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

Search for Lorentz-boosted di-τ\tau resonances produced in association with top quark pairs in s=13\sqrt{s}=13 TeV pp collisions with the ATLAS detector

Using 140 fb1^{-1} of 13 TeV proton-proton collision data collected by the ATLAS detector, this study presents a search for Lorentz-boosted pseudoscalar resonances decaying into hadronic τ\tau-lepton pairs in association with top quark pairs, finding no significant deviation from the Standard Model and setting upper limits on the production cross-section for masses between 20 and 85 GeV.

ATLAS Collaboration2026-07-31
⚛️ nuclear experiments

Extraction of σTT\sigma_{TT} for Proton, Neutron, Deuteron and 3^3He from Quasi-real Photon Scattering

This paper reports the extraction of polarized photoproduction cross-sections for the proton, neutron, deuteron, and 3^3He by extrapolating electron scattering data from Jefferson Lab experiments to the real photon point, revealing that while proton results align with real photon data, the neutron and deuteron exhibit enhanced strength in the Δ(1232)\Delta(1232) region that better supports isospin symmetry.

YiLei Li, B. Callahan, M. M. Dalton, A. Deur, O. Larson, A. Rask, D. W. Upton, X. Zheng2026-07-31
⚛️ high-energy experiments

Search for exotic Higgs boson decays H \to AA\mathcal{AA} with AA\mathcal{AA} \to γγ\gamma\gamma in events with a semi-merged topology in proton-proton collisions at s\sqrt{s} = 13 TeV

Using 138 fb1^{-1} of proton-proton collision data at s\sqrt{s} = 13 TeV collected by the CMS experiment, this study searches for exotic Higgs boson decays into two light particles (A\mathcal{A}) that subsequently decay into four photons, where one A\mathcal{A} produces a semi-merged diphoton system and the other yields two resolved photons, finding no evidence of such events and setting the most stringent limits to date on the production cross section times branching fraction for A\mathcal{A} masses between 1 and 5 GeV.

CMS Collaboration2026-07-30
⚛️ high-energy experiments

Evidence for the rare decay B+Λˉpμ+μB^{+} \to \bar \Lambda p \mu^{+} \mu^{-}

Using LHCb proton-proton collision data at 13 TeV, researchers report evidence for the rare decay B+Λˉpμ+μB^{+} \to \bar \Lambda p \mu^{+} \mu^{-} with a significance of 3.5 standard deviations in the low invariant-mass region of the Λˉp\bar \Lambda p system, measuring a branching fraction of approximately 1.70×1081.70 \times 10^{-8} while setting upper limits for the high-mass region.

LHCb collaboration, R. Aaij, A. S. W. Abdelmotteleb, C. Abellan Beteta, F. Abudinén, T. Ackernley, A. A. Adefisoye, B. A (…)2026-07-30
⚛️ lattice

Lattice determination of the neutrino background for J/ψγ+invisibleJ/ψ\rightarrow γ+ \textrm{invisible}

This paper presents the first lattice QCD calculation of the irreducible Standard Model background for the decay J/ψγννˉJ/\psi \to \gamma \nu\bar{\nu}, determining its branching fraction to be 1.04(7)(8)×10101.04(7)(8)\times 10^{-10} and providing a critical theoretical benchmark for future dark matter searches via radiative invisible quarkonium decays.

Yu Meng, Ning Li, Chuan Liu, Haobo Yan, Ke-Long Zhang, Xue-Ze Zhang2026-07-30
⚛️ high-energy experiments

Automated NRQCD and NRQED simulations of quarkonium and leptonium production with P-wave states and physical-mass effects

This paper introduces the MadSONS module for MadGraph5_aMC@NLO, which automates the simulation of quarkonium and leptonium production by extending previous S-wave capabilities to include P-wave states via dual-number derivatives and physical-mass effects, thereby improving the description of LHCb data for J/ψ+ψ(2S)J/\psi + \psi(2{\rm S}) production.

Luca Maxia, Hua-Sheng Shao, Lukas Simon2026-07-30
⚛️ high-energy experiments

Improved analysis of non-resonant Higgs boson pair production in the bbˉτ+τb\bar{b}\tau^+\tau^- final state with $196$ fb1^{-1} of data collected at s\sqrt{s} = 13 TeV and 13.6 TeV with the ATLAS detector

Using an updated dataset of 196 fb⁻¹ collected at 13 TeV and 13.6 TeV, the ATLAS collaboration reports a non-resonant Higgs boson pair production cross-section consistent with Standard Model expectations and derives new constraints on the Higgs self-coupling modifier, while also validating the analysis strategy through measurements of ZH and ZZ processes.

ATLAS Collaboration2026-07-30
⚛️ high-energy experiments

Deep-learning jet flavor tagging for precision hadronic Higgs measurements at future e+ee^+e^- Higgs factories

This paper demonstrates that employing state-of-the-art deep-learning jet flavor taggers combined with XGBoost classifiers at a future e+ee^+e^- Higgs factory operating at 240 GeV with 20 ab1^{-1} luminosity significantly improves the precision of measuring Higgs decays to ccˉc\bar{c} and $gg$ while enabling the first quantitative sensitivity estimate for the challenging HssˉH\to s\bar{s} channel.

Xinzhu Wang, Yifan Zhu, Chunxiang Zhu, Jianfeng Jiang, Manqi Ruan, Kun Wang, Haijun Yang, Yongfeng Zhu2026-07-29