Publications

Order by: publication date number of citations

• 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 $\sim2.2\sigma$.

• Status of the MUonE experiment

  Riccardo N. Pilato

  SciPost Phys. Proc. 16, 034 (2025) · published 15 July 2025 | Toggle abstract · pdf

  The latest measurement of the muon g-2, recently announced at Fermilab, exhibits a 4.2$\sigma$ discrepancy from the Standard Model prediction. The hadronic contribution $a_{\mu}^{HLO}$ represents the main source of uncertainty on the theoretical prediction. The MUonE experiment proposes a novel approach to determine $a_{\mu}^{HLO}$ by measuring the effective electromagnetic coupling in the space-like region, via $\mu - e$ elastic scattering. The measurement is performed by scattering a 160 GeV muon beam, available at CERN, on atomic electrons of a low-Z target. A Test run on a reduced detector is planned in 2022, to validate this proposal. The status of the experiment in view of the Test run is presented.

• Recent ATLAS results on forward physics and diffraction

  Rafał Staszewski

  SciPost Phys. Proc. 15, 011 (2024) · published 2 April 2024 | Toggle abstract · pdf

  The ATLAS detector at the LHC is equipped with dedicated systems designed for the detection of forward protons produced in diffractive and photon-induced processes. These detectors significantly extend the ATLAS physics reach. Recent measurements performed using these forward proton detectors: elastic proton-proton scattering, exclusive charged pion-pair production, and two-photon production of lepton pairs are presented.

• Resummation of the Sivers asymmetry in heavy flavor dijet production at the Electron-Ion Collider

  Zhong-Bo Kang, Jared Reiten, Ding Yu Shao, John Terry

  SciPost Phys. Proc. 8, 175 (2022) · published 14 July 2022 | Toggle abstract · pdf

  We review our transverse momentum dependent factorization and resummation formalism for heavy flavor dijet production at the EIC. In this formalism, we have calculated the heavy flavor mass corrections in the collinear-soft and jet functions, and in the resummed expression for the cross section. By establishing this formalism, we then study the effects of the mass corrections by providing predictions at the EIC for the massive case and for the case where the mass is neglected. We find that the heavy flavor mass effects can give sizable corrections to the predicted asymmetry.

• Fourier-transformed gauge theory models of three-dimensional topological orders with gapped boundaries

  Siyuan Wang, Yanyan Chen, Hongyu Wang, Yuting Hu, Yidun Wan

  SciPost Phys. 19, 018 (2025) · published 17 July 2025 | Toggle abstract · pdf

  In this paper, we apply the method of Fourier transform and basis rewriting developed in [H. Wang et al., J. High Energy Phys. 02, 030 (2020)] for the two-dimensional quantum double model of topological orders to the three-dimensional gauge theory model (with a gauge group $G$) of three-dimensional topological orders. We find that the gapped boundary condition of the gauge theory model is characterized by a Frobenius algebra in the representation category $Rep(G)$ of $G$, which also describes charge splitting and condensation on the boundary. We also show that our Fourier transform maps the three-dimensional gauge theory model with input data $G$ to the Walker-Wang model with input data $Rep(G)$ on a trivalent lattice with dangling edges, after truncating the Hilbert space by projecting all dangling edges to the trivial representation of $G$. This Fourier transform also provides a systematic construction of the gapped boundary theory of the Walker-Wang model. This establishes a correspondence between two types of topological field theories: the extended Dijkgraaf-Witten and extended Crane-Yetter theories.

• Sifting composite from elementary models at FCCee and CePC

  Giacomo Cacciapaglia, Aldo Deandrea, Abhishek M. Iyer, Andres Pinto

  SciPost Phys. 14, 170 (2023) · published 26 June 2023 | Toggle abstract · pdf

  New Physics models with either an elementary or composite origin are often associated with a similar imprint in a direct search at colliders, case in point being the production of a light pseudoscalar in association with a monochromatic photon from the decay of a Z boson at future $e+e-$ colliders. We exploit the correlation between the discovery of a signal in the Z decays and electroweak precision measurements as a tool to distinguish a composite model from an elementary scalar one. Our results offer an appealing and rich physics case for future colliders and demonstrate how a lepton collider at the Z mass can be a discovery machine for new physics in the Higgs sector.

