Bansal, Saurabh ; Delgado, Antonio ; Kolda, Christopher ; Quiros, Mariano ( November 2019 , Physical Review D)