Publications

Order by: publication date number of citations

• T-violating effect in $\nu_\tau (\bar{\nu}_\tau)-$nucleon quasielastic scattering

  A. Fatima, M. Sajjad Athar and, S. K. Singh

  SciPost Phys. Proc. 16, 026 (2025) · published 15 July 2025 | Toggle abstract · pdf

  The production cross sections and polarization observables of the $\tau$ leptons produced in the $|\Delta S| = 0$ and $1$ induced $\nu_{\tau}(\bar{\nu}_{\tau})-N$ quasielastic scattering have been studied. The effect of T violation, in the case of $\Delta S=0$ and 1 processes, and the SU(3) symmetry breaking effects, in the case of $\Delta S=1$ processes, on the total scattering cross sections as well polarization observables are explored. Experimentally, it would be possible to observe these effects in the forthcoming (anti)neutrino experiments like DUNE, SHiP and DsTau.

• Sparks in the dark

  Olga Sunneborn Gudnadottir, Axel Gallén, Giulia Ripellino, Jochen J. Heinrich, Raazesh Sainudiin, Rebeca Gonzalez Suarez

  SciPost Phys. 18, 080 (2025) · published 4 March 2025 | Toggle abstract · pdf

  This study presents a novel method for the definition of signal regions in searches for new physics at collider experiments. By leveraging multi-dimensional histograms with precise arithmetic and utilizing the SparkDensityTree library, it is possible to identify high-density regions within the available phase space, potentially improving sensitivity to very small signals. Inspired by a search for dark mesons at the ATLAS experiment, CMS open data is used for this proof-of-concept intentionally targeting an already excluded signal. Signal regions are defined based on density estimates of signal and background. These preliminary regions align well with the physical properties of the signal while effectively rejecting background events.

• Classical weight-four L-value ratios as sums of Calabi-Yau invariants

  Philip Candelas, Xenia de la Ossa, Joseph McGovern

  SciPost Phys. 18, 181 (2025) · published 6 June 2025 | Toggle abstract · pdf

  We revisit the series solutions of the attractor equations of 4d $\mathcal{N}=2$ supergravities obtained by Calabi–Yau compactifications previously studied in [P. Candelas et al., J. High Energy Phys. 11, 032 (2021)]. While only convergent for a restricted set of black hole charges, we find that they are summable with Padé resummation providing a suitable method. By specialising these solutions to rank-two attractors, we obtain many conjectural identities of the type discovered in [P. Candelas et al., J. High Energy Phys. 11, 032 (2021)]. These equate ratios of weight-four special L-values with an infinite series whose summands are formed out of genus-0 Gromov–Witten invariants. We also present two new rank-two attractors which belong to moduli spaces each interesting in their own right. Each of these moduli spaces possess two points of maximal unipotent monodromy. One has already been studied by Hosono and Takagi, and we discuss issues stemming from the associated L-function having nonzero rank.

• Clocking mechanism from a minimal spinning particle model

  Tobiasz Pietrzak, Łukasz Bratek

  SciPost Phys. Proc. 14, 042 (2023) · published 24 November 2023 | Toggle abstract · pdf

  The clock hypothesis plays an important role in the theory of relativity. To test this hypothesis, a mechanical model of an ideal clock is needed. Such a model should have the phase of its intrinsic periodic motion increasing linearly with the affine parameter of the clock's center of mass worldline. A class of relativistic rotators introduced by Staruszkiewicz in the context of an ideal clock is studied. A singularity in the inverse Legendre transform leading from the Hamiltonian to the Lagrangian leads to new possible Lagrangians characterized by fixed values of mass and spin. In free motion the rotators exhibit intrinsic motion with the speed of light and fixed frequency.

• The Scattering and Neutrino Detector at the LHC

  Francesco-Luigi Navarria

  SciPost Phys. Proc. 16, 027 (2025) · published 15 July 2025 | Toggle abstract · pdf

  SND@LHC is a compact experiment that will detect high energy neutrinos produced by heavy flavour quarks at the LHC in the pseudo-rapidity region 7.2 $< \eta <$ 8.6. It is an hybrid system, comprising nuclear emulsions and electronic detectors, that allows all three $\nu$ flavours to be distinguished, thus opening an unique opportunity to probe the physics of charm production in the very forward region. The first phase aims at operating the detector throughout LHC Run 3 collecting a total of 150 fb$^{-1}$. The electronic subdetectors were assembled in the summer and recently operated in test beams.

