Understanding Eccentricity and Precession I: How well can we measure them?*

The presence or absence of eccentricity and precession can be signatures of different formation channels for binary coalescences. Our ability to measure precession and eccentricity accurately and to distinguish between the two is essential for inferring the origin of gravitational wave (GW) signals. To this end, we present a two-part study on the distinguishability and measurability of these two key parameters. In this talk, we simulate eccentric-only and precessing-only signals with a state-of-the-art GW model across multiple masses and distances. We then analyze each signal with the same model in two secenarios: (1) assuming only eccentric, non-precessing systems and (2) assuming only quasi-circular, precessing systems. Finally, we assess our ability to measure both parameters as well as our inabiltiy to distinguish between the two.