相关论文: Mapping Accreted Stars in Early-Type Galaxies Acro…
The hierarchical model of galaxy evolution suggests that the impact of mergers is substantial on the intricate processes that drive stellar assembly within a galaxy. However, accurately measuring the contribution of accretion to a galaxy's…
We examine galaxy formation in a cosmological AMR simulation, which includes two high resolution boxes, one centered on a 3 \times 10^14 M\odot cluster, and one centered on a void. We examine the evolution of 611 massive (M\ast >…
Modern observational and analytic techniques now enable the direct measurement of star formation histories and the inference of galaxy assembly histories. However, current theoretical predictions of assembly are not ideally suited for…
In the two-phase scenario of galaxy formation, a galaxy's stellar mass growth is first dominated by in-situ star formation, and subsequently by accretion. We analyse the radial distribution of the accreted stellar mass in ~500 galaxies from…
We use the Illustris simulation to study the relative contributions of in situ star formation and stellar accretion to the build-up of galaxies over an unprecedentedly wide range of masses ($M_{\ast} = 10^9-10^{12} \, {\rm M_{\odot}}$),…
In this paper we measure the merger fraction and rate, both minor and major, of massive early-type galaxies (M_star >= 10^11 M_Sun) in the COSMOS field, and study their role in mass and size evolution. We use the 30-band photometric…
We analyse the mass assembly of central galaxies in the EAGLE hydrodynamical simulations. We build merger trees to connect galaxies to their progenitors at different redshifts and characterize their assembly histories by focusing on the…
We present the results of a series of empirical computations regarding the role of major mergers in forming the stellar masses of modern galaxies based on measurements of galaxy merger and star formation histories from z~0.5-3. We…
We use the GALFORM semi-analytical model of galaxy formation and the Planck-Millennium simulation to investigate the origins of stellar mass in galaxies and their spheroids. We compare the importance of mergers and disc instabilities, as…
Understanding the origin of stars within a galaxy - whether formed in-situ or accreted from other galaxies (ex-situ) - is key to constraining its evolution. Spatially resolving these components provides crucial insights into a galaxy's mass…
Recent work has suggested that the amplitude of the size mass relation of massive early type galaxies evolves with redshift. Here we use a semi-analytical galaxy formation model to study the size evolution of massive early type galaxies. We…
Quantifying the contribution of mergers to the stellar mass of galaxies is key for constraining the mechanisms of galaxy assembly across cosmic time. However, the mapping between observable galaxy properties and merger histories is not…
Cosmological simulations of galaxy formation appear to show a two-phase character with a rapid early phase at z>2 during which in-situ stars are formed within the galaxy from infalling cold gas followed by an extended phase since z<3 during…
We determine the evolution of the co-moving density of the most massive ($M_* \geq 10^{12} M_\odot$) early-type galaxy population in the redshift range of $z = 0.15$ - 0.45 in different stellar mass ranges using data from the Sloan Digital…
We present constraints on the formation and evolution of early-type galaxies (ETGs) with the empirical model EMERGE. The parameters of this model are adjusted so that it reproduces the evolution of stellar mass functions, specific star…
Galaxy mergers are known to trigger bursts of central star formation, which should therefore lead to stellar mass growth in their inner regions. However, observational measurements of this `burst mass fraction' are scant. Here, we assemble…
Massive galaxies, such as nearby ellipticals, have relatively low number densities, yet they host the majority of the stellar mass in the universe. Understanding their origin is a central problem of galaxy formation. Age dating of stellar…
Early-type galaxies are considered to be the end-products of massive galaxy formation. Optical spectroscopic studies reveal that massive early-type galaxies formed the bulk of their stars over short timescales (1<Gyr) and at high redshift…
We present a comprehensive analysis of galaxy close-pair fractions and major merger rates to evaluate the importance of mergers in the hierarchical growth of galaxies over cosmic time. This study focuses on the previously poorly understood…
The growth of galaxies is a key problem in understanding the structure and evolution of the universe. Galaxies grow their stellar mass by a combination of star formation and mergers, with a relative importance that is redshift dependent.…