Quarkonium in a weakly‐coupled quark‐gluon plasma

We report about a recent calculation of the heavy quarkonium mass and decay width in a quark‐gluon plasma, whose temperature T and screening mass $mD$ satisfy the hierarchy $mαs⋙T⋙mαs2⋙mD,$ m being the heavy‐quark mass, up to order $mαs5.$ The calculation may be relevant to understand the behavior of the Υ(1S) in a quark‐gluon plasma at present‐day colliders.