Stern, E.G. Ainsworth, R. Amundson, J.F. Lu, Q. JACoW Geneva, Switzerland 978-3-95450-180-9 10.18429/JACoW-NAPAC2016-THPOA18 English 1135-1137 THPOA18 ion simulation space-charge collective-effects wakefield Contribution to a conference proceedings 2017 2017-01 http://dx.doi.org/10.18429/JACoW-NAPAC2016-THPOA18 https://jacow.org/napac2016/papers/thpoa18.pdf The Recycler is an 8 GeV/c proton storage ring at Fermilab. To achieve the 700 MW beam power goals for the NOvA neutrino oscillation experiment, the Recycler accumulates 12 batches of 80-bunch trains from the Booster using slip-stacking. One set of bunch trains are injected into the ring and decelerated, then a second set is injected at the nominal momentum. The trains slip past each other longitudinally due to their momenta difference. We have recently extended the multi-bunch portion of the Synergia beam simulation program to allow co-propagation of bunch trains at different momenta. In doing so, we have expanded the applicability of the massively parallel multi-bunch physics portion of Synergia to include new categories of bunch-bunch interactions. We present results from our first application of these capabilities to batch-on-batch slip stacking in the Recycler.