Longitudinal Double-Spin Asymmetries for Dijet Production at Intermediate Pseudorapidity in Polarized Proton-Proton Collisions at $\sqrt{s}$ = 510 GeV

The analysis of dijets produced in polarized $pp$ collisions at the Relativistic Heavy Ion Collider (RHIC) provides information on the gluon helicity contribution to the spin of the proton. Because quark-gluon and gluon-gluon scattering processes dominate jet production in $pp$ collisions at RHIC energies of $\sqrt{s}$ = 200 GeV and $\sqrt{s}$ = 510 GeV, the longitudinal double-spin asymmetry $A_{LL}$ for dijet production is sensitive to the polarized gluon distribution function $\Delta g(x)$. Dijet measurements at larger pseudorapidity and higher center-of-mass energy probe lower values of partonic momentum fraction $x$, a region where $\Delta g(x)$ is still poorly constrained. Previous measurements of dijet $A_{LL}$ at the Solenoidal Tracker at RHIC (STAR) have been carried out at either mid-rapidity or $\sqrt{s}$ = 200 GeV, or both. We present the status of the first analysis of $A_{LL}$ for dijets with at least one jet reconstructed at intermediate pseudorapidity (0.8 $< \eta <$ 2.0) in polarized $pp$ collisions at $\sqrt{s}$ = 510 GeV, based on data taken during the 2012 and 2013 RHIC running periods.