Constraining $\Delta G$ at low-x with Double Longitudinal Spin Asymmetries for Forward Hadrons in PHENIX

Currently, global fits of the gluon polarization $\Delta g(x)$ are constrained by PHENIX and STAR data from polarized p+p collisions at RHIC in the range $0.03< x <0.3$. These fits yield a first moment of the gluon polarization, $\Delta G$, consistent with zero, but they are not sensitive to possible contributions to $\Delta G$ from the low-x region. By measuring $A_{LL}$ for forward ($3.1<\eta<3.9$) $\pi^{0}$ production in the Muon Piston Calorimeter (MPC) at PHENIX, we aim to probe the structure of $\Delta g(x)$ in this low-x region. Production of hadrons at large pseudo-rapidities is favored in asymmetric collisions between a high-x quark and a low-x gluon that give the center of momentum frame a large forward boost. Simulations using the event generator PYTHIA have shown that measuring forward $\pi^{0}$'s can access $\Delta g(x)$ for $x \sim$ $10^{-3}$. Here, we present the analysis status of $A_{LL}$ for merged $\pi^{0}$'s in the MPC at $\sqrt{s}=500\: GeV$ from the 2009 dataset. This data along with data from polarized p+p runs at PHENIX through 2015 will help to provide stronger constraints on the form of $\Delta g(x)$ for ongoing global analyses.