Upsilon production in U plus U collisions at root s(NN)=193 GeV measured with the STAR experiment

We present a measurement of the inclusive production of. mesons in U + U collisions at root s(NN) = 193 GeV at midrapidity (vertical bar y vertical bar < 1). Previous studies in central Au+Au collisions at root s(NN) = 200 GeV show a suppression of Upsilon (1S+2S+3S) production relative to expectations from the Upsilon yield in p+p collisions scaled by the number of binary nucleon-nucleon collisions (N-coll), with an indication that the.(1S) state is also suppressed. The present measurement extends the number of participant nucleons in the collision (N-part) by 20% compared to Au+Au collisions, and allows us to study a system with higher energy density. We observe a suppression in both the Upsilon (1S+2S+3S) and Upsilon (1S) yields in central U+U data, which consolidates and extends the previously observed suppression trend in Au+Au collisions.