Skip to main content
eScholarship
Open Access Publications from the University of California

Study of hard double-parton scattering in four-jet events in pp collisions at √s=7 TeV with the ATLAS experiment

  • Author(s): Aaboud, M
  • Aad, G
  • Abbott, B
  • Abdallah, J
  • Abdinov, O
  • Abeloos, B
  • Aben, R
  • AbouZeid, OS
  • Abraham, NL
  • Abramowicz, H
  • Abreu, H
  • Abreu, R
  • Abulaiti, Y
  • Acharya, BS
  • Adachi, S
  • Adamczyk, L
  • Adams, DL
  • Adelman, J
  • Adomeit, S
  • Adye, T
  • Affolder, AA
  • Agatonovic-Jovin, T
  • Aguilar-Saavedra, JA
  • Ahlen, SP
  • Ahmadov, F
  • Aielli, G
  • Akerstedt, H
  • Åkesson, TPA
  • Akimov, AV
  • Alberghi, GL
  • Albert, J
  • Albrand, S
  • Alconada Verzini, MJ
  • Aleksa, M
  • Aleksandrov, IN
  • Alexa, C
  • Alexander, G
  • Alexopoulos, T
  • Alhroob, M
  • Ali, B
  • Aliev, M
  • Alimonti, G
  • Alison, J
  • Alkire, SP
  • Allbrooke, BMM
  • Allen, BW
  • Allport, PP
  • Aloisio, A
  • Alonso, A
  • Alonso, F
  • Alpigiani, C
  • Alshehri, AA
  • Alstaty, M
  • Alvarez Gonzalez, B
  • Álvarez Piqueras, D
  • Alviggi, MG
  • Amadio, BT
  • Amako, K
  • Amaral Coutinho, Y
  • Amelung, C
  • Amidei, D
  • Amor Dos Santos, SP
  • Amorim, A
  • Amoroso, S
  • Amundsen, G
  • Anastopoulos, C
  • Ancu, LS
  • Andari, N
  • Andeen, T
  • Anders, CF
  • Anders, G
  • Anders, JK
  • Anderson, KJ
  • Andreazza, A
  • Andrei, V
  • Angelidakis, S
  • Angelozzi, I
  • Angerami, A
  • Anghinolfi, F
  • Anisenkov, AV
  • Anjos, N
  • Annovi, A
  • Antel, C
  • Antonelli, M
  • et al.
Abstract

© 2016, The Author(s). Inclusive four-jet events produced in proton-proton collisions at a centre-of-mass energy of s=7 TeV are analysed for the presence of hard double-parton scattering using data corresponding to an integrated luminosity of 37.3 pb−1, collected with the ATLAS detector at the LHC. The contribution of hard double-parton scattering to the production of four-jet events is extracted using an artificial neural network, assuming that hard double-parton scattering can be approximated by an uncorrelated overlaying of dijet events. For events containing at least four jets with transverse momentum pT≥ 20 GeV and pseudorapidity |η| ≤ 4.4, and at least one having pT≥ 42.5 GeV, the contribution of hard double-parton scattering is estimated to be fDPS= 0.092− 0.011+ 0.005(stat.)− 0.037+ 0.033(syst.). After combining this measurement with those of the inclusive dijet and four-jet cross-sections in the appropriate phase space regions, the effective cross-section, σeff, was determined to be σeff= 14. 9− 1.0+ 1.2(stat.)− 3.8+ 5.1(syst.) mb. This result is consistent within the quoted uncertainties with previous measurements of σeff, performed at centre-of-mass energies between 63 GeV and 8 TeV using various final states, and it corresponds to 21− 6+ 7% of the total inelastic cross-section measured at s=7 TeV. The distributions of the observables sensitive to the contribution of hard double-parton scattering, corrected for detector effects, are also provided.[Figure not available: see fulltext.]

Main Content
Current View