A measurement of J/ψ and ψ(2S) production is presented. It is based on a data sample from Pb+Pb collisions at √sNN=5.02 TeV and pp collisions at s√=5.02 TeV recorded by the ATLAS detector at the LHC in 2015, corresponding to an integrated luminosity of 0.42 nb−1 and 25 pb−1 in Pb+Pb and pp, respectively. The measurements of per-event yields, nuclear modification factors, and non-prompt fractions are performed in the dimuon decay channel for 9<40 GeV in dimuon transverse momentum, and −2<2 in rapidity. Strong suppression is found in Pb+Pb collisions for both prompt and non-prompt J/ψ, increasing with event centrality. The suppression of prompt ψ(2S) is observed to be stronger than that of J/ψ, while the suppression of non-prompt ψ(2S) is equal to that of the non-prompt J/ψ within uncertainties, consistent with the expectation that both arise from b-quarks propagating through the medium. Despite prompt and non-prompt J/ψ arising from different mechanisms, the dependence of their nuclear modification factors on centrality is found to be quite similar.
Prompt and non-prompt J/ψ and ψ(2S) suppression at high transverse momentum in 5.02 TeV Pb+Pb collisions with the ATLAS experiment / De Castro , S. ; Fabbri , L. ; Gabrielli , A. ; Rinaldi , L. ; Semprini Cesari , N. ; Sioli , M. ; Villa , M. ; Zoccoli , A. ; Bellagamba , L. ; Boscherini , D. ; Bruni , A. ; Bruni , G. ; D’Amen , G. ; Giacobbe , B. ; Polini , A. ; Sbarra , C. ; Sidoti , A. ; Spighi , R. ; Franchini , M. ; Mengarelli , A. ; Romano , M. ; Valentinetti , S. ; Alberghi , G. L. ; Biondi , S. ; Fabbri , F. ; Lasagni Manghi , F; Massa , L. ; Ucchielli , G. ; Vittori , C. ; ATLAS collaboration. - In: THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS. - ISSN 1434-6044. - STAMPA. - 78:9(2018), pp. 762.1-762.28. [10.1140/epjc/s10052-018-6219-9]
Prompt and non-prompt J/ψ and ψ(2S) suppression at high transverse momentum in 5.02 TeV Pb+Pb collisions with the ATLAS experiment
De Castro , S.;Fabbri , L.;Gabrielli , A.;Rinaldi , L.;Semprini Cesari , N.;Sioli , M.;Villa , M.;Zoccoli , A.;Bellagamba , L.;Boscherini , D.;Bruni , A.;D’Amen , G.;Giacobbe , B.;Polini , A.;Sbarra , C.;Spighi , R.;Franchini , M.;Mengarelli , A.;Romano , M.;Valentinetti , S.;Alberghi , G. L.;Biondi , S.;Fabbri , F.;Lasagni Manghi , F;Massa , L.;Ucchielli , G.;Vittori , C.;
2018
Abstract
A measurement of J/ψ and ψ(2S) production is presented. It is based on a data sample from Pb+Pb collisions at √sNN=5.02 TeV and pp collisions at s√=5.02 TeV recorded by the ATLAS detector at the LHC in 2015, corresponding to an integrated luminosity of 0.42 nb−1 and 25 pb−1 in Pb+Pb and pp, respectively. The measurements of per-event yields, nuclear modification factors, and non-prompt fractions are performed in the dimuon decay channel for 9<40 GeV in dimuon transverse momentum, and −2<2 in rapidity. Strong suppression is found in Pb+Pb collisions for both prompt and non-prompt J/ψ, increasing with event centrality. The suppression of prompt ψ(2S) is observed to be stronger than that of J/ψ, while the suppression of non-prompt ψ(2S) is equal to that of the non-prompt J/ψ within uncertainties, consistent with the expectation that both arise from b-quarks propagating through the medium. Despite prompt and non-prompt J/ψ arising from different mechanisms, the dependence of their nuclear modification factors on centrality is found to be quite similar.File | Dimensione | Formato | |
---|---|---|---|
10.1140_epjc_s10052-018-6219-9.pdf
accesso aperto
Tipo:
Versione (PDF) editoriale
Licenza:
Licenza per Accesso Aperto. Creative Commons Attribuzione (CCBY)
Dimensione
1.82 MB
Formato
Adobe PDF
|
1.82 MB | Adobe PDF | Visualizza/Apri |
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.