Measurement of elliptic flow of light nuclei at root s(NN)=200, 62.4, 39, 27, 19.6, 11.5, and 7.7 GeV at the BNL Relativistic Heavy Ion Collider

Abstract

We present measurements of second-order azimuthal anisotropy (v(2)) at midrapidity (vertical bar y vertical bar < 1.0) for light nuclei d, t, He-3 (for root s(NN) = 200, 62.4, 39, 27, 19.6, 11.5, and 7.7 GeV) and antinuclei <(d)over bar> (root s(NN) = 200, 62.4, 39, 27, and 19.6 GeV) and (3)(He) over bar (root s(NN) = 200 GeV) in the STAR (Solenoidal Tracker at RHIC) experiment. The v(2) for these light nuclei produced in heavy-ion collisions is compared with those for p and (p) over bar. We observe mass ordering in nuclei v(2)(p(T)) at low transverse momenta (p(T) < 2.0 GeV/c). We also find a centrality dependence of v(2) for d and <(d)over bar>. The magnitude of v(2) for t and He-3 agree within statistical errors. Light-nuclei v(2) are compared with predictions from a blast-wave model. Atomic mass number (A) scaling of light-nuclei v(2)(p(T)) seems to hold for p(T)/A < 1.5 GeV/c. Results on light-nuclei v(2) from a transport-plus-coalescence model are consistent with the experimental measurements.