Search Publications
UNIVERSEMACHINE: The correlation between galaxy growth and dark matter halo assembly from z = 0-10
Conroy, Charlie; Behroozi, Peter; Wechsler, Risa H. +1 more
We present a method to flexibly and self-consistently determine individual galaxies' star formation rates (SFRs) from their host haloes' potential well depths, assembly histories, and redshifts. The method is constrained by galaxies' observed stellar mass functions, SFRs (specific and cosmic), quenched fractions, ultraviolet (UV) luminosity functi…
SIMBA: Cosmological simulations with black hole growth and feedback
Davé, Romeel; Narayanan, Desika; Li, Qi +3 more
We introduce the SIMBA simulations, the next generation of the MUFASA cosmological galaxy formation simulations run with GIZMO's meshless finite mass hydrodynamics. SIMBA includes updates to MUFASA's sub-resolution star formation and feedback prescriptions, and introduces black hole growth via the torque-limited accretion model of Anglés-Alcázar e…
Evidence for two early accretion events that built the Milky Way stellar halo
Myeong, G. C.; Evans, N. W.; Belokurov, V. +2 more
The Gaia Sausage is the major accretion event that built the stellar halo of the Milky Way galaxy. Here, we provide dynamical and chemical evidence for a second substantial accretion episode, distinct from the Gaia Sausage. The Sequoia Event provided the bulk of the high-energy retrograde stars in the stellar halo, as well as the recently discover…
Mean proper motions, space orbits, and velocity dispersion profiles of Galactic globular clusters derived from Gaia DR2 data
Hilker, M.; Bellini, A.; Baumgardt, H. +1 more
We have derived the mean proper motions and space velocities of 154 Galactic globular clusters and the velocity dispersion profiles of 141 globular clusters based on a combination of Gaia DR2 proper motions with ground-based line-of-sight velocities. Combining the velocity dispersion profiles derived here with new measurements of the internal mass…
A Gaia Data Release 2 catalogue of white dwarfs and a comparison with SDSS
Toonen, Silvia; Hollands, Mark; Raddi, Roberto +11 more
We present a catalogue of white dwarf candidates selected from the second data release of Gaia (DR2). We used a sample of spectroscopically confirmed white dwarfs from the Sloan Digital Sky Survey (SDSS) to map the entire space spanned by these objects in the Gaia Hertzsprung-Russell diagram. We then defined a set of cuts in absolute magnitude, co…
The formation and assembly history of the Milky Way revealed by its globular cluster population
Kruijssen, J. M. Diederik; Crain, Robert A.; Bastian, Nate +2 more
We use the age-metallicity distribution of 96 Galactic globular clusters (GCs) to infer the formation and assembly history of the Milky Way (MW), culminating in the reconstruction of its merger tree. Based on a quantitative comparison of the Galactic GC population to the 25 cosmological zoom-in simulations of MW-mass galaxies in the E-MOSAICS proj…
H0LiCOW - IX. Cosmographic analysis of the doubly imaged quasar SDSS 1206+4332 and a new measurement of the Hubble constant
Treu, T.; Fassnacht, C. D.; Meylan, G. +15 more
We present a blind time-delay strong lensing (TDSL) cosmographic analysis of the doubly imaged quasar SDSS 1206+4332 . We combine the relative time delay between the quasar images, Hubble Space Telescope imaging, the Keck stellar velocity dispersion of the lensing galaxy, and wide-field photometric and spectroscopic data of the field to constrain …
Vertical waves in the solar neighbourhood in Gaia DR2
Bovy, Jo; Bennett, Morgan
The vertical structure and dynamics of stars in our local Galactic neighbourhood contains much information about the local distribution of visible and dark matter and of perturbations to the Milky Way disc. We use data on the positions and velocities of stars in the solar neighbourhood from Gaia Data Release 2 (DR2) and large spectroscopic surveys…
The total mass of the Large Magellanic Cloud from its perturbation on the Orphan stream
Li, T. S.; Evans, N. W.; Belokurov, V. +14 more
In a companion paper by Koposov et al., RR Lyrae from Gaia Data Release 2 are used to demonstrate that stars in the Orphan stream have velocity vectors significantly misaligned with the stream track, suggesting that it has received a large gravitational perturbation from a satellite of the Milky Way. We argue that such a mismatch cannot arise due …
The origin of accreted stellar halo populations in the Milky Way using APOGEE, Gaia, and the EAGLE simulations
Bovy, Jo; Majewski, Steven R.; Holtzman, Jon +12 more
Recent work indicates that the nearby Galactic halo is dominated by the debris from a major accretion event. We confirm that result from an analysis of APOGEE-DR14 element abundances and Gaia-DR2 kinematics of halo stars. We show that ∼2/3 of nearby halo stars have high orbital eccentricities (e ≳ 0.8), and abundance patterns typical of massive Mi…