• Gaussian approximation of dynamic cavity equations for linearly-coupled stochastic dynamics

  Mattia Tarabolo, Luca Dall'Asta

  SciPost Phys. 19, 019 (2025) · published 17 July 2025 | Toggle abstract · pdf

  Stochastic dynamics on sparse graphs and disordered systems often lead to complex behaviors characterized by heterogeneity in time and spatial scales, slow relaxation, localization, and aging phenomena. The mathematical tools and approximation techniques required to analyze these complex systems are still under development, posing significant technical challenges and resulting in a reliance on numerical simulations. We introduce a novel computational framework for investigating the dynamics of sparse disordered systems with continuous degrees of freedom. Starting with a graphical model representation of the dynamic partition function for a system of linearly-coupled stochastic differential equations, we use dynamic cavity equations on locally tree-like factor graphs to approximate the stochastic measure. Here, cavity marginals are identified with local functionals of single-site trajectories. Our primary approximation involves a second-order truncation of a small-coupling expansion, leading to a Gaussian form for the cavity marginals. For linear dynamics with additive noise, this method yields a closed set of causal integro-differential equations for cavity versions of one-time and two-time averages. These equations provide an exact dynamical description within the local tree-like approximation, retrieving classical results for the spectral density of sparse random matrices. Global constraints, non-linear forces, and state-dependent noise terms can be addressed using a self-consistent perturbative closure technique. The resulting equations resemble those of dynamical mean-field theory in the mode-coupling approximation used for fully-connected models. However, due to their cavity formulation, the present method can also be applied to ensembles of sparse random graphs and employed as a message-passing algorithm on specific graph instances.

• All order merging of high energy and soft collinear resummation

  Jeppe R. Andersen, Hitham Hassan, Sebastian Jaskiewicz

  SciPost Phys. Proc. 15, 022 (2024) · published 3 April 2024 | Toggle abstract · pdf

  We present a method of merging the exclusive LO-matched high energy resummation of High Energy Jets (HEJ) with the parton shower of PYTHIA which preserves the accuracy of the LO cross sections and the logarithmic accuracy of both resummation schemes across all of phase space. Predictions produced with this merging prescription are presented with comparisons to data from experimental studies and suggestions are made for further observables and experimental cuts which highlight the importance of both high energy and soft-collinear effects.

• ATLAS Results with Beauty Mesons

  Ann-Kathrin Perrevoort

  SciPost Phys. Proc. 8, 099 (2022) · published 13 July 2022 | Toggle abstract · pdf

  A broad range of measurements involving $B$ mesons are performed with the ATLAS experiment at the Large Hadron Collider, of which a selection is discussed in this note. This includes a measurement of the relative $B_c^\pm$ to $B^\pm$ production cross section in $pp$ collisions at a centre-of-mass energy $\sqrt{s}$ of 8 TeV, as well as the latest results on the branching ratios of the rare decays $B^0_s\to\mu^+\mu^-$ and $B^0\to\mu^+\mu^-$ using $pp$ collisions recorded at $\sqrt{s}=$ 7, 8 and 13 TeV. Furthermore, accurate measurements of mixing and CP violation in $B_s^0 \to J/\psi\, \phi$ decays are performed. The latest results on the CP violating phase $\phi_s$ and other parameters describing the decay obtained at $\sqrt{s}=$ 7, 8 and 13 TeV are reported.

• Helix string fragmentation and charged particle correlations with ATLAS

  Šárka Todorova-Nová

  SciPost Phys. Proc. 15, 023 (2024) · published 3 April 2024 | Toggle abstract · pdf

  Correlations between charged particles provide important insight into the hadronization process. The analysis of the momentum difference between charged hadrons in pp, p-lead, and lead-lead collisions at LHC is performed by the ATLAS Collaboration in order to study the dynamics of hadron formation. The spectra of correlated hadron chains are explored and compared to the predictions based on the quantized fragmentation of a three dimensional QCD helix string. This provides an alternative view of the two-particle correlation phenomenon typically attributed to the Bose-Einstein interference.