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Recent results in d+Au and p+Pb collisions at RHIC and the LHC provide evidence for collective expansion and flow of the created medium. We propose a control set of experiments to directly compare particle emission patterns from p+Pb, d+Au, and ^{3}He+Au or t+Au collisions at the same sqrt[s_{NN}] . Using a Monte Carlo Glauber simulation we find that a ^{3}He or triton projectile, with a realistic wave function description, induces a significant intrinsic triangular shape to the initial medium. If the system lives long enough, this survives into a significant third-order flow moment v_{3} even with viscous damping. By comparing systems with one, two, and three initial hot spots, one could disentangle the effects from the initial spatial distribution of the deposited energy and viscous damping. These are key tools for answering the question of how small a droplet of matter is necessary to form a quark-gluon plasma described by nearly inviscid hydrodynamics.

A. Adare, 13 S. Afanasiev, 31 C. Aidala, 40, 44, 45

Measurements of midrapidity charged particle multiplicity distributions, dN ch /dη, and midrapidity transverse-energy distributions, dET /dη, are presented for a variety of collision systems and energies. Included are distributions for Au+Au collisions at For all A+A collisions down to √ s N N = 7.7 GeV, it is observed that the midrapidity data are better described by scaling withNqp than scaling with Npart. Also presented are estimates of the Bjorken energy density, εBJ, and the ratio of dET /dη to dN ch /dη, the latter of which is seen to be constant as a function of centrality for all systems.