TY - JOUR
T1 - Observation of Light-by-Light Scattering in Ultraperipheral Pb plus Pb Collisions with the ATLAS Detector
AU - Aad, G.
AU - Abbott, B.
AU - Abbott, DC
AU - Abdinov, O.
AU - Abud, AA
AU - Abeling, K.
AU - Abhayasinghe, DK
AU - Abidi, S.H.
AU - AbouZeid, Ossama Sherif Alexander
AU - Abraham, NL
AU - Abramowicz, H.
AU - Abreu, H.
AU - Abulaiti, Y.
AU - Acharya, B.S.
AU - Achkar, B.
AU - Adachi, Sosuke
AU - Adam, Luise
AU - Bourdarios, CA
AU - Besjes, Geert-Jan
AU - Alonso Diaz, Alejandro
AU - Camplani, Alessandra
AU - Dam, Mogens
AU - de Almeida Dias, Flavia
AU - Galster, Gorm Aske Gram Krohn
AU - Hansen, Jørn Dines
AU - Hansen, Jørgen Beck
AU - Hansen, Peter Henrik
AU - Monk, James William
AU - hqz214, hqz214
AU - Bajic, Milena
AU - Ignazzi, Rosanna
AU - Wiglesworth, Graig
AU - Petersen, Troels Christian
AU - Stark, Simon Holm
AU - Xella, Stefania
AU - ATLAS Collaboration
PY - 2019/7/31
Y1 - 2019/7/31
N2 - This Letter describes the observation of the light-by-light scattering process, γγ→γγ, in Pb+Pb collisions at sNN=5.02 TeV. The analysis is conducted using a data sample corresponding to an integrated luminosity of 1.73 nb-1, collected in November 2018 by the ATLAS experiment at the LHC. Light-by-light scattering candidates are selected in events with two photons produced exclusively, each with transverse energy ETγ>3 GeV and pseudorapidity |ηγ|<2.4, diphoton invariant mass above 6 GeV, and small diphoton transverse momentum and acoplanarity. After applying all selection criteria, 59 candidate events are observed for a background expectation of 12±3 events. The observed excess of events over the expected background has a significance of 8.2 standard deviations. The measured fiducial cross section is 78±13(stat)±7(syst)±3(lumi) nb.
AB - This Letter describes the observation of the light-by-light scattering process, γγ→γγ, in Pb+Pb collisions at sNN=5.02 TeV. The analysis is conducted using a data sample corresponding to an integrated luminosity of 1.73 nb-1, collected in November 2018 by the ATLAS experiment at the LHC. Light-by-light scattering candidates are selected in events with two photons produced exclusively, each with transverse energy ETγ>3 GeV and pseudorapidity |ηγ|<2.4, diphoton invariant mass above 6 GeV, and small diphoton transverse momentum and acoplanarity. After applying all selection criteria, 59 candidate events are observed for a background expectation of 12±3 events. The observed excess of events over the expected background has a significance of 8.2 standard deviations. The measured fiducial cross section is 78±13(stat)±7(syst)±3(lumi) nb.
U2 - 10.1103/PhysRevLett.123.052001
DO - 10.1103/PhysRevLett.123.052001
M3 - Journal article
C2 - 31491300
SN - 0031-9007
VL - 123
JO - Physical Review Letters
JF - Physical Review Letters
IS - 5
M1 - 052001
ER -