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1. Massless fermions in uniform flux background on $T^2\times R$ : Vacuum quantum numbers from single-particle filled modes using lattice regulator

   https://doi.org/10.1103/PhysRevD.111.014502  

   Karthik, Nikhil; Narayanan, Rajamani; Romero, Ray (January 2025, Physical Review D)

   The quantum numbers of monopoles in $R^3$in the presence of massless fermions have been analyzed using a uniform flux background in $S^2\times R$coupled to fermions. An analogous study in $T^2\times R$is performed by studying the discrete symmetries of the Dirac Hamiltonian in the presence of a static uniform field on $T^2$with a total flux of $Q$in the continuum. The degenerate ground states are classified based on their transformation properties under $\frac{\pi }{2}$rotations of $T^2$that leave the background field invariant. We find that the lattice analysis with overlap fermions exactly reproduces the transformation properties of the single-particle zero modes in the continuum. Whereas the transformation properties of the single-particle negative energy states can be studied in the continuum and the lattice, we are also able to study the transformation properties and the particle number (charge) of the many-body ground state on a finite lattice, and we show that the contributions from the fully filled single-particle states cannot be ignored. Published by the American Physical Society2025 

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2. $K^{*}{\left(892\right)}^0$ and $\varphi \left(1020\right)$ production at midrapidity in $pp$ collisions at $\sqrt{s}=8$ TeV

   https://doi.org/10.1103/PhysRevC.102.024912  

   Acharya, S.; Adamová, D.; Adhya, S. P.; Adler, A.; Adolfsson, J.; Aggarwal, M. M.; Aglieri Rinella, G.; Agnello, M.; Agrawal, N.; Ahammed, Z.; et al (August 2020, Physical Review C)

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3. Investigating strangeness enhancement in jet and medium via $\varphi \left(1020\right)$ production in $p$ -Pb collisions at $\sqrt{s_{NN}}=5.02\mathrm{TeV}$

   https://doi.org/10.1103/PhysRevC.110.064912  

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

   This work aims to differentiate strangeness produced from hard processes (jetlike) and softer processes (underlying event) by measuring the angular correlation between a high-momentum trigger hadron ( $h$) acting as a jet proxy and a produced strange hadron [ $\varphi \left(1020\right)$meson]. Measuring $h\text{−}\varphi$correlations at midrapidity in $p$-Pb collisions at $\sqrt{s_{NN}}=5.02\mathrm{TeV}$as a function of event multiplicity provides insight into the microscopic origin of strangeness enhancement in small collision systems. The jetlike and the underlying-event-like strangeness production are investigated as a function of event multiplicity. They are also compared between a lower and higher momentum region. The evolutions of the per-trigger yields within the near-side (aligned with the trigger hadron) and away-side (in the opposite direction of the trigger hadron) jets are studied separately, allowing for the characterization of two distinct jetlike production regimes. Furthermore, the $h\text{−}\varphi$correlations within the underlying event give access to a production regime dominated by soft production processes, which can be compared directly to the in-jet production. Comparisons between $h\text{−}\varphi$and dihadron correlations show that the observed strangeness enhancement is largely driven by the underlying event, where the $\varphi /h$ratio is significantly larger than within the jet regions. As multiplicity increases, the fraction of the total $\varphi \left(1020\right)$yield coming from jets decreases compared to the underlying event production, leading to high-multiplicity events being dominated by the increased strangeness production from the underlying event. ©2024 CERN, for the ALICE Collaboration2024CERN 

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4. $K^{*}{\left(892\right)}^0$ and $\varphi \left(1020\right)$ production in $p\text{−}\mathrm{Pb}$ collisions at $\sqrt{s_{NN}}=8.16 \mathrm{TeV}$

   https://doi.org/10.1103/PhysRevC.107.055201  

   Acharya, S.; Adamová, D.; Adler, A.; Adolfsson, J.; Aglieri Rinella, G.; Agnello, M.; Agrawal, N.; Ahammed, Z.; Ahmad, S.; Ahn, S. U.; et al (May 2023, Physical Review C)
5. Multiband mean-field theory of the $d+ig$ superconductivity scenario in ${\mathrm{Sr}}_2{\mathrm{RuO}}_4$

   https://doi.org/10.1103/PhysRevB.108.014502  

   Yuan, Andrew C; Berg, Erez; Kivelson, Steven A (July 2023, Physical Review B)

   Many seemingly contradictory experimental findings concerning the superconducting state in Sr2RuO4 can be accounted for on the basis of a conjectured accidental degeneracy between two patterns of pairing that are unrelated to each other under the (D4h) symmetry of the crystal: a dx2-y2-wave (B1g) and a gxy(x2-y2)-wave (A2g) superconducting state. In this paper, we propose a generic multiband model in which the g-wave pairing involving the xz and yz orbitals arises from second-nearest-neighbor BCS channel effective interactions. Even if timereversal symmetry is broken in a d + ig state, such a superconductor remains gapless with a Bogoliubov Fermi surface that approximates a (vertical) line node. The model gives rise to a strain-dependent splitting between the critical temperature Tc and the time-reversal symmetry-breaking temperature TTRSB that is qualitatively similar to some of the experimental observations in Sr2RuO4. 

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