相关论文: Outskirts of spiral galaxies: result of a secular …
We present our recent results on the cosmic evolution of the outskirst of disk galaxies. In particular we focus on disk-like galaxies with stellar disk truncations. Using UDF, GOODS and SDSS data we show how the position of the break (i.e.…
We have conducted the largest systematic search so far for stellar disk truncations in disk-like galaxies at intermediate redshift (z<1.1), using the Great Observatories Origins Deep Survey South (GOODS-S) data from the Hubble Space…
The mechanism causing breaks in the radial surface brightness distribution of spiral galaxies is not yet well known. Despite theoretical efforts, there is not a unique explanation for these features and the observational results are not…
We have conducted a systematic search for stellar disk truncations in disk-like galaxies at intermediate redshift (z<1.1) using the Hubble Ultra Deep Field (UDF) data. We use the position of the truncation as a direct estimator of the size…
In the light of several recent developments we revisit the phenomenon of galactic stellar disk truncations. Even 25 years since the first paper on outer breaks in the radial light profiles of spiral galaxies, their origin is still unclear.…
We investigate the evolution of galactic disks in N-body Tree-SPH simulations. We find that disks, initially truncated at three scale-lengths, can triple their radial extent, solely driven by secular evolution. Both Type I (single…
The outer disks of galaxies present a unique laboratory for studying the process of disk formation. A considerable fraction of observed disks exhibit a break in their surface brightness profiles. The ubiquity of these features points to a…
The properties and star formation processes in the far-outer disks of nearby spiral and dwarf irregular galaxies are reviewed. The origin and structure of the generally exponential profiles in stellar disks is considered to result from…
We present deep optical imaging of three face-on disk galaxies together with a detailed description of the reduction and calibration methods used, in order to measure the intrinsic shape of their outer stellar edges. Whereas it is now well…
We have in recent years come to view the outer parts of galaxies as having vital clues about their formation and evolution. Here, we would like to briefly present our results from a complete sample of nearby, late-type, spiral galaxies,…
The extreme outer regions of disk galaxies, lying at or beyond the classical optical radius defined by R25, present an opportunity to study star formation and chemical evolution under unique physical conditions, possibly reminscent of those…
We have performed a high mass and force resolution simulation of an idealized galaxy forming from dissipational collapse of gas embedded in a spherical dark matter halo. The simulation includes star formation and effects of stellar…
We present deep color profiles for a sample of 415 disk galaxies within the redshift range 0.1<z<=1.1, and contained in HST-ACS imaging of the GOODS-South field (Giavalisco et al. 2004). For each galaxy, passband combinations are chosen to…
We have performed a large observing campaign of intermediate-redshift disk galaxies including spectroscopy with the FORS instruments of the VLT and imaging with the Advanced Camera for Surveys onboard the HST. Our data set comprises 113…
We summarize the results obtained from our suite of chemical evolution models for spiral disks, computed for different total masses and star formation efficiencies. Once the gas, stars and star formation radial distributions are reproduced,…
We present SPH cosmological simulations of the formation of three disk galaxies with a detailed treatment of chemical evolution and cooling. The resulting galaxies have properties compatible with observations: relatively high disk-to-total…
We analyse a high-resolution, fully cosmological, hydrodynamical disc galaxy simulation, to study the source of the double-exponential light profiles seen in many stellar discs, and the effects of stellar radial migration upon the…
Our understanding of how the size of galaxies has evolved over cosmic time is based on the use of the half-light (effective) radius as a size indicator. Although the half-light radius has many advantages for structurally parameterising…
Radial and vertical profiles are determined for a sample of 34 edge-on disk galaxies in the HDFs, selected for their apparent diameter larger than 1.3 arcsec and their unperturbed morphology. The thickness and flatness of their galactic…
Based on VLT/FORS spectroscopy and HST/ACS imaging, we have constructed a sample of ~200 field spiral galaxies that cover redshifts up to z~1. Such a large data set allows to study the evolution of fundamental galaxy parameters like…