# $\Upsilon$ Production in Heavy-Ion Collisions from the STAR Experiment

## TL;DR

This paper reports on measurements of $$ production in heavy-ion collisions from the STAR experiment, focusing on nuclear modification factors and yield ratios across different collision energies and systems.

## Contribution

It presents new measurements of $$ suppression and yield ratios in heavy-ion collisions, providing insights into quark-gluon plasma effects and comparing results across multiple experiments.

## Key findings

- Suppression of $(1S)$ observed in heavy-ion collisions.
- Yield ratios of $(2S+3S)$ to $(1S)$ are measured and compared.
- Results suggest sequential suppression of quarkonium states.

## Abstract

In these proceedings, we present recent results of $\Upsilon$ measurements in heavy-ion collisions from the STAR experiment at RHIC. Nuclear modification factors ($R_{AA}$) for $\Upsilon(1S)$ and $\Upsilon(1S+2S+3S)$ in U+U collisions at \sqrtsNN\ = 193 GeV are measured through the di-electron channel and compared to those in Au+Au collisions at \sqrtsNN\ = 200 GeV and Pb+Pb collisions at \sqrtsNN\ = 2.76 TeV. The ratio between the $\Upsilon(2S+3S)$ and $\Upsilon(1S)$ yields in Au+Au collisions at \sqrtsNN\ = 200 GeV is measured in the di-muon channel and compared to those in p+p collisions and in Pb+Pb collisions at \sqrtsNN\ = 2.76 TeV. Prospects for future $\Upsilon$ measurements with the STAR experiment are also discussed.