Evidence for light-by-light scattering in heavy-ion collisions with the ATLAS detector at the LHC

Aaboud, M.; Aad, G.; Abbott, B.; Abdallah, J.; Abdinov, O.; Abeloos, B.; Abidi, S.; AbouZeid, O.; Abraham, N.; Abramowicz, H.; Abreu, H.; Abreu, R.; Abulaiti, Y.; Acharya, B.; Adachi, S.; Adamczyk, L.; Adelman, J.; Adersberger, M.; Adye, T.; Affolder, A.; et al.

Please use this identifier to cite or link to this item: https://hdl.handle.net/2440/114964

Scopus	Web of Science®	Altmetric
Citations
?	?

Type:	Journal article
Title:	Evidence for light-by-light scattering in heavy-ion collisions with the ATLAS detector at the LHC
Author:	Aaboud, M. Aad, G. Abbott, B. Abdallah, J. Abdinov, O. Abeloos, B. Abidi, S. AbouZeid, O. Abraham, N. Abramowicz, H. Abreu, H. Abreu, R. Abulaiti, Y. Acharya, B. Adachi, S. Adamczyk, L. Adelman, J. Adersberger, M. Adye, T. Affolder, A. et al.
Citation:	Nature Physics, 2017; 13(9):852-858
Publisher:	Springer Nature
Issue Date:	2017
ISSN:	1745-2473 1745-2481
Statement of Responsibility:	M. Aaboud ... P. Jackson ... L. Lee ... A. Petridis ... M.J. White ... [et al.] (The ATLAS Collaboration)
Abstract:	Light-by-light scattering (γγ → γγ) 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 (γγ) → Pb(∗) + Pb(∗)γγ, for photon transverse energy ET > 3 GeV, photon absolute pseudorapidity \|η\| < 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.
Rights:	© 2017 Macmillan Publishers Limited, part of Springer Nature. All rights reserved. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.
DOI:	10.1038/nphys4208
Grant ID:	ARC
Published version:	http://dx.doi.org/10.1038/nphys4208
Appears in Collections:	Aurora harvest 8 Physics publications

Files in This Item:

File	Description	Size	Format
hdl_114964.pdf	Published version	528.11 kB	Adobe PDF	View/Open

Show full item record

Adelaide Research & Scholarship