Azimuthal Harmonics in Small and Large Collision Systems at RHIC Top
PHYSICAL REVIEW LETTERS 122 (17) 172301
The first (v(1)(fluc)), second (v(2)), and third (v(3)) harmonic coefficients of the azimuthal particle distribution at midrapidity are extracted for charged hadrons and studied as a function of transverse momentum (P-T) and mean charged particle multiplicity density < N-ch > in U + U (root s(NN) = 193 GeV), Au + Au, Cu + Au, Cu + Cu, d + Au, and p + Au collisions at, root s(NN) = 200 GeV with the STAR detector. For the same < N-ch >, the v(1)(fluc) and v(3) coefficients are observed to be independent of the collision system, while v(2) exhibits such a scaling only when normalized by the initial-state eccentricity (epsilon(2)). The data also show that ln(v(2)/epsilon(2)) scales linearly with < N-ch >(-1/3). These measurements provide insight into initial-geometry fluctuations and the role of viscous hydrodynamic attenuation on v(n) from small to large collision systems.
Cite article as:
L. Adamczyk, R. Lednický, . et al., "Azimuthal Harmonics in Small and Large Collision Systems at RHIC Top", PHYSICAL REVIEW LETTERS 122 (17) 172301 (2019)