Collectivity from interference

Understand

In hadronic collisions, interference between different production channels affects momentum distributions of multi-particle final states.

• As this QCD interference does not depend on the strong coupling constant, it is part of the no-interaction baseline that needs to be controlled prior to searching for other manifestations of collective dynamics.
• Here, we introduce a model that is based on the QCD theory of multi-parton interactions and that allows one to study interference effects in the production of $m$ particles in hadronic collisions with $N$ parton-parton interactions ("sources").
• In an expansion in powers of $1/(N_c^2-1)$ and to leading order in the number of sources $N$, we calculate interference effects in the $m$-particle spectra and we determine from them the second and fourth order cumulant momentum anisotropies $v_n$.