Observation of quantum effects on radiation reaction in strong fields
Journal article, 2026
Radiation reaction, the force experienced by an accelerated charge due to radiation emission, has long been the subject of extensive theoretical and experimental research. Experimental verification of a quantum, strong-field description of radiation reaction is fundamentally important, and has wide-ranging implications for astrophysics, laser-driven particle acceleration, next-generation particle colliders and inverse-Compton photon sources for medical and industrial applications. However, the difficulty of accessing regimes where strong field and quantum effects dominate inhibited previous efforts to observe quantum radiation reaction in charged particle dynamics with high significance. We report a high significance (> 5σ) observation of strong-field radiation reaction on electron spectra where quantum effects are substantial. We obtain quantitative, strong evidence favouring the quantum-continuous and quantum-stochastic models over the classical model; the quantum models perform comparably. The lower electron energy losses predicted by the quantum models account for their improved performance. Model comparison was performed using a novel Bayesian framework, which has widespread utility for laser-particle collision experiments, including those utilising conventional accelerators, where some collision parameters cannot be measured directly.
Author
Eva E. Los
Imperial College London
E. Gerstmayr
Queen's University Belfast
Imperial College London
Stanford University
C. Arran
University of York
M. J.V. Streeter
Queen's University Belfast
Cary Colgan
Tokamak Energy Ltd
Imperial College London
Claudia C. Cobo
University of York
Imperial College London
Brendan Kettle
Imperial College London
Tom Blackburn
University of Gothenburg
Nicolas Bourgeois
STFC Rutherford Appleton Laboratory
Luke Calvin
Queen's University Belfast
Jason Cardarelli
Michigan Engineering
Niall Cavanagh
Queen's University Belfast
Stephen J.D. Dann
STFC Rutherford Appleton Laboratory
Antonino Di Piazza
Max Planck Society
University of Rochester
Rebecca Fitzgarrald
Michigan Engineering
Antony Ilderton
University of Edinburgh
Christoph H. Keitel
Max Planck Society
Mattias Marklund
Chalmers, Physics
University of Gothenburg
P. McKenna
University of Strathclyde
C. D. Murphy
University of York
Z. Najmudin
Imperial College London
Peter Parsons
STFC Rutherford Appleton Laboratory
Queen's University Belfast
Paramel Pattathil Rajeev
STFC Rutherford Appleton Laboratory
D. R. Symes
STFC Rutherford Appleton Laboratory
Matteo Tamburini
Max Planck Society
A. G. R. Thomas
Michigan Engineering
J. C. Wood
Deutsches Elektronen-Synchrotron (DESY)
Imperial College London
M. Zepf
Friedrich Schiller University Jena
Helmholtz Association of German Research Centres
G. Sarri
Queen's University Belfast
C. P. Ridgers
University of York
S. P. D. Mangles
Imperial College London
Nature Communications
2041-1723 (ISSN) 20411723 (eISSN)
Vol. 17 1 1157Subject Categories (SSIF 2025)
Atom and Molecular Physics and Optics
Fusion, Plasma and Space Physics
Subatomic Physics
DOI
10.1038/s41467-025-67918-8
PubMed
41530130