Publications

Order by: publication date number of citations

• Measurements of the Antiquark Flavor Asymmetry in the Proton by the Drell-Yan Experiment SeaQuest

  Kei Nagai

  SciPost Phys. Proc. 8, 119 (2022) · published 13 July 2022 | Toggle abstract · pdf

  The antiquark flavor asymmetry dbar/ubar in the proton gives an insight on the non-perturbative structure of the proton. The SeaQuest experiment measured the Drell–Yan cross section ratio of proton-deuterium to proton-proton to determine the antiquark flavor asymmetry dbar/ubar precisely in the range of 0.13<x<0.45. SeaQuest provides the evidence of dbar/ubar > 1.0 over a wide range of momenta. Some theoretical models reproduce this result.

  1 citation

• Noninvertible symmetry and topological holography for modulated SPT in one dimension

  Jintae Kim, Yizhi You, Jung Hoon Han

  SciPost Phys. 19, 110 (2025) · published 24 October 2025 | Toggle abstract · pdf

  We examine noninvertible symmetry (NIS) in one-dimensional (1D) symmetry-protected topological (SPT) phases protected by dipolar and exponential-charge symmetries, which are two key examples of modulated SPT (MSPT). To set the stage, we first study NIS in the $\mathbb{Z}_N × \mathbb{Z}_N$ cluster model, extending previous work on the $\mathbb{Z}_2 × \mathbb{Z}_2$ case. For each symmetry type (charge, dipole, exponential), we explicitly construct the noninvertible Kramers-Wannier (KW) and Kennedy-Tasaki (KT) transformations, revealing dual models with spontaneous symmetry breaking (SSB). The resulting symmetry group structure of the SSB model is rich enough that it allows the identification of other SSB models with the same symmetry. Using these alternative SSB models and KT duality, we generate novel MSPT phases distinct from those associated with the standard decorated domain wall picture, and confirm their distinctiveness by projective symmetry analyses at their interfaces. Additionally, we establish a topological-holographic correspondence by identifying the 2D bulk theories-two coupled layers of toric codes (charge), anisotropic dipolar toric codes (dipole), and exponentially modulated toric codes (exponential)-whose boundaries host the respective 1D MSPT phases.

  1 citation

• Recent results from the long-baseline (LBL) neutrino oscillation experiments

  Pablo Fernández

  SciPost Phys. Proc. 1, 029 (2019) · published 20 February 2019 | Toggle abstract · pdf

  The results from the current long-baseline neutrino oscillation experiments are reviewed. These experiments are designed to measure the remaining unknown neutrino oscillation parameters via the oscillation of accelerator neutrinos over long distances. The performance of these experiments and their results are described and discussed, giving a precise picture of the current status of the measurements for the neutrino mass ordering, the value of ∆m 232 , the θ 23 and the lepton CP-violating phase, δ CP .

  1 citation

• General simulation method for spontaneous parametric down- and parametric up-conversion experiments

  Felix Riexinger, Mirco Kutas, Björn Haase, Patricia Bickert, Daniel Molter, Michael Bortz, Georg von Freymann

  SciPost Phys. Core 6, 022 (2023) · published 29 March 2023 | Toggle abstract · pdf

  Spontaneous parametric down-conversion (SPDC) sources are an important technology for quantum sensing and imaging. We demonstrate a general simulation method, based on modeling from first principles, reproducing the spectrally and spatially resolved absolute counts of a SPDC experiment. By additionally simulating parametric up- and down-conversion processes with thermal photons as well as effects of the optical system we accomplish good agreement with the experimental results. This method is broadly applicable and allows for the separation of contributing processes, virtual characterization of SPDC sources, and enables the simulation of many quantum based applications.

  1 citation

• Low-energy neutron scattering on light nuclei and $^{19}$B as a $^{17}$B-$n$-$n$ three-body system in the unitary limit

  Jaume Carbonell, Emiko Hiyama, Rimantas Lazauskas, F. Miguel Marqués

  SciPost Phys. Proc. 3, 008 (2020) · published 24 February 2020 | Toggle abstract · pdf

  We consider the evolution of the neutron-nucleus scattering length for the lightest nuclei. We show that, when increasing the number of neutrons in the target nucleus, the strong Pauli repulsion is weakened and the balance with the attractive nucleon-nucleon interaction results into a resonant virtual state in $^{18}$B. We describe $^{19}$B in terms of a $^{17}$B-$n$-$n$ three-body system where the two-body subsystems $^{17}$B-$n$ and $n$-$n$ are unbound (virtual) states close to the unitary limit. The energy of $^{19}$B ground state is well reproduced and two low-lying resonances are predicted. Their eventual link with the Efimov physics is discussed. This model can be extended to describe the recently discovered resonant states in $^{20,21}$B.

