The spectra measurements of charged hadrons produced in the shower of a parton originating in the same hard scattering with a leptonically decaying Z boson arc reported in lead-lead nuclei (Pb-Pb) and proton-proton (pp) collisions at a nucleon-nucleon center-of-mass energy of 5.02 TeV. Both Pb-Pb and pp data sets are recorded by the CMS experiment at the LHC and correspond to an integrated luminosity of 1.7 nb(-1) and 320 pb(-1), respectively. Hadronic collision data with one reconstructed Z boson candidate with the transverse momentum p(T) > 30 GeV/c are analyzed. The Z boson constrains the initial energy and direction of the associated parton. In heavy ion events, azimuthal angular distributions of charged hadrons with respect to the direction of a Z boson are sensitive to modifications of the in-medium parton shower and medium response. compared to reference data from pp interactions, the results for central Pb-Pb collisions indicate a modification of the angular correlations. The measurements of the fragmentation functions and p(T) spectra of charged particles in Z boson events, which are sensitive to medium modifications of the parton shower longitudinal structure, are also reported. Significant modifications in central Pb-Pb events compared to the pp reference data are also found for these observables.

Using Z Boson Events to Study Parton-Medium Interactions in Pb-Pb Collisions

Vagnerini, A;Amapane, N;Argiro, S;Bellan, R;Bellora, A;Cappati, A;Costa, M;Covarelli, R;Kiani, B;Migliore, E;Monaco, V;Monteil, E;Obertino, M M;Pacher, L;Pinna Angioni, G L;Salvatico, R;Siviero, F;Sola, V;Solano, A;Soldi, D;Shchelina, K;Rumerio, P;Ravera, F;
2022-01-01

Abstract

The spectra measurements of charged hadrons produced in the shower of a parton originating in the same hard scattering with a leptonically decaying Z boson arc reported in lead-lead nuclei (Pb-Pb) and proton-proton (pp) collisions at a nucleon-nucleon center-of-mass energy of 5.02 TeV. Both Pb-Pb and pp data sets are recorded by the CMS experiment at the LHC and correspond to an integrated luminosity of 1.7 nb(-1) and 320 pb(-1), respectively. Hadronic collision data with one reconstructed Z boson candidate with the transverse momentum p(T) > 30 GeV/c are analyzed. The Z boson constrains the initial energy and direction of the associated parton. In heavy ion events, azimuthal angular distributions of charged hadrons with respect to the direction of a Z boson are sensitive to modifications of the in-medium parton shower and medium response. compared to reference data from pp interactions, the results for central Pb-Pb collisions indicate a modification of the angular correlations. The measurements of the fragmentation functions and p(T) spectra of charged particles in Z boson events, which are sensitive to medium modifications of the parton shower longitudinal structure, are also reported. Significant modifications in central Pb-Pb events compared to the pp reference data are also found for these observables.
2022
128
12
1
19
Sirunyan, A M; Tumasyan, A; Adam, W; Ambrogi, F; Bergauer, T; Dragicevic, M; Erö, J; Escalante Del Valle, A; Frühwirth, R; Jeitler, M; Krammer, N; Lec...espandi
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2318/1886324
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