• Towards higher super-$\sigma$-model categories

  Rafał R. Suszek

  SciPost Phys. Proc. 14, 044 (2023) · published 24 November 2023 | Toggle abstract · pdf

  A simplicial framework for the gerbe-theoretic modelling of supercharged-loop dynamics in the presence of worldsheet defects is discussed whose equivariantisation with respect to global supersymmetries of the bulk theory and subsequent orbit decomposition lead to a natural stratification of and cohomological superselection rules for target-space supergeometry, expected to encode essential information on the quantised 2d field theory. A physically relevant example is analysed in considerable detail.

• Real-space spectral simulation of quantum spin models: Application to generalized Kitaev models

  Francisco M. O. Brito, Aires Ferreira

  SciPost Phys. Core 7, 006 (2024) · published 21 February 2024 | Toggle abstract · pdf

  The proliferation of quantum fluctuations and long-range entanglement presents an outstanding challenge for the numerical simulation of interacting spin systems with exotic ground states. Here, we present a toolset of Chebyshev polynomial-based iterative methods that provides a unified framework to study the thermodynamical properties, critical behavior and dynamics of frustrated quantum spin models with controlled accuracy. Similar to previous applications of the Chebyshev spectral methods to condensed matter systems, the algorithmic complexity scales linearly with the Hilbert space dimension and the Chebyshev truncation order. Using this approach, we study two paradigmatic quantum spin models on the honeycomb lattice: the Kitaev-Heisenberg (K-H) and the Kitaev-Ising (K-I) models. We start by applying the Chebyshev toolset to compute nearest-neighbor spin correlations, specific heat and entropy of the K-H model on a 24-spin cluster. Our results are benchmarked against exact diagonalization and a popular iterative method based on thermal pure quantum states. The transitions between a variety of magnetic phases, namely ferromagnetic, Néel, zigzag and stripy antiferromagnetic and quantum spin liquid phases are obtained accurately and efficiently. We also determine the temperature dependence of the spin correlations, over more than three decades in temperature, by means of a finite temperature Chebyshev polynomial method introduced here. Finally, we report novel dynamical signatures of the quantum phase transitions in the K-I model. Our findings suggest that the efficiency, versatility and low-temperature stability of the Chebyshev framework developed here could pave the way for previously unattainable studies of quantum spin models in two dimensions.

• New $\tau$-based evaluation of the hadronic vacuum polarization contribution to the muon anomalous magnetic moment

  Jesús Alejandro Miranda Hernández, Pablo Roig Garcés

  SciPost Phys. Proc. 16, 032 (2025) · published 15 July 2025 | Toggle abstract · pdf

  We revisit the radiative corrections to the $\tau^-\to\pi^-\pi^0\nu_\tau(\gamma)$ decays using Resonance Chiral Theory for the structure-dependent part. This channel is the most important one to understand the hadronic vacuum polarization piece of the muon g-2, which dominates the uncertainty of its data-driven prediction in the Standard Model. Using our results, the discrepancy between theory and experiment for this observable is reduced to $\sim2.2\sigma$.

• Construction of matryoshka nested indecomposable N-replications of Kac-modules of quasi-reductive Lie superalgebras, including the sl(m/n) and osp(2/2n) series

  Jean Thierry-Mieg, Peter D. Jarvis, Jerome Germoni, Maria Gorelik

  SciPost Phys. Proc. 14, 045 (2023) · published 24 November 2023 | Toggle abstract · pdf

  We construct a new class of finite dimensional indecomposable representations of simple superalgebras which may explain, in a natural way, the existence of the heavier elementary particles. In type I Lie superalgebras sl(m/n) and osp(2/2n), one of the Dynkin weights labeling the finite dimensional irreducible representations is continuous. Taking the derivative, we show how to construct indecomposable representations recursively embedding N copies of the original irreducible representation, coupled by generalized Cabibbo angles, as observed among the three generations of leptons and quarks of the standard model. The construction is then generalized in the appendix to quasi-reductive Lie superalgebras.

• The parastatistics of braided Majorana fermions

  Francesco Toppan

  SciPost Phys. Proc. 14, 046 (2023) · published 24 November 2023 | Toggle abstract · pdf

  This paper presents the parastatistics of braided Majorana fermions obtained in the framework of a graded Hopf algebra endowed with a braided tensor product. The braiding property is encoded in a t-dependent 4×4 braiding matrix $B_t$ related to the Alexander-Conway polynomial. The nonvanishing complex parameter t defines the braided parastatistics. At t=1 ordinary fermions are recovered. The values of t at roots of unity are organized into levels which specify the maximal number of braided Majorana fermions in a multiparticle sector. Generic values of t and the t=-1 root of unity mimick the behaviour of ordinary bosons.