Outputs (84)

Origin of Mars’s moons by disruptive partial capture of an asteroid (2024)
Journal Article
Kegerreis, J. A., Lissauer, J. J., Eke, V. R., Sandnes, T. D., & Elphic, R. C. (2025). Origin of Mars’s moons by disruptive partial capture of an asteroid. Icarus, 425, Article 116337. https://doi.org/10.1016/j.icarus.2024.116337

The origin of Mars’s small moons, Phobos and Deimos, remains unknown. They are typically thought either to be captured asteroids or to have accreted from a debris disk produced by a giant impact. Here, we present an alternative scenario wherein fragm... Read More about Origin of Mars’s moons by disruptive partial capture of an asteroid.

A Recent Impact Origin of Saturn’s Rings and Mid-sized Moons (2023)
Journal Article
Teodoro, L. F. A., Kegerreis, J. A., Estrada, P. R., Ćuk, M., Eke, V. R., Cuzzi, J. N., Massey, R. J., & Sandnes, T. D. (2023). A Recent Impact Origin of Saturn’s Rings and Mid-sized Moons. Astrophysical Journal, 955(2), Article 137. https://doi.org/10.3847/1538-4357/acf4ed

We simulate the collision of precursor icy moons analogous to Dione and Rhea as a possible origin for Saturn's remarkably young rings. Such an event could have been triggered a few hundred million years ago by resonant instabilities in a previous sat... Read More about A Recent Impact Origin of Saturn’s Rings and Mid-sized Moons.

Dealing with density discontinuities in planetary SPH simulations (2022)
Journal Article
Ruiz-Bonilla, S., Borrow, J., Eke, V., Kegerreis, J., Massey, R., Sandnes, T., & Teodoro, L. (2022). Dealing with density discontinuities in planetary SPH simulations. Monthly Notices of the Royal Astronomical Society, 512(3), 4660-4668. https://doi.org/10.1093/mnras/stac857

Density discontinuities cannot be precisely modelled in standard formulations of smoothed particles hydrodynamics (SPH) because the density field is defined smoothly as a kernel-weighted sum of neighbouring particle masses. This is a problem when per... Read More about Dealing with density discontinuities in planetary SPH simulations.

Measurement of the free neutron lifetime using the neutron spectrometer on NASA's Lunar Prospector mission (2021)
Journal Article
Wilson, J. T., Lawrence, D. J., Peplowski, P. N., Eke, V. R., & Kegerreis, J. A. (2021). Measurement of the free neutron lifetime using the neutron spectrometer on NASA's Lunar Prospector mission. Physical Review C, 104(4), Article 045501. https://doi.org/10.1103/physrevc.104.045501

We use data from the Lunar Prospector Neutron Spectrometer to make the second space-based measurement of the free neutron lifetime finding τ n = 887 ± 14 stat + 7 − 3 syst s, which is within 1 σ of the accepted value. This measurement expands the ran... Read More about Measurement of the free neutron lifetime using the neutron spectrometer on NASA's Lunar Prospector mission.

The surprising accuracy of isothermal Jeans modelling of self-interacting dark matter density profiles (2020)
Journal Article
Robertson, A., Massey, R., Eke, V., Schaye, J., & Theuns, T. (2021). The surprising accuracy of isothermal Jeans modelling of self-interacting dark matter density profiles. Monthly Notices of the Royal Astronomical Society, 501(3), 4610-5634. https://doi.org/10.1093/mnras/staa3954

Recent claims of observational evidence for self-interacting dark matter (SIDM) have relied on a semi-analytic method for predicting the density profiles of galaxies and galaxy clusters containing SIDM. We present a thorough description of this metho... Read More about The surprising accuracy of isothermal Jeans modelling of self-interacting dark matter density profiles.

The effect of pre-impact spin on the Moon-forming collision (2020)
Journal Article
Ruiz-Bonilla, S., Eke, V., Kegerreis, J., Massey, R., & Teodoro, L. (2021). The effect of pre-impact spin on the Moon-forming collision. Monthly Notices of the Royal Astronomical Society, 500(3), 2861-2870. https://doi.org/10.1093/mnras/staa3385

We simulate the hypothesized collision between the proto-Earth and a Mars-sized impactor that created the Moon. Among the resulting debris disc in some impacts, we find a self-gravitating clump of material. It is roughly the mass of the Moon, contain... Read More about The effect of pre-impact spin on the Moon-forming collision.

Atmospheric Erosion by Giant Impacts onto Terrestrial Planets: A Scaling Law for any Speed, Angle, Mass, and Density (2020)
Journal Article
Kegerreis, J., Eke, V., Catling, D., Massey, R., Teodoro, L., & Zahnle, K. (2020). Atmospheric Erosion by Giant Impacts onto Terrestrial Planets: A Scaling Law for any Speed, Angle, Mass, and Density. Astrophysical Journal Letters, 901(2), Article L31. https://doi.org/10.3847/2041-8213/abb5fb

We present a new scaling law to predict the loss of atmosphere from planetary collisions for any speed, angle, impactor mass, target mass, and body composition, in the regime of giant impacts onto broadly terrestrial planets with relatively thin atmo... Read More about Atmospheric Erosion by Giant Impacts onto Terrestrial Planets: A Scaling Law for any Speed, Angle, Mass, and Density.

Atmospheric Erosion by Giant Impacts onto Terrestrial Planets (2020)
Journal Article
Kegerreis, J., Eke, V., Massey, R., & Teodoro, L. (2020). Atmospheric Erosion by Giant Impacts onto Terrestrial Planets. Astrophysical Journal, 897(2), Article 161. https://doi.org/10.3847/1538-4357/ab9810

We examine the mechanisms by which the atmosphere can be eroded by giant impacts onto Earth-like planets with thin atmospheres, using 3D smoothed particle hydrodynamics simulations with sufficient resolution to directly model the fate of low-mass atm... Read More about Atmospheric Erosion by Giant Impacts onto Terrestrial Planets.

Space-based measurement of the neutron lifetime using data from the neutron spectrometer on NASA's MESSENGER mission (2020)
Journal Article
Wilson, J. T., Lawrence, D. J., Peplowski, P. N., Eke, V. R., & Kegerreis, J. A. (2020). Space-based measurement of the neutron lifetime using data from the neutron spectrometer on NASA's MESSENGER mission. Physical Review Research, 2(2), Article 023316. https://doi.org/10.1103/physrevresearch.2.023316

We establish the feasibility of measuring the neutron lifetime via an alternative, space-based class of methods, which use neutrons generated by galactic cosmic ray spallation of planets surfaces and atmospheres. Free neutrons decay via the weak inte... Read More about Space-based measurement of the neutron lifetime using data from the neutron spectrometer on NASA's MESSENGER mission.

Understanding the large inferred Einstein radii of observed low-mass galaxy clusters (2020)
Journal Article
Robertson, A., Massey, R., & Eke, V. (2020). Understanding the large inferred Einstein radii of observed low-mass galaxy clusters. Monthly Notices of the Royal Astronomical Society, 494(4), 4706-4712. https://doi.org/10.1093/mnras/staa1076

We assess a claim that observed galaxy clusters with mass ∼1014M⊙ are more centrally concentrated than predicted in lambda cold dark matter (ΛCDM). We generate mock strong gravitational lensing observations, taking the lenses from a cosmological hydr... Read More about Understanding the large inferred Einstein radii of observed low-mass galaxy clusters.