  We consider the production of $W$ and $Z / \gamma^{*}$ gauge bosons in
proton-proton collisions at a center-of-mass energy of $\sqrt{s} = 510
\mbox{GeV}$ available at RHIC at BNL, operating at high luminosity. We stress
the importance of measuring the transverse double-spin asymmetries $A_{TT}$, in
connection with available transversely polarized beams with a high degree of
polarisation. We will discuss some theoretical issues related to the predicted
asymmetries. These studies are contrasted to the 2017 RHIC running operation of
transversely polarized beams of mid-rapidity $W$ and $Z$ boson production at a
center-of-mass energy of $\sqrt{s}=510\,$GeV along with long-term prospects
beyond 2020 at RHIC.
