Parton ladder splitting and the rapidity dependence of transverse momentum spectra in deuteron-gold collisions at the BNL Relativistic Heavy Ion Collider

We present a phenomenological approach (EPOS), based on the parton model, but going much beyond by incorporating elastic and inelastic parton ladder splitting. Based on this model, we try to understand proton-proton and deuteron-gold ($d\mathrm{Au}$) collisions, in particular the rapidity dependence of transverse momentum results in $d\mathrm{Au}$ from all four experiments conducted on the BNL Relativistic Heavy Ion Collider.