Speaker
Description
SpinQuest is the Fermilab's high-luminosity Drell-Yan experiment that aims to explore the interaction of 120 GeV proton beam with transversely polarized ammonia (NH$_3$), and deuterated ammonia (ND$_3$) targets to probe the Sivers functions of light quark flavors in the nucleon sea. A non-vanishing sea quark Sivers functions provide evidence of their orbital angular momentum, which would contribute to resolve the nucleon spin puzzle. The experiment will also measure the $J/\psi$ azimuthal asymmetries, which are sensitive to the gluon Sivers function. Such studies are performed using a polarized target assembly deploying a split-pair 5 T superconducting magnet and a powerful cooling system based on the $^4$He evaporation refrigerator. The latter operates at 1 K through high-powered evaporation facilitated by a roots stack with a pumping rate of $\approx~$17,000 liters per hour. With such a setup, the expected average target polarization of $\approx$ 80\% (32\%) for NH$_3$ (ND$_3$) will be achieved based on the dynamic nuclear polarization technique. In this talk, an overview of the first run-period performance of the SpinQuest polarized targets will be presented alongside the ongoing efforts to study systematic effects of the $J/\psi$ Transverse Single Spin Asymmetry.
This work is supported in part by the U.S. DOE award $\#$: DE-FG02-07ER41528.
