Результаты исследований: Научные публикации в периодических изданиях › статья › Рецензирование
Evidence for light-by-light scattering and searches for axion-like particles in ultraperipheral PbPb collisions at sNN=5.02TeV. / The CMS collaboration ; Блинов, Владимир Евгеньевич; Сковпень, Юрий Иванович.
в: Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics, Том 797, 134826, 10.10.2019.Результаты исследований: Научные публикации в периодических изданиях › статья › Рецензирование
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TY - JOUR
T1 - Evidence for light-by-light scattering and searches for axion-like particles in ultraperipheral PbPb collisions at sNN=5.02TeV
AU - The CMS collaboration
AU - Sirunyan, A. M.
AU - Tumasyan, A.
AU - Adam, W.
AU - Ambrogi, F.
AU - Asilar, E.
AU - Bergauer, T.
AU - Brandstetter, J.
AU - Dragicevic, M.
AU - Erö, J.
AU - Escalante Del Valle, A.
AU - Flechl, M.
AU - Frühwirth, R.
AU - Ghete, V. M.
AU - Hrubec, J.
AU - Jeitler, M.
AU - Krammer, N.
AU - Krätschmer, I.
AU - Liko, D.
AU - Madlener, T.
AU - Mikulec, I.
AU - Rad, N.
AU - Rohringer, H.
AU - Schieck, J.
AU - Schöfbeck, R.
AU - Spanring, M.
AU - Spitzbart, D.
AU - Taurok, A.
AU - Waltenberger, W.
AU - Wittmann, J.
AU - Wulz, C. E.
AU - Zarucki, M.
AU - Chekhovsky, V.
AU - Mossolov, V.
AU - Suarez Gonzalez, J.
AU - De Wolf, E. A.
AU - Di Croce, D.
AU - Janssen, X.
AU - Lauwers, J.
AU - Pieters, M.
AU - Van Haevermaet, H.
AU - Van Mechelen, P.
AU - Van Remortel, N.
AU - Abu Zeid, S.
AU - Blekman, F.
AU - D'Hondt, J.
AU - De Bruyn, I.
AU - De Clercq, J.
AU - Barnyakov, A.
AU - Dimova, T.
AU - Kardapoltsev, L.
AU - Блинов, Владимир Евгеньевич
AU - Сковпень, Юрий Иванович
N1 - Publisher Copyright: © 2019 The Author(s)
PY - 2019/10/10
Y1 - 2019/10/10
N2 - Evidence for the light-by-light scattering process, γγ→γγ, in ultraperipheral PbPb collisions at a centre-of-mass energy per nucleon pair of 5.02TeV is reported. The analysis is conducted using a data sample corresponding to an integrated luminosity of 390μb−1 recorded by the CMS experiment at the LHC. Light-by-light scattering processes are selected in events with two photons exclusively produced, each with transverse energy ET γ>2GeV, pseudorapidity |ηγ|<2.4, diphoton invariant mass mγγ>5GeV, diphoton transverse momentum pT γγ<1GeV, and diphoton acoplanarity below 0.01. After all selection criteria are applied, 14 events are observed, compared to expectations of 9.0±0.9(theo) events for the signal and 4.0±1.2(stat) for the background processes. The excess observed in data relative to the background-only expectation corresponds to a significance of 3.7 standard deviations, and has properties consistent with those expected for the light-by-light scattering signal. The measured fiducial light-by-light scattering cross section, σfid(γγ→γγ)=120±46(stat)±28(syst)±12(theo)nb, is consistent with the standard model prediction. The mγγ distribution is used to set new exclusion limits on the production of pseudoscalar axion-like particles, via the (Figure presented.) process, in the mass range (Figure presented.).
AB - Evidence for the light-by-light scattering process, γγ→γγ, in ultraperipheral PbPb collisions at a centre-of-mass energy per nucleon pair of 5.02TeV is reported. The analysis is conducted using a data sample corresponding to an integrated luminosity of 390μb−1 recorded by the CMS experiment at the LHC. Light-by-light scattering processes are selected in events with two photons exclusively produced, each with transverse energy ET γ>2GeV, pseudorapidity |ηγ|<2.4, diphoton invariant mass mγγ>5GeV, diphoton transverse momentum pT γγ<1GeV, and diphoton acoplanarity below 0.01. After all selection criteria are applied, 14 events are observed, compared to expectations of 9.0±0.9(theo) events for the signal and 4.0±1.2(stat) for the background processes. The excess observed in data relative to the background-only expectation corresponds to a significance of 3.7 standard deviations, and has properties consistent with those expected for the light-by-light scattering signal. The measured fiducial light-by-light scattering cross section, σfid(γγ→γγ)=120±46(stat)±28(syst)±12(theo)nb, is consistent with the standard model prediction. The mγγ distribution is used to set new exclusion limits on the production of pseudoscalar axion-like particles, via the (Figure presented.) process, in the mass range (Figure presented.).
KW - CMS
KW - Light-by-light
KW - PbPb
KW - Photoproduction
KW - UPC
KW - PROTON-PROTON COLLISIONS
KW - EXCLUSIVE GAMMA-GAMMA
UR - http://www.scopus.com/inward/record.url?scp=85070721104&partnerID=8YFLogxK
U2 - 10.1016/j.physletb.2019.134826
DO - 10.1016/j.physletb.2019.134826
M3 - Article
AN - SCOPUS:85070721104
VL - 797
JO - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
JF - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
SN - 0370-2693
M1 - 134826
ER -
ID: 21237132