57 citations · 157 across the 13 of their papers we have counts for
13 papers
Alignment of the Milky Way and M31 with their cosmic environment. New insights from constrained Local Group simulations
Hanneke C. Woudenberg, Amina Helmi, Ewoud Wempe +4
The large-scale environment is thought to play an important role in setting galaxy properties. The Milky Way (MW) and Andromeda (M31) reside in the Local Group, embedded in the Loc…
Evidence of a massive accretion event 1.8 billion years before the Gaia-Sausage-Enceladus merger
Davide Massari, Chiara Zerbinati, Cristiano Fanelli +15
The merger history of the Galaxy has been traced back firmly to redshift 2 (10 Billion years ago). While evidence for the existence of at least one more significant merger before t…
Group Accretion in Milky Way-like Stellar Haloes
Thomas M. Callingham, Amina Helmi
As galaxies form hierarchically, larger satellites may accrete alongside smaller companions in group infall events. This coordinated accretion is likely to have left signatures in…
Chronology of our Galaxy from Gaia colour-magnitude diagram fitting (ChronoGal) II. Unveiling the formation and evolution of the kinematically selected Thick and Thin Discs
Emma Fernández-Alvar, Tomás Ruiz-Lara, Carme Gallart +16
Understanding the formation and evolution of the Milky Way's thin and thick discs is crucial to galaxy formation studies. We derive age and metallicity distributions of the kinemat…
Chronology of our Galaxy from Gaia colour-magnitude diagram fitting (ChronoGal) -- III. Age and metallicity distribution of Gaia-Sausage-Enceladus stars near the Sun
Yllari K. González-Koda, Tomás Ruiz-Lara, Carme Gallart +14
Context. Gaia-Sausage-Enceladus is considered the last major merger that contributed to the formation of the Milky Way. Its remnants dominate the nearby accreted stellar halo of th…
Unevolved Li-rich stars at low metallicity: a possible formation pathway through novae
Tadafumi Matsuno, Alex Kemp, Ataru Tanikawa +7
A small fraction of low-mass stars have been found to have anomalously high Li abundances. Although it has been suggested that mixing during the red giant branch phase can lead to…
Characterisation of local halo building blocks: Thamnos and Sequoia
Emma Dodd, Tomás Ruiz-Lara, Amina Helmi +5
A crucial aspect of galaxy evolution is the pace at which galaxies build up their mass. We investigate this hierarchical assembly by uncovering and timing accretion events experien…
Testing MOND using the dynamics of nearby stellar streams
Orlin Koop, Amina Helmi
The stellar halo of the Milky Way is built up, at least in part, from debris from past mergers. Stars from such merger events define substructures in phase-space, for example in th…
Constrained cosmological simulations of the Local Group using Bayesian hierarchical field-level inference
Ewoud Wempe, Guilhem Lavaux, Simon D. M. White +3
We present a novel approach based on Bayesian field-level inference capable of resolving individual galaxies within the Local Group (LG), enabling detailed studies of its structure…
On the Galactic rotation curve inferred from the Jeans equations Assessing its robustness using Gaia DR3 and cosmological simulations
Orlin Koop, Teresa Antoja, Amina Helmi +2
Several works have recently applied Jeans modelling to Gaia-based datasets to infer the circular velocity curve for the Milky Way. Such works have consistently found evidence for a…
Filling in the Blanks: A Method to Infer the Substructure Membership and Dynamics of 5D Stars
Thomas M. Callingham, Amina Helmi
We present and test a method to infer a probability density function (PDF) for the missing vlos of a star with 5D information within kpc. We use stars from the Gaia DR3 RVS c…
Chronology of our Galaxy from Gaia Colour-Magnitude Diagram-fitting (ChronoGal). I. The formation and evolution of the thin disk from the Gaia Catalogue of Nearby Stars
C. Gallart, F. Surot, S. Cassisi +15
The current major challenge to reconstruct the chronology of the Milky Way (MW) is the difficulty to derive precise stellar ages. CMD-fitting offers an alternative to individual ag…
Full 5D characterisation of the Sagittarius stream with Gaia DR2 RR Lyrae
P. Ramos, C. Mateu, T. Antoja +4
The Sagittarius stream is one of the best tools that we currently have to estimate the mass and shape of our Galaxy. However, assigning membership and obtaining the phase-space dis…