Measurement of inclusive J/$ψ$ pair production cross section in pp collisions at $\sqrt{s} = 13$ TeV

The production cross section of inclusive J/$\psi$ pairs in pp collisions at a centre-of-mass energy $\sqrt{s} = 13$ TeV is measured with ALICE. The measurement is performed for J/$\psi$ in the rapidity interval $2.5 <~ y <~ 4.0$ and for transverse momentum $p_{\rm T} > 0$. The production cross section of inclusive J/$\psi$ pairs is reported to be $10.3 \pm 2.3 {\rm (stat.)} \pm 1.3 {\rm (syst.)}$ nb in this kinematic interval. The contribution from non-prompt J/$\psi$ (i.e. originated from beauty-hadron decays) to the inclusive sample is evaluated. The results are discussed and compared with data.


Submitted to: PRC
e-Print: arXiv:2303.13431 | PDF | inSPIRE
Figure group

Figure 1

Projections of a fit to the 2-dimensional invariant mass distribution for inclusive J/$\psi$ pair candidates for (left) $m_1(\mu_1^+ \mu_1^-)$ and (right) $m_2(\mu_2^+ \mu_2^-)$. The (black) markers show data. The (black) solid line represents the total fit function. The (blue and green) dashed-dotted lines indicate the background contribution from a combination of a real J/$\psi$ signal with a combinatorial candidate. The (yellow) dotted line represents muon pairs from combinatorial background.