During stores, the beam-beam interaction has a significant impact on the beam and luminosity lifetimes in RHIC. This was observed in heavy ion, and even more pronounced in proton collisions. Observations include measurements of beam-beam induced tune shifts, lifetime and emittance growth measurements with and without beam-beam interaction, and background rates as a function of tunes. In addition, RHIC is currently the only hadron collider in which strong-strong beam-beam effects can be seen. Coherent beam-beam modes were observed, and suppressed by tune changes. In this article we summarize the most important beam-beam observations made during stores so far.
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