Study of Jet Quenching with Z+jet Correlations in Pb-Pb and pp Collisions at s NN=5.02 TeV

Date Issued
23-08-2017
Author(s)
Sirunyan, A. M.
Tumasyan, A.
Adam, W.
Asilar, E.
Bergauer, T.
Brandstetter, J.
Brondolin, E.
Dragicevic, M.
Erö, J.
Flechl, M.
Friedl, M.
Frühwirth, R.
Ghete, V. M.
Hartl, C.
Hörmann, N.
Hrubec, J.
Jeitler, M.
König, A.
Krätschmer, I.
Liko, D.
Matsushita, T.
Mikulec, I.
Rabady, D.
Rad, N.
Rahbaran, B.
Rohringer, H.
Schieck, J.
Strauss, J.
Waltenberger, W.
Wulz, C. E.
Chekhovsky, V.
Dvornikov, O.
Dydyshka, Y.
Emeliantchik, I.
Litomin, A.
Makarenko, V.
Mossolov, V.
Stefanovitch, R.
Suarez Gonzalez, J.
Zykunov, V.
Shumeiko, N.
Alderweireldt, S.
De Wolf, E. A.
Janssen, X.
Lauwers, J.
Van De Klundert, M.
Van Haevermaet, H.
Van Mechelen, P.
Van Remortel, N.
Van Spilbeeck, A.
Abu Zeid, S.
Blekman, F.
D'Hondt, J.
Daci, N.
De Bruyn, I.
Deroover, K.
Lowette, S.
Moortgat, S.
Moreels, L.
Olbrechts, A.
Python, Q.
Skovpen, K.
Tavernier, S.
Van Doninck, W.
Van Mulders, P.
Van Parijs, I.
Brun, H.
Clerbaux, B.
De Lentdecker, G.
Delannoy, H.
Fasanella, G.
Favart, L.
Goldouzian, R.
Grebenyuk, A.
Karapostoli, G.
Lenzi, T.
Léonard, A.
Luetic, J.
Maerschalk, T.
Marinov, A.
Randle-Conde, A.
Seva, T.
Vander Velde, C.
Vanlaer, P.
Vannerom, D.
Yonamine, R.
Zenoni, F.
Zhang, F.
Cimmino, A.
Cornelis, T.
Dobur, D.
Fagot, A.
Gul, M.
Khvastunov, I.
Poyraz, D.
Salva, S.
Schöfbeck, R.
Tytgat, M.
Van Driessche, W.
Yazgan, E.
DOI
Abstract
The production of jets in association with Z bosons, reconstructed via the μ+μ- and e+e- decay channels, is studied in pp and, for the first time, in Pb-Pb collisions. Both data samples were collected by the CMS experiment at the LHC, at a nucleon-nucleon center-of-mass energy of 5.02 TeV. The Pb-Pb collisions were analyzed in the 0%-30% centrality range. The back-to-back azimuthal alignment was studied in both pp and Pb-Pb collisions for Z bosons with transverse momentum pTZ>60 GeV/c and a recoiling jet with pTjet>30 GeV/c. The pT imbalance xjZ=pTjet/pTZ, as well as the average number of jet partners per Z, RjZ, was studied in intervals of pTZ. The RjZ is found to be smaller in Pb-Pb than in pp collisions, which suggests that in Pb-Pb collisions a larger fraction of partons associated with the Z bosons fall below the 30 GeV/c pTjet threshold because they lose energy.
Volume
119