Rapidity Dependent Pion Spectra from Fixed-Target $\sqrt{s_{NN}} =$ 3.0, 3.5, and 4.5 GeV Au$+$Al Collisions at STAR

The STAR detector at RHIC can study fixed-target Au$+$Al collisions resulting from the beam halo interacting with the beam pipe. Utilizing these data, STAR can extend the reach of the beam energy scan to lower center-of-mass energies and higher baryon chemical potentials than previously considered. This allows for a more thorough search for the possible onset of deconfinement of the phase transition between hadronic and partonic matter. In this talk, we discuss analysis details including the fixed-target acceptance and efficiency of the STAR detector. In addition we will present rapidity dependent fixed-target pion spectra from each of three Au$+$Al datasets at center-of-mass energies of 4.5, 3.5, and 3.0 GeV.