Measurements of Four-Lepton Production at the Z Resonance in pp Collisions at root s=7 and 8 TeV with ATLAS
Makaleler > Tam Makale · 2014
Yazarlar: G. Aad, B. Abbott, J. Abdallah, S. Abdel Khalek, O. Abdinov, R. Aben, B. Abi, M. Abolins, O. S. AbouZeid, H. Abramowicz, Rena ÇİFTÇİ, R. Abreu, Y. Abulaiti, B. S. Acharya, L. Adamczyk, D. L. Adams, J. Adelman, S. Adomeit, T. Adye, T. Agatonovic-Jovin, J. A. Aguilar-Saavedra, M. Agustoni, S. P. Ahlen, A. Ahmad, F. Ahmadov, G. Aielli, H. Akerstedt, T. P. A. Akesson, G. Akimoto, A. V. Akimov, G. L. Alberghi, J. Albert, S. Albrand, M. J. Alconada Verzini, M. Aleksa, I. N. Aleksandrov, C. Alexa, G. Alexander, G. Alexandre, T. Alexopoulos, M. Alhroob, G. Alimonti, L. Alio, J. Alison, B. M. M. Allbrooke, L. J. Allison, P. P. Allport, S. E. Allwood-Spiers, J. Almond, A. Aloisio, A. Alonso, F. Alonso, C. Alpigiani, A. Altheimer, B. Alvarez Gonzalez, M. G. Alviggi, K. Amako, Y. Amaral Coutinho, C. Amelung, D. Amidei, S. P. Amor Dos Santos, A. Amorim, S. Amoroso, N. Amram, G. Amundsen, C. Anastopoulos, L. S. Ancu, N. Andari, T. Andeen, C. F. Anders, G. Anders, K. J. Anderson, A. Andreazza, V. Andrei, X. S. Anduaga, S. Angelidakis, I. Angelozzi, P. Anger, A. Angerami, F. Anghinolfi, A. V. Anisenkov, N. Anjos, A. Annovi, A. Antonaki, M. Antonelli, A. Antonov, J. Antos, F. Anulli, M. Aoki, L. Aperio Bella, R. Apolle, G. Arabidze, I. Aracena, Y. Arai, J. P. Araque, A. T. H. Arce, J-F. Arguin, S. Argyropoulos, M. Arik, A. J. Armbruster, V. Arnal, K. Augsten, M. Aurousseau, A. Bangert, D. Benchekroun, A. Bogouch, W. K. Brooks, T. Buanes, V. Cindro, T. Djobava, S. Franz, H. Hakobyan, M. Losada
PHYSICAL REVIEW LETTERS, SCI Expanded İndekslerine Giren Dergi, Uluslararası, 2014, cilt 112
DOI: 10.1103/physrevlett.112.231806
Özet
Measurements of four-lepton (4l, l = e,mu) production cross sections at the Z resonance in pp collisions at the LHC with the ATLAS detector are presented. For dilepton and four-lepton invariant mass regions m (l+l)- > 5 GeV and 80 < m(4l) < 100 GeV, the measured cross sections are 76 +/- 18(stat) +/- 4(syst) +/- 1.4(lumi) fb and 107 +/- 9(stat) +/- 4(syst) +/- 3.0(lumi) fb at root s=7 and 8 TeV, respectively. By subtracting the nonresonant 4l production contributions and normalizing with Z -> mu(+)mu(-) events, the branching fraction for the Z boson decay to 4l is determined to be (3.20 +/- 0.25(stat) +/- 0.13(syst)) x10(-6), consistent with the standard model prediction.