Elliptic flow coefficients from transverse momentum conservation

Abstract: We calculate the $k$-particle ($k=2,4,6,8$) azimuthal cumulants resulting from the conservation of transverse momentum. We find that $c_2{k}>0$ and depending on the transverse momenta, $c_2{k}$ can reach substantial values even for a relatively large number of particles. The impact of our results on the understanding of the onset of collectivity in small systems is emphasized.