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Related papers: The Splash without a merger

200 papers

We use numerical simulations to examine the structure of merger remnants resulting from collisions of gas-rich spiral galaxies. When the gas fraction of the progenitors is small, the remnants structurally and kinematically resemble…

Astrophysics · Physics 2009-11-10 Volker Springel , Lars Hernquist

Circa 10 billion years ago the Milky Way merged with a massive satellite, Gaia-Enceladus. To gain insight into the properties of its debris we analyse in detail the suite of simulations from Villalobos & Helmi (2008), which includes an…

Astrophysics of Galaxies · Physics 2020-10-28 Helmer H. Koppelman , Roy O. Y. Bos , Amina Helmi

Accreted stars in the Milky Way (MW) preserve information about the progenitor galaxies where they formed in their chemical and kinematic properties. In this study, we use the chemo-dynamical signatures in the merger debris to approximate…

Astrophysics of Galaxies · Physics 2026-03-16 Andrea Sante , Andreea S. Font , Daisuke Kawata , T. Lucas Makinen , Robert J. J. Grand

Our Galaxy is thought to have undergone an active evolutionary history dominated by star formation, the accretion of cold gas, and, in particular, mergers up to 10 gigayear ago. The stellar halo reveals rich fossil evidence of these…

The formation and structure of the Milky Way has a fundamental role in our understanding of the universe and its evolution, and thanks to the Gaia mission and large spectroscopic surveys, we live an exceptional moment of data availability,…

Astrophysics of Galaxies · Physics 2024-05-08 Elvis Cantelli , Ramachrisna Teixeira

We present chemodynamical simulations of a Milky Way-type galaxy using a self-consistent hydrodynamical code that includes supernova feedback and chemical enrichment, and predict the spatial distribution of elements from Oxygen to Zinc. In…

Astrophysics of Galaxies · Physics 2015-05-20 Chiaki Kobayashi , Naohito Nakasato

Evidence suggests that the Milky Way (MW) underwent a major collision with the Gaia-Sausage/Enceladus (GSE) dwarf galaxy around cosmic noon. While GSE has since been fully disrupted, it brought in ex situ stars and dynamically heated in…

Astrophysics of Galaxies · Physics 2025-08-28 Deokkeun An , Young Sun Lee , Yutaka Hirai , Timothy C. Beers

We use a series of high-resolution N-body simulations of a `Milky-Way' halo, coupled to semi-analytic techniques, to study the formation of our own Galaxy and of its stellar halo. Our model Milky Way galaxy is a relatively young system…

Astrophysics · Physics 2015-05-13 Gabriella De Lucia , Amina Helmi

Using the ARTEMIS set of 45 high-resolution cosmological simulations, we investigate a range of merger-induced dynamical transformations of Milky Way-like galaxies. We first identify populations of accreted stars on highly radial orbits,…

Astrophysics of Galaxies · Physics 2022-08-11 Adam M. Dillamore , Vasily Belokurov , Andreea S. Font , Ian G. McCarthy

The standard cosmological model ($\Lambda$-CDM) predicts that galaxies are built through hierarchical assembly on cosmological timescales$^{1,2}$. The Milky Way, like other disc galaxies, underwent violent mergers and accretion of small…

Cosmological hydrodynamical simulations as well as observations indicate that spiral galaxies are comprised of five different components: dark matter halo, stellar disc, stellar bulge, gaseous disc and gaseous halo. While the first four…

Astrophysics of Galaxies · Physics 2015-05-27 Benjamin P. Moster , Andrea V. Maccio' , Rachel S. Somerville , Thorsten Naab , Thomas J. Cox

It is now generally believed that galaxies were built up through gravitational amplification of primordial fluctuations and the subsequent merging of smaller precursor structures. The stars of the structures that assembled to form the Milky…

Astrophysics · Physics 2012-08-27 Amina Helmi , Simon D. M. White , P. Tim de Zeeuw , and HongSheng Zhao

The Milky Way's (MW) inner stellar halo contains an [Fe/H]-rich component with highly eccentric orbits, often referred to as the "last major merger." Hypotheses for the origin of this component include Gaia-Sausage/Enceladus (GSE), where…

Astrophysics of Galaxies · Physics 2024-05-09 Thomas Donlon , Heidi Jo Newberg , Robyn Sanderson , Emily Bregou , Danny Horta , Arpit Arora , Nondh Panithanpaisal

The elemental abundance distribution of stars encodes the history of the gas-phase abundance in the Milky Way. Without a large, unbiased sample of highly precise stellar ages, the exact timing and nature of this history must be inferred…

Astrophysics of Galaxies · Physics 2025-02-26 Angus Beane

We continue our series of papers on phase-space distributions of stars in the Milky Way based on photometrically derived metallicities and Gaia astrometry, with a focus on the halo-disk interface in the local volume. To exploit various…

Astrophysics of Galaxies · Physics 2023-07-26 Deokkeun An , Timothy C. Beers , Young Sun Lee , Thomas Masseron

Recent dynamical analysis based on Gaia data have revealed major accretion events in Milky Way's history. Nevertheless, our understanding of the primordial Galaxy is hindered because the bona fide identification of the most metal-poor and…

Compact binary mergers involving at least one neutron star are promising sites for the synthesis of $\textit{r}$-process elements found in stars and planets. However, mergers can take place at significant offsets from their host galaxies,…

Astrophysics of Galaxies · Physics 2022-11-09 Benjamin Amend , Jonathan Zrake , Dieter H. Hartmann

Using three-dimensional cosmological simulations, we study the assembly process of one of the first galaxies, with a total mass of 10^8 M_sun, collapsing at z = 10. Our main goal is to trace the transport of the heavy chemical elements…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Thomas H. Greif , Simon C. O. Glover , Volker Bromm , Ralf S. Klessen

Recent studies show that the Milky Way stellar halo is composed of populations of different origins, shaped by multiple accretion events. To better understand the formation of the Milky Way and other spiral galaxies, we characterize the…

A scenario for the formation of the bi-modality in the chemical space [$\alpha$/Fe] vs [Fe/H] of the Milky Way was recently proposed in which $\alpha$-enhanced stars are produced early and quickly in clumps. Besides accelerating the…

Astrophysics of Galaxies · Physics 2020-02-12 Leandro Beraldo e Silva , Victor P. Debattista , Tigran Khachaturyants , David Nidever