47 citations · 172 across the 19 of their papers we have counts for
19 papers
Using Machine Learning to Model Stellar Collisions in our Galactic Center
Tristan C. Sand, Sanaea C. Rose, Elena González Prieto +8
Direct collisions in the inner pc of the Galactic center can alter the orbits and properties of stars. The outcome of a collision depends on a number of parameters, including the m…
Aerosols and hydrocarbons in the atmosphere of a white dwarf planet
Ryan J. MacDonald, Christopher E. O'Connor, Victoria A. Boehm +15
Most stars, including our Sun, will one day evolve into red giants and, subsequently, white dwarfs. Several planet candidates have recently been identified orbiting white dwarfs, d…
Red vs. Blue: How metallicity shapes black hole dynamics and mergers in dense star clusters
Saloni Agrawal, Kyle Kremer, Michael Zevin +6
Dense star clusters are a well-established environment for the formation of gravitational wave sources through dynamical interactions. Recent LIGO-Virgo-KAGRA (LVK) events such as…
Getting Tilted: Random Walk of Binary Black Hole Spin-Orbit Alignment in Dense Star Clusters
Maia A. S. Martinez, Christopher E. O'Connor, Fulya Kıroğlu +1
It is commonly assumed that the spin-orbit angles of binary black holes (BBHs) originating from dense stellar environments rapidly converge to an isotropic distribution following a…
Black hole mergers from dense star clusters with realistic binary populations
Christopher E. O'Connor, Kyle Kremer, Saloni Agrawal +5
We present a suite of 24 full-lifetime simulations of dense star clusters with the Cluster Monte Carlo (CMC) code, featuring updated input physics and a realistic distribution of i…
An analytical approach to binary populations in globular clusters
Christopher E. O'Connor, Kyle Kremer, Frederic A. Rasio
Globular clusters (GCs) display much lower binary fractions than found among main-sequence stars in the solar neighborhood. The physical cause of this difference is debatable: does…
Machine Learning Methods for Stellar Collisions. I. Predicting Outcomes of SPH Simulations
Elena González Prieto, James C. Lombardi, Sanaea C. Rose +7
Stellar collisions can occur frequently in dense cluster environments, and play a crucial role in producing exotic phenomena from blue stragglers in globular clusters to high-energ…
Intruder Alert: Breaking Resonant Chains with Planetesimal Flybys
Jiaru Li, Christopher E. O'Connor, Frederic A. Rasio
The orbital architectures of compact exoplanet systems record their complicated dynamical histories. Recent research supports the ``breaking-the-chains'' hypothesis, which proposes…
The fate of Gaia's wide binaries: Interplay of white-dwarf recoil and tidal capture
Christopher E. O'Connor
White dwarfs (WDs) receive natal velocity boosts of due to recoil from asymmetric mass loss during the late asymptotic giant branch (AGB) stage. I…
Thermal Emission and Confirmation of the Frigid White Dwarf Exoplanet WD 1856+534b
Mary Anne Limbach, Andrew Vanderburg, Ryan J. MacDonald +12
We report the detection of thermal emission from and confirm the planetary nature of WD 1856+534b, the first transiting planet known to orbit a white dwarf star. Observations with…
Metal pollution in Sun-like stars from destruction of ultra-short-period planets
Christopher E. O'Connor, Dong Lai
Chemical evidence indicates that an appreciable fraction of Sun-like stars have engulfed rocky planets during their main-sequence lifetimes. We investigate whether the tidal evolut…
Emerging Researchers in Exoplanetary Science (ERES): Lessons Learned in Conference Organization for Early-Career Researchers
W. Garrett Levine, Konstantin Gerbig, Emma M. Louden +5
Since 2015, the Emerging Researchers in Exoplanetary Science (ERES) conference has provided a venue for early-career researchers in exoplanetary astronomy, astrophysics, and planet…
On the pollution of white dwarfs by exo-Oort cloud comets
Christopher E. O'Connor, Dong Lai, Darryl Z. Seligman
A large fraction of white dwarfs (WDs) have metal-polluted atmospheres, which are produced by accreting material from remnant planetary systems. The composition of the accreted deb…
Giant planet engulfment by evolved giant stars: light curves, asteroseismology, and survivability
Christopher E. O'Connor, Lars Bildsten, Matteo Cantiello +1
About ten percent of Sun-like (-) stars will engulf a - planet as they expand during the red giant branch (RGB) or asymptotic giant branch (AGB) phas…
Secular chaos in white-dwarf planetary systems: origins of metal pollution and short-period planetary companions
Christopher E. O'Connor, Jean Teyssandier, Dong Lai
Secular oscillations in multi-planet systems can drive chaotic evolution of a small inner body through non-linear resonant perturbations. This "secular chaos" readily pushes the in…
Gemini/GMOS Transmission Spectroscopy of the Grazing Planet Candidate WD 1856+534 b
Siyi Xu, Hannah Diamond-Lowe, Ryan J. MacDonald +12
WD 1856+534 b is a Jupiter-sized, cool giant planet candidate transiting the white dwarf WD 1856+534. Here, we report an optical transmission spectrum of WD 1856+534 b obtained fro…
Enhanced Lidov-Kozai migration and the formation of the transiting giant planet WD1856+534b
Christopher E. O'Connor, Bin Liu, Dong Lai
We investigate the possible origin of the transiting giant planet WD1856+534b, the first strong exoplanet candidate orbiting a white dwarf, through high-eccentricity migration (HEM…
High-eccentricity migration of planetesimals around polluted white dwarfs
Christopher E. O'Connor, Dong Lai
Several white dwarfs with atmospheric metal pollution have been found to host small planetary bodies (planetesimals) orbiting near the tidal disruption radius. We study the physica…
Constraining Planetary Migration and Tidal Dissipation with Coeval Hot Jupiters
Christopher E. O'Connor, Bradley M. S. Hansen
We investigate the constraints on the formation of, and tidal dissipation processes in, hot Jupiters (HJs) that can be inferred based on reliable knowledge of the age of a system o…