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.

Kitchen Sink Anomaly Detection

This paper addresses limitations in existing resonant anomaly detection methods by introducing new simulated signal benchmarks and a comprehensive "kitchen sink" observable set combining Energy Flow Polynomials and subjettiness variables, demonstrating that this approach offers superior sensitivity across diverse signal types while an attribute bagging variant significantly reduces training costs with comparable performance.

Ranit Das, Marie Hein, Gregor Kasieczka, Michael Krämer, Lukas Lang, Radha Mastandrea, Louis Moureaux, Alexander Mück, David Shih2026-04-24⚛️ hep-ph

Search for dark matter produced in association with a dark Higgs boson decaying into a bottom quark-antiquark pair in proton-proton collisions at s\sqrt{s} = 13 TeV

Using 138 fb1^{-1} of proton-proton collision data at 13 TeV collected by the CMS detector, this study sets the most stringent limits to date on dark matter production associated with a dark Higgs boson decaying into a bottom quark-antiquark pair, excluding mediator masses up to 4.5 TeV for specific dark Higgs mass hypotheses.

CMS Collaboration2026-04-24⚛️ hep-ex

Masked-Token Prediction for Anomaly Detection at the Large Hadron Collider

This paper introduces the first application of masked-token prediction, a technique adapted from Large Language Models, to anomaly detection at the Large Hadron Collider, demonstrating that a lightweight transformer trained solely on Standard Model background events can effectively identify rare new-physics signals through deviations in learned data structures.

Ambre Visive, Roberto Ruiz de Austri, Polina Moskvitina, Clara Nellist, Sascha Caron2026-04-24⚛️ hep-ph

Performance of the LHCb muon detector in Run 3

This paper presents the operation, calibration, and performance evaluation of the upgraded LHCb muon detector during Run 3, demonstrating that despite a fivefold increase in instantaneous luminosity, the system achieves a muon identification efficiency above 90% with sub-percent hadron misidentification probability.

P. Albicocco, M. Anelli, F. Archilli, M. Atzeni, W. Baldini, A. Balla, S. Belin, N. Bondar, D. Brundu, S. Cadeddu, S. Calì, A. Cardini, M. Carletti, A. Casais Vidal, V. Chulikov, A. Chubykin, P. Cia (…)2026-04-24⚛️ hep-ex

Neutron Portal and Dark Matter-Baryon Coincidence: from UV Completion to Phenomenology

This paper proposes a dynamical framework linking the dark matter-baryon coincidence to a GeV-scale asymmetric dark matter scenario, where a strongly supercooled dark confinement phase transition—potentially responsible for observed nano-Hz gravitational waves—naturally correlates the dark matter mass with the ultraviolet completion of the neutron portal operator.

Sudhakantha Girmohanta, Yuichiro Nakai, Yoshihiro Shigekami, Zhihao Zhang2026-04-24⚛️ hep-ph

Observation of a new excited charm-strange meson Ds1(2933)+D_{s1}(2933)^+ in B0D+DK+πB^0\to D^+ D^- K^+ \pi^- decays

Using 13 TeV proton-proton collision data from the LHCb experiment, researchers observed a new excited charm-strange meson, Ds1(2933)+D_{s1}(2933)^+, with a statistical significance exceeding 10 standard deviations, measuring its mass at approximately 2933 MeV and identifying it as a candidate for a Ds(2P1())+D_s(2P^{(\prime)}_{1})^+ state with JP=1+J^P = 1^+.

LHCb collaboration, R. Aaij, M. Abdelfatah, A. S. W. Abdelmotteleb, C. Abellan Beteta, F. Abudinén, T. Ackernley, A. A. Adefisoye, B. Adeva, M. Adinolfi, P. Adlarson, C. Agapopoulou, C. A. Aidala, Z (…)2026-04-24⚛️ hep-ex

Liquid argon purification and purity monitoring: apparatus and first results

This paper reports the design and initial performance of a 13-liter liquid argon test stand at Wellesley College, which successfully achieved an oxygen-equivalent impurity concentration of 0.25 ppb and an electron lifetime of 1.2 ms to support R&D for future large-scale liquid argon time projection chambers.

Wenzhao Wei, I-see Warisa Jaidee, Spencer Dockal, Vyara T. Tsvetkova, Genevieve Bui, Tenaya Chen Lin, Lucia Epstein, Ava Faubus, Neneh M. T. Hambraeus, Sushine B. Lyon, Diana Lopez, Natalie McGee, Pip (…)2026-04-24⚛️ hep-ex

Precision measurement of positron decay modes of Xe-125 in the LUX-ZEPLIN experiment

The LUX-ZEPLIN experiment reports the first direct constraint on the individual positron emission branching levels of the activation product 125Xe^{125}\text{Xe}, measuring a total branching ratio of 0.29±0.08stat.±0.04sys.0.29\pm0.08_{\text{stat.}}\pm0.04_{\text{sys.}} % with a statistical significance of 5.5σ\sigma.

D. S. Akerib, A. K. Al Musalhi, F. Alder, B. J. Almquist, C. S. Amarasinghe, A. Ames, T. J. Anderson, N. Angelides, H. M. Araújo, J. E. Armstrong, M. Arthurs, A. Baker, S. Balashov, J. Bang, J. W. B (…)2026-04-24⚛️ hep-ex