⚛️ Category

hep-ex

1434 papers

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.

Scalable Multi-Task Learning for Particle Collision Event Reconstruction with Heterogeneous Graph Neural Networks

This paper proposes a scalable Heterogeneous Graph Neural Network (HGNN) that employs a multi-task learning paradigm to simultaneously perform particle vertex association and graph pruning, thereby significantly improving beauty hadron reconstruction performance and inference efficiency for complex particle collision events at the Large Hadron Collider.

William Sutcliffe, Marta Calvi, Simone Capelli, Jonas Eschle, Julián García Pardiñas, Abhijit Mathad, Azusa Uzuki, Nicola Serra2026-03-09⚛️ hep-ex

System size and event shape dependence of particle-identified balance functions in proton-proton collisions at s=13\sqrt{s} = 13 TeV using PYTHIA 8 and EPOS models

This study utilizes PYTHIA 8 and EPOS-LHC models to demonstrate that particle-identified balance functions in 13 TeV proton-proton collisions exhibit distinct dependencies on event multiplicity and spherocity, revealing that while PYTHIA 8 reflects fragmentation-dominated dynamics, EPOS-LHC captures collective effects like radial flow and diffusion that mimic heavy-ion behavior, thereby offering a powerful tool to disentangle hadronization mechanisms and medium-like collectivity in small collision systems.

Subash Chandra Behera, Arvind Khuntia2026-03-09⚛️ hep-ph

Search for Signatures of Dark Matter Annihilation in the Galactic Center with HAWC

Using 8 years of data from the HAWC Observatory, researchers conducted an indirect search for dark matter annihilation in the Galactic Center across masses from 1 TeV to 10 PeV, finding no significant excess and establishing the first gamma-ray constraints on particles above 100 TeV with upper limits on the annihilation cross section of approximately 10−2410^{-24} cm3^3/s.

R. Alfaro, C. Alvarez, A. Andrés, E. Anita-Rangel, M. Araya, J. C. Arteaga-Velázquez, D. Avila Rojas, H. A. Ayala Solares, R. Babu, P. Bangale, A. Bernal, K. S. Caballero-Mora, T. Capistrán, A. (…)2026-03-09⚛️ hep-ph

A model-independent measurement of the CKM angle γ\gamma in the decays B±→[K+K−π+π−]Dh±B^\pm\to[K^+K^-\pi^+\pi^-]_D h^\pm and B±→[π+π−π+π−]Dh±B^\pm\to[\pi^+\pi^-\pi^+\pi^-]_D h^\pm (h=K,πh = K, \pi)

Using 9 fb−1^{-1} of LHCb proton-proton collision data, this paper presents the first phase-space-binned, model-independent measurement of the CKM angle γ\gamma in B±→[K+K−π+π−]Dh±B^\pm\to[K^+K^-\pi^+\pi^-]_D h^\pm and B±→[π+π−π+π−]Dh±B^\pm\to[\pi^+\pi^-\pi^+\pi^-]_D h^\pm decays, yielding a result of 53.9∘53.9^\circ that, when combined with existing integrated measurements, achieves one of the most precise determinations of γ\gamma to date at 52.6∘52.6^\circ.

LHCb collaboration, R. Aaij, 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. Ajaltouni, S. (…)2026-03-09⚛️ hep-ex

Response of wavelength-shifting and scintillating-wavelength-shifting fibers to ionizing radiation

This study characterizes the light yield and transmission properties of Saint-Gobain's BCF-91A and Eljen Technology's new EJ-160 wavelength-shifting fibers under ionizing radiation, revealing that the EJ-160 variants offer significantly higher light yields (5–7 times greater) despite varying attenuation lengths.

W. Bae, J. Cesar, K. Chen, J. Cho, D. Du, J. Edgar, L. Earthman, O. M. Falana, M. Gajda, C. Hurlbut, M. Jackson, K. Lang, C. Lee, J. Y. Lee, E. Liang, J. Liu, C. Maxwell, C. Murthy, D. Myers, S. Nguye (…)2026-03-09🔬 physics

Position-Sensitive Silicon Photomultiplier Array with Enhanced Position Reconstruction by means of a Deep Neural Network

This paper demonstrates that applying Deep Neural Networks to a 2x2 array of linearly-graded Silicon Photomultipliers significantly improves position resolution and linearity while increasing the number of resolvable pixels by a factor of 5.7 to 12.1 compared to traditional reconstruction methods.

Cyril Alispach, Fabio Acerbi, Hossein Arabi, Domenico della Volpe, Alberto Gola, Aramis Raiola, Habib Zaidi2026-03-09🔬 physics

Measurement of the branching fraction of η→μ+μ−\eta \to \mu^+ \mu^- and search for η→e+e−\eta \to e^+ e^-

Using a sample of approximately 10 million J/ψJ/\psi events collected by the BESIII detector, this study measures the branching fraction of η→μ+μ−\eta \to \mu^+ \mu^- to be (5.8±1.0stat±0.2syst)×10−6(5.8 \pm 1.0_{\rm stat} \pm 0.2_{\rm syst}) \times 10^{-6} and sets an improved 90% confidence level upper limit of 2.2×10−72.2 \times 10^{-7} for the η→e+e−\eta \to e^+ e^- decay.

BESIII Collaboration, M. Ablikim, M. N. Achasov, P. Adlarson, X. C. Ai, R. Aliberti, A. Amoroso, Q. An, Y. Bai, O. Bakina, Y. Ban, H. -R. Bao, V. Batozskaya, K. Begzsuren, N. Berger, M. Berlowski, M. (…)2026-03-09⚛️ hep-ex

First results of a Monolithic Active Pixel Sensor with Internal Signal Gain Fully Integrated in a 180 nm CMOS Technology

This paper presents the first results of the CASSIA sensor, a novel monolithic active pixel sensor fabricated in 180 nm CMOS technology that utilizes fully integrated internal gain layers to achieve signal amplification, enabling operation in both low-gain proportional and high-gain single-photon avalanche modes for improved timing resolution and pile-up mitigation in high-luminosity particle physics experiments.

Heinz Pernegger (CERN, Experimental Physics Department, Geneva, Switzerland), Emma Kate Anderson (CERN, Experimental Physics Department, Geneva, Switzerland), Paula Bartulovic (University of Zagreb (…)2026-03-09🔬 physics