Rapidity Dependent Pion Spectra from Fixed-Target Au$+$Al Collisions at STAR

By analyzing collisions between beam halo nuclei and the beam pipe, the STAR detector at RHIC can study fixed-target Au$+$Al collisions. As such, 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 details of the fixed-target acceptance and efficiency of the STAR detector. In addition, we present the fixed-target pion spectra as a function of rapidity from the three Au$+$Al datasets at center-of-mass energies of 4.5, 3.5, and 3.0 GeV.