English
Related papers

Related papers: A Semi-analytic Model of Halo Dynamics

200 papers

We review Galactic halo formation theories and supporting evidence, in particular kinematics and detailed chemical abundances of stars in some relevant globular clusters as well as Local Group dwarf galaxies. Outer halo red HB clusters tend…

Astrophysics · Physics 2009-11-13 Doug Geisler , George Wallerstein , Verne V. Smith , Dana I. Casetti-Dinescu

In a semi-numerical model of reionization, the evolution of ionization fraction is simulated approximately by the ionizing photon to baryon ratio criterion. In this paper we incorporate a semi-analytical model of galaxy formation based on…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Jie Zhou , Qi Guo , Gaochao Liu , Bin Yue , Yidong Xu , Xuelei Chen

We investigate the progenitors of low-inclination retrograde substructures in the Milky Way (MW) halo, which are remnants of accreted dwarf galaxies on retrograde orbits. Our sample consists of halo stars with low orbital inclinations and…

Astrophysics of Galaxies · Physics 2026-04-16 Young Kwang Kim , Young Sun Lee , Timothy C. Beers

We present a new cosmological galaxy formation model, $\nu^2$GC, as an updated version of our previous model $\nu$GC. We adopt the so-called "semi-analytic" approach, in which the formation history of dark matter halos is computed by ${\it…

It is established that there exists a direct link between the formation history of star cluster populations and their host galaxies. However, our lack of understanding of the assembly of star cluster populations impede our ability to use…

We present a detailed comparison between numerical cosmological hydrodynamic zoom simulations and semi-analytic models (SAMs) run within merger trees extracted from the simulations. The high-resolution simulations represent 48 individual…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 M. Hirschmann , T. Naab , R. Somerville , A. Burkert , L. Oser

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

Dwarf galaxies are known to have remarkably low star formation efficiency due to strong feedback. Adopting the dwarf galaxies of the Milky Way as a laboratory, we explore a flexible semi-analytic galaxy formation model to understand how the…

We examine the evolution of assembly bias using a semi-analytical model of galaxy formation implemented in the Millennium-WMAP7 N-body simulation. We consider fixed number density galaxy samples ranked by stellar mass or star formation…

Astrophysics of Galaxies · Physics 2019-02-15 Sergio Contreras , Idit Zehavi , Nelson Padilla , Carlton Baugh , Esteban Jiménez , Ivan Lacerna

Recent studies emphasize that an empirical relation between the stellar mass of galaxies and the mass of their host dark matter subhaloes can predict the clustering of galaxies and its evolution with cosmic time. In this paper we study the…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-07 Eyal Neistein , Simone M. Weinmann , Cheng Li , Michael Boylan-Kolchin

As galaxy simulations increase in resolution more attention is being paid towards the evolution of dwarf galaxies and how the simulations compare to observations. Despite this increasing resolution we are however, far away from resolving…

Astrophysics of Galaxies · Physics 2015-09-30 Matthew Nichols , Yves Revaz , Pascale Jablonka

Recent observational and theoretical studies of the Local Group (LG) dwarf galaxies have highlighted their unique star-formation history, stellar metallicity, gas content, and kinematics. We investigate the commonality of these features by…

(Abridged) The hierarchical formation scenario for the stellar halo requires the accretion and disruption of dwarf galaxies, yet low-metallicity halo stars are enriched in alpha-elements compared to similar, low-metallicity stars in dwarf…

According to the hierarchical scenario, galaxies form via merging and accretion of small objects. Using N-body simulations, we study the frequency of merging events in the history of the halos. We find that at z<~2 the merging rate of the…

Astrophysics · Physics 2009-10-31 Stefan Gottloeber , Anatoly Klypin , Andrey Kravtsov

We use semi-analytical modelling of galaxy formation to study the redshift evolution of the galaxy merger fractions and merger ratesin Lambda CDM and quintessence (QCDM) cosmologies, their dependence on physical parameters as the…

Astrophysics · Physics 2009-11-06 S. Khochfar , A. Burkert

In L\"ovdal et al, we presented a data-driven method for clustering in Integrals of Motion space and applied it to a large sample of nearby halo stars with 6D phase-space information. We identified a large number of clusters, many of which…

Astrophysics of Galaxies · Physics 2022-09-14 Tomás Ruiz-Lara , Tadafumi Matsuno , S. Sofie Lövdal , Amina Helmi , Emma Dodd , Helmer H. Koppelman

In this paper we present a new chemical evolution model for the Galaxy which assumes two main infall episodes for the formation of halo-thick disk and thin disk, respectively. We do not try to take into account explicitly the evolution of…

Astrophysics · Physics 2009-10-28 C. Chiappini , F. Matteucci , R. Gratton

We study the behaviour of multiple radiative cooling algorithms implemented in seven Semi-Analytic Models (SAMs) of galaxy formation, including a new model we propose in this paper. We use versions of the models without feedback and apply…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-29 Yu Lu , Dušan Kereš , Neal Katz , H. J. Mo , Mark Fardal , Martin D. Weinberg

The metallicity structure of stellar halos encodes the fossil record of galaxy assembly, tracing the chemical evolution and dynamical imprint of past mergers. Using five Milky Way-mass halos from the Aquarius simulations, we introduce an…

Astrophysics of Galaxies · Physics 2025-12-01 Amit Mondal , Biswajit Pandey

Based on a model of globular cluster self-enrichment published in a previous paper, we present an explanation for the metallicity gradient observed throughout the galactic Old Halo. Our self-enrichment model is based on the ability of…

Astrophysics · Physics 2007-05-23 G. Parmentier , E. Jehin , P. Magain , A. Noels , A. Thoul