%0 Journal Article %T Evidence for light-by-light scattering in heavy-ion collisions with the ATLAS detector at the LHC %A ATLAS Collaboration (Aaboud, M. et al %A Alvarez Piqueras, D. %A Barranco Navarro, L. %A Cabrera Urban, S. %A Castillo Gimenez, V. %A Cerda Alberich, L. %A Costa, M. J. %A Fernandez Martinez, P. %A Ferrer, A. %A Fiorini, L. %A Fuster, J. %A Garcia, C. %A Garcia Navarro, J. E. %A Gonzalez de la Hoz, S. %A Higon-Rodriguez, E. %A Jimenez Pena, J. %A Lacasta, C. %A Mamuzic, J. %A Marti-Garcia, S. %A Melini, D. %A Mitsou, V. A. %A Pedraza Lopez, S. %A Rodriguez Rodriguez, D. %A Romero Adam, E. %A Salt, J. %A Sanchez Martinez, V. %A Soldevila, U. %A Sanchez, J. %A Valero, A. %A Valls Ferrer, J. A. %A Vos, M. %J Nature Physics %D 2017 %V 13 %N 9 %I Nature Publishing Group %@ 1745-2473 %G English %F ATLASCollaborationAaboud_etal2017 %O WOS:000409235100017 %O exported from refbase (https://references.ific.uv.es/refbase/show.php?record=3287), last updated on Wed, 20 Sep 2017 11:40:47 +0000 %X Light-by-light scattering (gamma gamma -> gamma gamma) is a quantum-mechanical process that is forbidden in the classical theory of electrodynamics. This reaction is accessible at the Large Hadron Collider thanks to the large electromagnetic field strengths generated by ultra-relativistic colliding lead ions. Using 480 μb(-1) of lead-lead collision data recorded at a centre-of-mass energy per nucleon pair of 5.02 TeV by the ATLAS detector, here we report evidence for light-by-light scattering. A total of 13 candidate events were observed with an expected background of 2.6 +/- 0.7 events. After background subtraction and analysis corrections, the fiducial cross-section of the process Pb + Pb (gamma gamma) -> Pb-(center dot) + Pb-(center dot) gamma gamma, for photon transverse energy E-T > 3 GeV, photon absolute pseudorapidity vertical bar eta vertical bar < 2.4, diphoton invariant mass greater than 6 GeV, diphoton transverse momentum lower than 2 GeV and diphoton acoplanarity below 0.01, is measured to be 70 +/- 24 (stat.) +/- 17 (syst.) nb, which is in agreement with the standard model predictions. %R 10.1038/NPHYS4208 %U http://arxiv.org/abs/1702.01625 %U https://doi.org/10.1038/NPHYS4208 %P 852-858