Publications

Order by: publication date number of citations

$e^+e^-$ hadronic cross-sections with SND detector at VEPP 2000

T. V. Dimova, M. N. Achasov, A. Yu. Barnyakov, K. I. Beloborodov, A. V. Berdyugin, A. G. Bogdanchikov, A. A. Botov, V. P. Druzhinin, L. V. Kardapoltsev, A. G. Kharlamov, A. A. Korol, D. P. Kovrizhin, A. S. Kupich, N. A. Melnikova, A. E. Obrazovsky, E. V. Pakhtusova, K.V. Pugachev, S. I. Serednyakov, D. A. Shtol, Z. K. Silagadze, I. K. Surin, Yu. V. Usov, V. N. Zhabin

SciPost Phys. Proc. 16, 014 (2025) · published 14 July 2025 | · pdf

Data with an integrated luminosity of about 370 pb$^{-1}$ have been collected with the SND detector at the VEPP-2000 $e^+e^-$ collider. Here we present recent results on $e^+e^-$ annihilation into hadrons below 2 GeV based on a part of these data. In particular, we discuss measurements of the $e^+e^-\to \pi^+\pi^-$, $e^+e^- \to n\bar{n}$, $e^+e^- \to p\bar{p}$, and $e^+e^-\to \pi^+\pi^-\pi^0\pi^0$ cross sections, and study of the processes $e^+e^-\to \pi^+\pi^-\pi^0$, $e^+e^-\to K^+K^-\pi^0$, $e^+e^- \to \eta\pi^0 \gamma$, and $e^+e^- \to \eta \eta \gamma$.
Is Herbertsmithite far from an ideal antiferromagnet? Ab-initio answer including in-plane Dzyaloshinskii-Moriya interactions and coupling with extra-plane impurities

Flaurent Heully-Alary, Nadia Ben Amor, Nicolas Suaud, Laura Messio, Coen de Graaf, Nathalie Guihéry

SciPost Phys. Core 8, 092 (2025) · published 15 December 2025 | · pdf

Herbertsmithite is known as the archetype of a $S=1/2$ nearest-neighbor Heisenberg antiferromagnet on the kagomé lattice, theoretically presumed to be a quantum gapless spin liquid. However, more and more experiments reveal that the model suffers from deviations from the ideal one, evidenced at very low temperatures. This detailed ab initio study focuses on two such deviations that have never been quantitatively calculated: the anisotropic exchange interactions and the Heisenberg exchange with extra-plane magnetic impurities. The Dzyaloshinskii-Moriya interaction is found to have an in-plane component almost three times larger than the out-of-plane component, but typically obviated in theoretical studies. Moreover, it is shown that the extra-plane magnetic impurities have a strong ferromagnetic interaction (approximatively one third of the main exchange $J_1$) with the kagomé magnetic sites. Combined with an estimated occurrence of these magnetic impurities of $\sim15\%$, the present results indicate that two-dimensional magnetic models only describe part of the physics.
Analytical results for a coagulation/decoagulation model on an inhomogeneous lattice

Nicolas Crampé

SciPost Phys. 2, 006 (2017) · published 24 February 2017 | · pdf

We show that an inhomogeneous coagulation/decoagulation model can be mapped to a quadratic fermionic model via a Jordan-Wigner transformation. The spectrum for this inhomogeneous model is computed exactly and the spectral gap is described for some examples. We construct our inhomogeneous model from two different homogeneous models joined by one special bond (impurity). The homogeneous models we started with are the coagulation/decoagulation models studied previously using the Jordan-Wigner transformation.
Reconstructing hadronically decaying tau leptons with a jet foundation model

Laurits Tani, Joosep Pata, Joschka Birk

SciPost Phys. Core 8, 046 (2025) · published 4 July 2025 | · pdf

The limited availability and accuracy of simulated data has motivated the use of foundation models in high energy physics, with the idea to first train a task-agnostic model on large and potentially unlabeled datasets. This enables the subsequent fine-tuning of the learned representation for specific downstream tasks, potentially requiring much smaller datasets to achieve performance comparable to models trained from scratch on larger datasets. We study how OmniJet-$\alpha$, one of the proposed foundation models for particle jets, can be used on a new set of tasks, and on a new dataset, in order to reconstruct hadronically decaying $\tau$ leptons. We show that the pretraining can successfully be utilized for this multi-task problem, improving the resolution of momentum reconstruction by about $50\%$ when the pretrained weights are fine-tuned, compared to training the model from scratch. While much work remains ahead to develop generic foundation models for high-energy physics, this early result of generalizing an existing model to a new dataset and to previously unconsidered tasks highlights the importance of testing the approaches on a diverse set of datasets and tasks.
Strings and membranes from $\mathcal{A}$-theory five brane

Machiko Hatsuda, Ondřej Hulík, William D. Linch, Warren D. Siegel, Di Wang, Yu-Ping Wang

