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

M. Aaboud N. Berger 1 A.M. Burger 1 M. Delmastro 1 L. Di Ciaccio 1 S. Elles 1 K. Grevtsov 1 T. Guillemin 1 T. Hryn’ova 1 S. Jézéquel 1 O. Kivernyk 1 I. Koletsou 1 R. Lafaye 1 J. Levêque 1 N. Lorenzo Martinez 1 P. Mastrandea 1 E. Sauvan 1 B.H. Smart 1 S. Todorova-Nova 1 A. Vallier 1 I. Wingerter-Seez 1 E. Yatsenko 1 S. Berlendis 2 C. Camincher 2 J. Collot 2 S. Crépé-Renaudin 2 P.A. Delsart 2 C. Gabaldon 2 M.H. Genest 2 J.Y. Hostachy 2 F. Ledroit-Guillon 2 A. Lleres 2 A. Lucotte 2 F. Malek 2 T. Meideck 2 E. Petit 2 J. Stark 2 B. Trocmé 2 D. Boumediene 3 E. Busato 3 D. Calvet 3 S. Calvet 3 A.R. Chomont 3 J. Donini 3 S. Ganguly 3 Ph. Gris 3 R. Madar 3 M. Marjanovic 3 D. Pallin 3 S.M. Romano Saez 3 C. Santoni 3 F. Vazeille 3 G. Aad 4 M. Alstaty 4 M. Barbero 4 A. Calandri 4 T.P. Calvet 5 Y. Coadou 4 K. de Vasconcelos Corga 4 C. Diaconu 4 R. El Kosseifi 4 V. Ellajosyula 4 F. Djama 4 L. Feligioni 4 A. Hadef 4 G.D. Hallewell 4 F. Hubaut 4 S.J. Kahn 4 E. B. F. G. Knoops 4 R. Kukla 4 E. Le Guirriec 4 K. Liu 4 D. Madaffari 4 E. Monnier 4 S. Muanza 4 E. Nagy 4 P. Pralavorio 4 Y. Rodina 4 A. Rozanov 4 M. Talby 4 T. Theveneaux-Pelzer 4 R.E. Ticse Torres 4 S. Tisserant 4 J. Toth 6, 4 F. Touchard 4 L. Vacavant 4 R. Wolff 4
Abstract : Light-by-light scattering ($\gamma\gamma\rightarrow\gamma\gamma$) 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 (Pb) ions. Using 480 $\mu$b$^{-1}$ of Pb+Pb collision data recorded at a centre-of-mass energy per nucleon pair of 5.02 TeV by the ATLAS detector, the ATLAS Collaboration reports evidence for the $\gamma\gamma\rightarrow\gamma\gamma$ reaction. A total of 13 candidate events are observed with an expected background of 2.6$\pm$0.7 events. After background subtraction and analysis corrections, the fiducial cross section of the process $\textrm{Pb+Pb}\,(\gamma\gamma)\rightarrow \textrm{Pb}^{(\ast)}\textrm{+}\textrm{Pb}^{(\ast)}\,\gamma\gamma$, for photon transverse energy $E_{\mathrm{T}}>$3 GeV, photon absolute pseudorapidity $|\eta|<$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 $\pm$ 24 (stat.) $\pm$ 17 (syst.) nb, which is in agreement with Standard Model predictions.
Liste complète des métadonnées

http://hal.in2p3.fr/in2p3-01458929
Contributeur : Claudine Bombar <>
Soumis le : mardi 7 février 2017 - 10:01:24
Dernière modification le : jeudi 18 janvier 2018 - 01:49:01

Identifiants

Citation

M. Aaboud, N. Berger, A.M. Burger, M. Delmastro, L. Di Ciaccio, et al.. Evidence for light-by-light scattering in heavy-ion collisions with the ATLAS detector at the LHC. Nature Physics, Nature Publishing Group, 2017, 13, pp.852-858. 〈https://www.nature.com/nphys/journal/v13/n9/full/nphys4208.html〉. 〈10.1038/nphys4208〉. 〈in2p3-01458929〉

Partager

Métriques

Consultations de la notice

235