Triple parton scatterings in proton-nucleus collisions at high energies

Understand

A generic expression to compute triple parton scattering (TPS) cross sections in high-energy proton-nucleus (pA) collisions is derived as a function of the corresponding single-parton cross sections and an effective parameter encoding the transverse parton profile of the proton.

• The TPS cross sections are enhanced by a factor of $9\,A\approx 2000$ in pPb compared to those in proton-nucleon collisions at the same center-of-mass energy.
• Estimates for triple charm ($c\overline{c}$) and bottom ($b\overline{b}$) production in pPb collisions at LHC and FCC energies are presented based on next-to-next-to-leading order (NNLO) calculations for $c\overline{c}, b\overline{b}$ single-parton cross sections.
• At $\sqrt{s_{NN}} = 8.8$ TeV, about 10% of the pPb events have three $c\overline{c}$ pairs produced in separate partonic interactions.