Procedure of $V_{2,J/\psi-tracklet}$ extraction from $V_{2,dimuon-tracklet}(m_{\mu\mu})$

Scope: PWG
PWG-DQ (Dileptons and Quarkonia)
13 TeV
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Figure Caption

Procedure of $V_{2,J/\psi-tracklet}$ extraction from $V_{2,dimuon-tracklet}(m_{\mu\mu})$

Detail description

Procedure of $V_{2,J/\psi-tracklet}$ extraction from $V_{2,dimuon-tracklet}(m_{\mu\mu})$


Data points are obtained following the procedure detailed in the AN and the p-Pb analysis (Phys. Lett. B 780 (2018) 7-20)

The non-flow suppression is done through yield subtraction


The high-multiplicity yields and low-multiplicity yields have been computed prior to this plot. In the pT bin between 3 and 4 GeV/c (for the purpose of this figure), yield subtraction has been made and the $V_{2}$ of the subtracted yields has been computed in each mass bin.

The obtained points form the top plot: $V_{2}{dimuon-tracklet}(m_{\mu\mu})$

The signal $J/\psi$ contribution is separated from the background dimuon by fitting the invariant mass (seen on the bottom plot) and then fitting $V_{2}{dimuon-tracklet}(m_{\mu\mu})$ with the contribution to $V_{2}$ from signal $J/\psi$ and with the contribution from background dimuon (following a seconde order polynomial)

The obtained value of $V_{2}{J/\psi-tracklet}$ in this $p_T$ bin is compatible with 0.


Central class: 0-5%

Peripheral class: 40-100%

Centrality estimator: V0M


Data sample: Run2 pp (2016 to 2018 included)


Event cuts:

N_contrib > 0

Usual PU rejection + Multiplicity dependant PU rejection

σ_(Z_(vtx, SPD) )< 0.25 cm (if SPD Vertexer)

Z_vtx |<10 cm

η_SPD within SPD acceptance

ΔΦ_tracklets<10 mrad (azimuth difference between inner and outer SPD layers) – standard


(Di)Muon selection:

R_abs  in [17.6, 89.5]

Match a trigger track  with p_T  >0.5 GeV

pDCA < 6σ

η_muon  in acceptance

Dimuon charge = 0

y_dimu  in acceptance

p_T_dimu  in [0;12]  GeV/c