TY - JOUR
T1 - Search for new phenomena in events with at least three photons collected in $pp$ collisions at $\sqrt{s}$ = 8 TeV with the ATLAS detector
AU - ATLAS Collaboration
AU - Newman, Paul
AU - Aperio Bella, Ludovica
AU - Baca, Matthew
AU - Bansil, Hardeep
AU - Bracinik, Juraj
AU - Charlton, David
AU - Chisholm, Andrew
AU - Daniells, Andrew
AU - Hawkes, Christopher
AU - Head, Simon
AU - Hillier, Stephen
AU - Levy, Mark
AU - Mudd, Richard
AU - Murillo Quijada, Javier
AU - Nikolopoulos, Konstantinos
AU - Owen, Rhys
AU - Slater, Mark
AU - Thomas, Jurgen
AU - Thompson, Paul
AU - Watson, Alan
AU - Watson, Miriam
AU - Wilson, John
N1 - 20 pages plus author list + cover pages (37 pages total), 5 figures, 5 tables, submitted to EPJC; all figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/EXOT-2013-24/
PY - 2015/9/16
Y1 - 2015/9/16
N2 - Results of a search for new phenomena in events with at least three photons are reported. Data from proton--proton collisions at a centre-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 20.3 fb$^{-1}$, were collected with the ATLAS detector at the LHC. The observed data are well described by the Standard Model. Limits at the 95% confidence level on new phenomena are presented based on the rate of events in an inclusive signal region and a restricted signal region targeting the rare decay $Z\to 3\gamma$, as well as di-photon and tri-photon resonance searches. For a Standard Model Higgs boson decaying to four photons via a pair of intermediate pseudoscalar particles ($a$), limits are found to be $\sigma \times {\text {BR}}(h \rightarrow aa) \times {\text {BR}}(a \rightarrow \gamma \gamma)^{2} $ $ 125 GeV, and for a $Z'$ decaying to three photons via $Z' \rightarrow a+\gamma \rightarrow 3\gamma$. Additionally, the observed limit on the branching ratio of the $Z$ boson decay to three photons is found to be BR$(Z \rightarrow 3\gamma)
AB - Results of a search for new phenomena in events with at least three photons are reported. Data from proton--proton collisions at a centre-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 20.3 fb$^{-1}$, were collected with the ATLAS detector at the LHC. The observed data are well described by the Standard Model. Limits at the 95% confidence level on new phenomena are presented based on the rate of events in an inclusive signal region and a restricted signal region targeting the rare decay $Z\to 3\gamma$, as well as di-photon and tri-photon resonance searches. For a Standard Model Higgs boson decaying to four photons via a pair of intermediate pseudoscalar particles ($a$), limits are found to be $\sigma \times {\text {BR}}(h \rightarrow aa) \times {\text {BR}}(a \rightarrow \gamma \gamma)^{2} $ $ 125 GeV, and for a $Z'$ decaying to three photons via $Z' \rightarrow a+\gamma \rightarrow 3\gamma$. Additionally, the observed limit on the branching ratio of the $Z$ boson decay to three photons is found to be BR$(Z \rightarrow 3\gamma)
KW - hep-ex
U2 - 10.1140/epjc/s10052-016-4034-8
DO - 10.1140/epjc/s10052-016-4034-8
M3 - Article
SN - 1434-6044
JO - European Physical Journal C
JF - European Physical Journal C
ER -