@Article{ATLASCollaborationAaboud_etal2017, author="ATLAS Collaboration (Aaboud, M. et al and Alvarez Piqueras, D. and Barranco Navarro, L. and Cabrera Urban, S. and Castillo Gimenez, V. and Cerda Alberich, L. and Costa, M. J. and Fernandez Martinez, P. and Ferrer, A. and Fiorini, L. and Fuster, J. and Garcia, C. and Garcia Navarro, J. E. and Gonzalez de la Hoz, S. and Higon-Rodriguez, E. and Jimenez Pena, J. and Lacasta, C. and Mamuzic, J. and Marti-Garcia, S. and Melini, D. and Mitsou, V. A. and Pedraza Lopez, S. and Rodriguez Rodriguez, D. and Romero Adam, E. and Salt, J. and Sanchez Martinez, V. and Soldevila, U. and Sanchez, J. and Valero, A. and Valls Ferrer, J. A. and Vos, M.", title="Evidence for light-by-light scattering in heavy-ion collisions with the ATLAS detector at the LHC", journal="Nature Physics", year="2017", publisher="Nature Publishing Group", volume="13", number="9", pages="852--858", abstract="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 $\mu$b(-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.", optnote="WOS:000409235100017", optnote="exported from refbase (https://references.ific.uv.es/refbase/show.php?record=3287), last updated on Wed, 20 Sep 2017 11:40:47 +0000", issn="1745-2473", doi="10.1038/NPHYS4208", opturl="http://arxiv.org/abs/1702.01625", opturl="https://doi.org/10.1038/NPHYS4208", archivePrefix="arXiv", eprint="1702.01625", language="English" }