Hep-Ex explores the fascinating intersection where particle physics meets experimental reality. This field investigates how scientists build massive detectors and accelerate particles to test the fundamental laws of nature, turning abstract theories into measurable data. It is the rigorous process of searching for new particles or forces that could reshape our understanding of the universe, often requiring years of collaboration and engineering.

At Gist.Science, we ensure these discoveries become accessible to everyone. We process every new preprint in this category directly from arXiv, generating both plain-language explanations for curious readers and detailed technical summaries for specialists. Our goal is to bridge the gap between complex experimental results and public understanding without losing scientific nuance.

Below are the latest papers in Hep-Ex, freshly summarized and ready for you to explore.

⚛️ high-energy experiments

Using Graph Neural Networks for hadronic clustering and to reduce beam background in the Belle~II electromagnetic calorimeter

This paper proposes a novel Graph Neural Network approach to mitigate the challenges of increased beam background and irregular hadronic interactions in the Belle~II electromagnetic calorimeter by representing crystal energy depositions as sparse graphs to effectively identify and remove unwanted noise before clustering.

Jonas Eppelt, Torben Ferber2026-04-23
⚛️ nuclear experiments

Observation of impact parameter dependent modifications of nuclear parton distributions in photonuclear Pb+Pb collisions at sNN=5.02\sqrt{s_\mathrm{NN}} = 5.02 TeV with the ATLAS detector

Using 2018 ATLAS data from ultra-peripheral Pb+Pb collisions at 5.02 TeV, this study provides the first experimental observation that nuclear parton distribution modifications vary with impact parameter, evidenced by a significant difference in γ+A\gamma+A jet production cross-sections between collisions with and without forward neutron emission.

ATLAS Collaboration2026-04-23
⚛️ high-energy experiments

Observable CMB B-modes from Cosmological Phase Transitions

This paper demonstrates that tensor perturbations generated during first-order cosmological phase transitions in a secluded dark sector can produce observable CMB B-mode signals comparable to inflationary predictions, potentially complicating the interpretation of future data but offering a way to distinguish the two scenarios through multi-scale measurements.

Kylar Greene, Aurora Ireland, Gordan Krnjaic, Yuhsin Tsai2026-04-22
⚛️ high-energy experiments

Updated model-independent measurement of the strong-phase differences between D0D^0 and Dˉ0→KS/L0π+π−\bar{D}^0 \to K^{0}_{S/L}π^+π^- decays

Using quantum-correlated D0D^0-Dˉ0\bar{D}^0 decays from 7.93 fb−1^{-1} of data collected by the BESIII experiment, this paper presents the most precise model-independent measurement of strong-phase differences for D0→KS/L0π+π−D^0 \to K_{S/L}^0\pi^+\pi^- decays, which are critical inputs for reducing uncertainties in determining the CPCP-violating angle γ\gamma and charm mixing parameters.

BESIII Collaboration, M. Ablikim, M. N. Achasov, P. Adlarson, X. C. Ai, R. Aliberti, A. Amoroso, Q. An, Y. Bai, O. Bakin (…)2026-04-22
⚛️ high-energy experiments

Sampling Off-Axis Neutrino Fluxes with the Short-Baseline Near Detector

This paper demonstrates how the Short-Baseline Near Detector (SBND) can exploit its proximity to the neutrino beam target to sample off-axis flux variations via the SBND-PRISM technique, thereby expanding physics potential and enhancing robustness against cross-section uncertainties while providing publicly available flux data and covariance matrices.

P. Abratenko, R. Acciarri, C. Adams, L. Aliaga-Soplin, O. Alterkait, R. Alvarez-Garrote, D. Andrade Aldana, C. Andreopou (…)2026-04-22
⚛️ high-energy experiments

Muon Beam Dump Experiments explicate five-dimensional nature of U(1)Lμ−LτU(1)_{L_{\mu}-L_{\tau}}

This paper investigates how present and future muon beam dump experiments can probe the five-dimensional nature of U(1)Lμ−LτU(1)_{L_\mu-L_\tau} interactions by leveraging the enhanced signals from multiple Kaluza-Klein gauge bosons and their distinct decay channels to provide direct evidence for extra dimensions while constraining parameters via the muon (g−2)(g-2) anomaly.

Dibyendu Chakraborty, Arindam Chatterjee, Ayushi Kaushik, Kenji Nishiwaki2026-04-22
⚛️ nuclear theory

New Physics Searches via Beam Normal Spin Asymmetry in Bhabha Scattering

This paper investigates the sensitivity of the beam normal spin asymmetry in Bhabha scattering to beyond-the-Standard-Model mediators within the JLab polarized positron program, highlighting how the observable's unique zero crossing in the Standard Model provides a clean, background-free opportunity to significantly extend search ranges for scalar and vector new physics scenarios.

Aleksandr Pustyntsev, Muthubharathi S. Ramasamy, Marc Vanderhaeghen2026-04-22
⚛️ high-energy experiments

Linking Leptogenesis and Asymmetric Dark Matter: A Testable Framework for Neutrino Mass and the Matter-Antimatter Asymmetry

This paper proposes a minimal extension of the Leptogenesis framework that links the generation of the baryon asymmetry and asymmetric dark matter through heavy Majorana neutrino decays, offering a testable TeV-scale mechanism that connects neutrino masses to observable direct detection signals.

Henry G. F. McKenna, Juri Smirnov, Martin Gorbahn2026-04-22
⚛️ quantum physics

Lund Plane to Bloch (LP2B) Encoding for Object and Polarization Tagging with Quantum Jet Substructure

This paper introduces the Lund Plane to Bloch (LP2B) encoding and a corresponding Quantum Tree-Topology Network (QTTN) that maps robust jet kinematics to qubit states, achieving competitive performance in object and polarization tagging with significantly fewer parameters and reduced systematic uncertainties compared to classical deep learning models, while also being validated on real quantum hardware.

Fabrizio Napolitano, Luca Della Penna, Tommaso Tedeschi, Livio Fanò2026-04-22