380 citations · 1.6k across the 13 of their papers we have counts for
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The stellar mass distribution of the Milky Way's bar: an analytic model
Mattia C. Sormani, Ortwin Gerhard, Matthieu Portail +2
We present an analytic model of the stellar mass distribution of the Milky Way bar. The model is obtained by fitting a multi-component parametric density distribution to a made-to-…
Sculpting Andromeda -- made-to-measure models for M31's bar and composite bulge: dynamics, stellar and dark matter mass
Matias Blaña, Ortwin Gerhard, Christopher Wegg +6
The Andromeda galaxy (M31) contains a box/peanut bulge (BPB) entangled with a classical bulge (CB) requiring a triaxial modelling to determine the dynamics, stellar and dark matter…
The Initial Mass Function of the Inner Galaxy Measured From OGLE-III Microlensing Timescales
Christopher Wegg, Ortwin Gerhard, Matthieu Portail
We use the timescale distribution of ~3000 microlensing events measured by the OGLE-III survey, together with accurate new made-to-measure dynamical models of the Galactic bulge/ba…
Chemodynamical Modelling of the Galactic Bulge and Bar
Matthieu Portail, Christopher Wegg, Ortwin Gerhard +1
We present the first self-consistent chemodynamical model fitted to reproduce data for the galactic bulge, bar and inner disk. We extend the Made-to-Measure method to an augmented…
Revisiting the Tale of Hercules: how stars orbiting the Lagrange points visit the Sun
Angeles Pérez-Villegas, Matthieu Portail, Christopher Wegg +1
We propose a novel explanation for the Hercules stream consistent with recent measurements of the extent and pattern speed of the Galactic bar. We have adapted a made-to-measure dy…
Andromeda chained to the Box -- Dynamical Models for M31: Bulge & Bar
Matias Blana, Christopher Wegg, Ortwin Gerhard +5
Andromeda is our nearest neighbouring disk galaxy and a prime target for detailed modelling of the evolutionary processes that shape galaxies. We analyse the nature of M31's triaxi…
The Stellar Halo in the Inner Milky Way: Predicted Shape and Kinematics
Angeles Pérez-Villegas, Matthieu Portail, Ortwin Gerhard
We have used N-body simulations for the Milky Way to investigate the kinematic and structural properties of the old metal-poor stellar halo in the barred inner region of the Galaxy…
Dynamical modelling of the Galactic bulge and bar: the Milky Way's bar pattern speed, stellar, and dark matter mass distribution
Matthieu Portail, Ortwin Gerhard, Christopher Wegg +1
We construct a large set of dynamical models of the galactic bulge, bar and inner disk using the Made-to-Measure method. Our models are constrained to match the red clump giant den…
MOA-II Galactic Microlensing Constraints: The Inner Milky Way has a Low Dark Matter Fraction and a Near Maximal Disk
Christopher Wegg, Ortwin Gerhard, Matthieu Portail
Microlensing provides a unique tool to break the stellar to dark matter degeneracy in the inner Milky Way. We combine N-body dynamical models fitted to the Milky Way's Boxy/Peanut…
Gas dynamics in the Milky Way: a low pattern speed model
Zhi Li, Ortwin Gerhard, Juntai Shen +2
We present gas flow models for the Milky Way based on high-resolution grid-based hydrodynamical simulations. The basic galactic potential we use is from a N-body model constrained…
The Structure of the Milky Way's Bar Outside the Bulge
Christopher Wegg, Ortwin Gerhard, Matthieu Portail
While it is incontrovertible that the inner Galaxy contains a bar, its structure near the Galactic plane has remained uncertain, where extinction from intervening dust is greatest.…
Peanuts, brezels and bananas: food for thought on the orbital structure of the Galactic bulge
M. Portail, C. Wegg, O. Gerhard
Recent observations have discovered the presence of a Box/Peanut or X-shape structure in the Galactic bulge. Such Box/Peanut structures are common in external disc galaxies, and ar…
Made-to-Measure models of the Galactic Box/Peanut bulge: stellar and total mass in the bulge region
M. Portail, C. Wegg, O. Gerhard +1
We construct dynamical models of the Milky Way's Box/Peanut (B/P) bulge, using the recently measured 3D density of Red Clump Giants (RCGs) as well as kinematic data from the BRAVA…