Observation of Light-by-Light Scattering in Ultraperipheral Pb+Pb Collisions with the ATLAS Detector

ATLAS Collaboration

doi:10.1103/PhysRevLett.123.052001

Observation of Light-by-Light Scattering in Ultraperipheral Pb+Pb Collisions with the ATLAS Detector

ATLAS Collaboration

iThemba Labs
Department of Physics
University of South Africa
Cadi Ayyad University
Moroccan Foundation for Advanced Science Innovation and Research (MAScIR)
Dep Física and CEFITEC of Faculdade de Ciências e Tecnologia
NOVA University Lisbon
CERN
Aix-Marseille Université
University of Oklahoma
University of Massachusetts
Azerbaijan National Academy of Sciences
National Institute for Nuclear Physics
University of Pavia
University of Göttingen
Royal Holloway University of London
University of Toronto
University of Copenhagen
University of Sussex
Tel Aviv University
Technion-Israel Institute of Technology
Argonne National Laboratory
Abdus Salam International Centre for Theoretical Physics
The University of Tokyo
Johannes Gutenberg University Mainz
IN2P3/CNRS
AGH University of Krakow
Northern Illinois University
Ludwig Maximilian University of Munich
Bogazici University
University of Geneva
Rutherford Appleton Laboratory
University of California at Santa Cruz
Université Clermont Auvergne
Radboud University Nijmegen
Alexandru Ioan Cuza University of Iaşi
Laboratório de Instrumentação e Física Experimental de Partículas
University of Granada
Joint Institute for Nuclear Research
McGill University
CAS - Institute of High Energy Physics
University of Rome Tor Vergata
Kyoto University
Lund University
P.N. Lebedev Physical Institute of the Russian Academy of Sciences
University of Bologna
University of Victoria BC

Research output: Contribution to journal › Article › peer-review

174 Scopus citations

Abstract

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.

Original language	English
Article number	052001
Journal	Physical Review Letters
Volume	123
Issue number	5
DOIs	https://doi.org/10.1103/PhysRevLett.123.052001
State	Published - Jul 31 2019

Access to Document

10.1103/PhysRevLett.123.052001

Cite this

@article{1944b1bdb6084fcba04f586bd7097200,

title = "Observation of Light-by-Light Scattering in Ultraperipheral Pb+Pb Collisions with the ATLAS Detector",

abstract = "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.",

author = "\{ATLAS Collaboration\} and G. Aad and B. Abbott and Abbott, \{D. C.\} and O. Abdinov and \{Abed Abud\}, A. and K. Abeling and Abhayasinghe, \{D. K.\} and Abidi, \{S. H.\} and Abouzeid, \{O. S.\} and Abraham, \{N. L.\} and H. Abramowicz and H. Abreu and Y. Abulaiti and Acharya, \{B. S.\} and B. Achkar and S. Adachi and L. Adam and \{Adam Bourdarios\}, C. and L. Adamczyk and L. Adamek and J. Adelman and M. Adersberger and A. Adiguzel and S. Adorni and T. Adye and Affolder, \{A. A.\} and Y. Afik and C. Agapopoulou and Agaras, \{M. N.\} and A. Aggarwal and C. Agheorghiesei and Aguilar-Saavedra, \{J. A.\} and F. Ahmadov and Ahmed, \{W. S.\} and X. Ai and G. Aielli and S. Akatsuka and {\AA}kesson, \{T. P.A.\} and E. Akilli and Akimov, \{A. V.\} and \{Al Khoury\}, K. and Alberghi, \{G. L.\} and J. Albert and H. Arnold and \{Da Via\}, C. and V. Dao and J. Hobbs and J. Jia and G. Piacquadio and D. Tsybychev",

note = "Publisher Copyright: {\textcopyright} 2019 CERN.",

year = "2019",

month = jul,

day = "31",

doi = "10.1103/PhysRevLett.123.052001",

language = "English",

volume = "123",

journal = "Physical Review Letters",

issn = "0031-9007",

number = "5",

}

TY - JOUR

T1 - Observation of Light-by-Light Scattering in Ultraperipheral Pb+Pb Collisions with the ATLAS Detector

AU - ATLAS Collaboration

AU - Aad, G.

AU - Abbott, B.

AU - Abbott, D. C.

AU - Abdinov, O.

AU - Abed Abud, A.

AU - Abeling, K.

AU - Abhayasinghe, D. K.

AU - Abidi, S. H.

AU - Abouzeid, O. S.

AU - Abraham, N. L.

AU - Abramowicz, H.

AU - Abreu, H.

AU - Abulaiti, Y.

AU - Acharya, B. S.

AU - Achkar, B.

AU - Adachi, S.

AU - Adam, L.

AU - Adam Bourdarios, C.

AU - Adamczyk, L.

AU - Adamek, L.

AU - Adelman, J.

AU - Adersberger, M.

AU - Adiguzel, A.

AU - Adorni, S.

AU - Adye, T.

AU - Affolder, A. A.

AU - Afik, Y.

AU - Agapopoulou, C.

AU - Agaras, M. N.

AU - Aggarwal, A.

AU - Agheorghiesei, C.

AU - Aguilar-Saavedra, J. A.

AU - Ahmadov, F.

AU - Ahmed, W. S.

AU - Ai, X.

AU - Aielli, G.

AU - Akatsuka, S.

AU - Åkesson, T. P.A.

AU - Akilli, E.

AU - Akimov, A. V.

AU - Al Khoury, K.

AU - Alberghi, G. L.

AU - Albert, J.

AU - Arnold, H.

AU - Da Via, C.

AU - Dao, V.

AU - Hobbs, J.

AU - Jia, J.

AU - Piacquadio, G.

AU - Tsybychev, D.

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.

UR - https://www.scopus.com/pages/publications/85071896312

U2 - 10.1103/PhysRevLett.123.052001

DO - 10.1103/PhysRevLett.123.052001

M3 - Article

C2 - 31491300

AN - SCOPUS:85071896312

SN - 0031-9007

VL - 123

JO - Physical Review Letters

JF - Physical Review Letters

IS - 5

M1 - 052001

ER -

Observation of Light-by-Light Scattering in Ultraperipheral Pb+Pb Collisions with the ATLAS Detector

Abstract

Access to Document

Other files and links

Fingerprint

Cite this