SciPost Phys. 19, 009 (2025) · published 7 July 2025 | · pdf

The $\mathcal{A}$-theory takes U-duality symmetry as a guiding principle, with the SL(5) U-duality symmetry being described as the world-volume theory of a 5-brane. Furthermore, by unifying the 6-dimensional world-volume Lorentz symmetry with the SL(5) spacetime symmetry, it extends to SL(6) U-duality symmetry. The SL(5) spacetime vielbein fields and the 5-brane world-volume vielbein fields are mixed under the SL(6) U-duality transformation. We demonstrate that consistent sectionings of the SL(6) $\mathcal{A}$5-brane world-volume Lagrangian yield Lagrangians of the $\mathcal{T}$-string with O(D,D) T-duality symmetry, the conventional string, the $\mathcal{M}$5-brane with GL(4) duality symmetry, and the non-perturbative M2-brane in supergravity theory. The GL(4) covariant Lagrangian of the $\mathcal{M}$5-brane derived in this manner is a new, perturbatively quantizable theory.
Measurements of W and Z boson production in ATLAS

Zhibo Wu

SciPost Phys. Proc. 8, 031 (2022) · published 11 July 2022 | · pdf

Precision measurements of the production cross-sections of W and Z boson at LHC provide important tests of perturbative QCD and information about the parton distribution functions for quarks within the proton. We present measurements of cross sections for inclusive $W^+$, $W^{-}$ and Z boson production using data collected by the ATLAS experiment at a center-of-mass energy of $\sqrt{s}$=2.76 TeV. Measurement of the transverse momentum distribution of Z boson at $\sqrt{s}$=13 TeV is also presented. The measurements are corrected for detector effects and compared with state-of-the-art theoretical calculations.
Integrable fishnet circuits and Brownian solitons

Žiga Krajnik, Enej Ilievski, Tomaž Prosen, Benjamin J. A. Héry, Vincent Pasquier

SciPost Phys. 19, 027 (2025) · published 21 July 2025 | · pdf

We introduce classical many-body dynamics on a one-dimensional lattice comprising local two-body maps arranged on discrete space-time mesh that serve as discretizations of Hamiltonian dynamics with arbitrarily time-varying coupling constants. Time evolution is generated by passing an auxiliary degree of freedom along the lattice, resulting in a 'fishnet' circuit structure. We construct integrable circuits consisting of Yang-Baxter maps and demonstrate their general properties, using the Toda and anisotropic Landau-Lifschitz models as examples. Upon stochastically rescaling time, the dynamics is dominated by fluctuations and we observe solitons undergoing Brownian motion.
High-energy logarithmic corrections to the QCD component of same-sign W-pair production

Jeppe R. Andersen, Bertrand Ducloué, Conor Elrick, Andreas Maier, Graeme Nail, Jennifer M. Smillie

SciPost Phys. Proc. 8, 129 (2022) · published 13 July 2022 | · pdf

We describe the calculation of the QCD contribution to same-sign $W$-pair production, $pp\to e^\pm \nu_e \mu^\pm \nu_\mu jj$, resumming all contributions scaling as $\alpha_W^4 \alpha_s^{2+k}\log^k(\hat s/p_\perp^2)$ [arXiv:2107.06818]. These leading logarithmic contributions are enhanced by typical cuts used for Vector Boson Scattering (VBS) studies. We show that while the cross sections are little affected by these corrections, other more exclusive observables relevant for experimental studies are affected more significantly.
On the scalar $\pi K$ form factor beyond the elastic region

Frederic Noël, Leon von Detten, Christoph Hanhart, Martin Hoferichter, Bastian Kubis

SciPost Phys. Proc. 16, 008 (2025) · published 14 July 2025 | · pdf

Pion-kaon ($\pi K$) final states, often appearing in heavy-particle decays at the precision frontier, are important for Standard-Model tests, to describe crossed channels with exotic states, and for spectroscopy of excited kaon resonances. We construct a representation of the $\pi K$ $S$-wave form factor using the elastic $\pi K$ scattering phase shift via dispersion relations in the elastic region and extend this model into the inelastic region using resonance exchange, while maintaining unitarity and the correct analytic structure. As a first application, we successfully described the $\tau \to K_S \pi \nu_\tau$ spectrum to not only achieve a better distinction between $S$- and $P$-wave contributions, but also to provide an improved estimate of the $CP$ asymmetry produced by a tensor operator as well as the forward-backward asymmetry, both of which can be confronted with future data at Belle II. The work presented here is published in [L. von Detten et al., Eur. Phys. J. C 81, 420 (2021)].
A correspondence between the Rabi model and an Ising model with long-range interactions

Bruno Scheihing-Hitschfeld, Néstor Sepúlveda

SciPost Phys. 19, 153 (2025) · published 15 December 2025 | · pdf

By means of Trotter's formula, we show that transition amplitudes between a class of generalized coherent states in the Rabi model can be understood in terms of a certain Ising model featuring long-range interactions beyond nearest neighbors in its thermodynamic limit. Specifically, we relate the transition amplitudes in the Rabi model to a sum over binary variables of the form of a partition function of an Ising model with a number of spin sites equal to the number of steps in Trotter's formula applied to the real-time evolution of the Rabi model. From this, we show that a perturbative expansion in the energy splitting of the two-level subsystem in the Rabi model is equivalent to an expansion in the number of spin domains in the Ising model. We conclude by discussing how calculations in one model give nontrivial information about the other model, and vice versa, as well as applications and generalizations this correspondence may find.

Previous 1 ... 354 355 356 357 358 359 360 361 362 363 364 Next