  1 citation

• Codebase release 0.2 for JFSD

  Kim William Torre, Raoul D. Schram, Joost de Graaf

  SciPost Phys. Codebases 56-r0.2 (2025) · published 30 June 2025 | Toggle abstract · src

  Stokesian Dynamics (SD) is a powerful computational framework for simulating the motion of particles in a viscous Newtonian fluid under Stokes-flow conditions. Traditional SD implementations can be computationally expensive as they rely on the inversion of large mobility matrices to determine hydrodynamic interactions. Recently, however, the simulation of thermalized systems with large numbers of particles has become feasible [Fiore and Swan, J. Fluid Mech. 878, 544 (2019)]. Their "fast Stokesian dynamics" (FSD) method leverages a saddle-point formulation to ensure overall scaling of the algorithm that is linear in the number of particles $\mathcal{O}(N)$; performance relies on dedicated graphics-processing-unit computing. Here, we present a different route toward implementing FSD, which instead leverages the Just-in-Time (JIT) compilation capabilities of Google JAX. We refer to this implementation as JFSD and perform benchmarks on it to verify that it has the right scaling and is sufficiently fast by the standards of modern computational physics. In addition, we provide a series of physical test cases that help ensure accuracy and robustness, as the code undergoes further development. Thus, JFSD is ready to facilitate the study of hydrodynamic effects in particle suspensions across the domains of soft, active, and granular matter.

  1 citation

• Minimal areas from entangled matrices

  Jackson R. Fliss, Alexander Frenkel, Sean A. Hartnoll, Ronak M. Soni

  SciPost Phys. 18, 171 (2025) · published 2 June 2025 | Toggle abstract · pdf

  We define a relational notion of a subsystem in theories of matrix quantum mechanics and show how the corresponding entanglement entropy can be given as a minimisation, exhibiting many similarities to the Ryu-Takayanagi formula. Our construction brings together the physics of entanglement edge modes, noncommutative geometry and quantum internal reference frames, to define a subsystem whose reduced state is (approximately) an incoherent sum of density matrices, corresponding to distinct spatial subregions. We show that in states where geometry emerges from semiclassical matrices, this sum is dominated by the subregion with minimal boundary area. As in the Ryu-Takayanagi formula, it is the computation of the entanglement that determines the subregion. We find that coarse-graining is essential in our microscopic derivation, in order to control the proliferation of highly curved and disconnected non-geometric subregions in the sum.

  1 citation

• On symmetry-resolved generalized entropies

  Fei Yan, Sara Murciano, Pasquale Calabrese, Robert Konik

  SciPost Phys. 18, 211 (2025) · published 27 June 2025 | Toggle abstract · pdf

  Symmetry-resolved entanglement, capturing the refined structure of quantum entanglement in systems with global symmetries, has attracted a lot of attention recently. In this manuscript, introducing the notion of symmetry-resolved generalized entropies, we aim to develop a computational framework suitable for the study of excited state symmetry-resolved entanglement as well as the dynamical evolution of symmetry-resolved entanglement in symmetry-preserving out-of-equilibrium settings. We illustrate our framework using the example of (1+1)-d free massless compact boson theory, and benchmark our results using lattice computation in the XX chain. As a byproduct, our computational framework also provides access to the probability distribution of the symmetry charge contained within a subsystem and the corresponding full counting statistics.

  1 citation

• Investigations of the few-nucleon systems within the LENPIC project

  Jacek Golak, Evgeny Epelbaum, Alessandro Grassi, Hiroyuki Kamada, Hermann Krebs, Patrick Reinert, Roman Skibiński, Volodymyr Soloviov, Kacper Topolnicki, Vitalii Urbanevych, Yuriy Volkotrub, Henryk Witała

  SciPost Phys. Proc. 3, 002 (2020) · published 24 February 2020 | Toggle abstract · pdf

  Results presented in this contribution are obtained within the Low Energy Nuclear Physics International Collaboration (LENPIC). LENPIC aims to develop chiral nucleon-nucleon and many-nucleon interactions complete through at least the fourth order in the chiral expansion. These interactions will be used together with consistently derived current operators to solve the structure and reactions of light and medium-mass nuclei including electroweak processes. In this contribution the current status of the chiral nuclear forces and current operators will be briefly discussed. A special role played by the calculations of nucleon-deuteron scattering will be explained.

  1 citation

• $μ$-$e$ conversion experiments at J-PARC

  Natsuki Teshima

  SciPost Phys. Proc. 1, 039 (2019) · published 21 February 2019 | Toggle abstract · pdf

  There are two plans of experiments to search for muon to electron ($\mu$-$e$) conversion at J-PARC, which are called DeeMe and COMET. The $\mu$-$e$ conversion is one of the charged lepton flavor violation processes. The processes are forbidden in the Standard Model, but some theories beyond the Standard Model predict relatively large branching ratios at orders of $10^{-12}$ to $10^{-17}$. DeeMe will be conducted with a sensitivity of $1\times10^{-13}$ using a carbon target for 1 year, and COMET will be done with that of $3\times10^{-15}$ in Phase-I. In this article, the current status of these two experiments will be presented.

  1 citation