We have collected transit times for the TRAPPIST-1 system with the Spitzer Space
Telescope over four years. We add to these ground-based, HST, and K2 transit-time …

We present a method for studying the secular gravitational dynamics of hierarchical multiple
systems consisting of nested binaries, which is valid for an arbitrary number of bodies and …

The discovery of 2012 VP113 initiated the debate on the origin of the Sedna family of
planetesimals in orbit around the Sun. Sednitos roam the outer regions of the Solar system …

We study the secular gravitational dynamics of quadruple systems consisting of a
hierarchical triple system orbited by a fourth body. These systems can be decomposed into …

Transiting circumbinary planets are more easily detected around short-period than long-
period binaries, but none have yet been observed by Kepler orbiting binaries with periods …

We extend the formalism of a previous paper to include the effects of flybys and
instantaneous perturbations such as supernovae on the long-term secular evolution of …

We study mass transfers between debris discs during stellar encounters. We carried out
numerical simulations of close flybys of two stars, one of which has a disc of planetesimals …

When fitting N-body models to astronomical data–such as transit times, radial velocity, and
astrometric positions at observed times–the derivatives of the model outputs with respect to …

We study analytically and experimentally certain symplectic and time-reversible N-body
integrators which employ a Kepler solver for each pair-wise interaction, including the …

We present a new symplectic integrator designed for collisional gravitational N-body
problems which makes use of Kepler solvers. The integrator is also reversible and …