相关论文: Are Local Group Dwarf Spheroidal Galaxies the Firs…
Using a currently most representative sample of 477 late-type galaxies within 11 Mpc of the Milky Way with measured star-formation rates ($SFR$s) from the far ultraviolet ($FUV$) and H$\alpha$ emission line fluxes, we select galaxies with…
Low-mass dwarf galaxies are very sensitive test-beds for theories of cosmic structure formation since their weak gravitational fields allow the effects of the relevant physical processes to clearly stand out. Up to now, no unified account…
The demographics of dwarf galaxy populations have long been in tension with predictions from the Cold Dark Matter (CDM) paradigm. If primordial density fluctuations were scale-free as predicted, dwarf galaxies should themselves host dark…
We present results from a fully cosmological, very high-resolution, LCDM "zoom-in" simulation of a group of seven field dwarf galaxies with present-day virial masses in the range M_vir=4.4e8-3.6e10 Msun. The simulation includes a blastwave…
We analyse the environment of low redshift, z < 0.2, SDSS quasars using the spectral and photometric information of galaxies from the Sloan Digital Sky Survey Third Data Release (SDSS-DR3). We compare quasar neighbourhoods with field and…
We derive and analyse the star formation histories of 393 intermediate-redshift (0.1 $\leq$ z $\leq$ 0.9) galaxies with stellar masses between $\sim$10$^{8}$ - 10$^{12}$ M$_{\odot}$. We probe a cosmic time of approximately 6 Gyr and a range…
Dwarf spheroidal galaxies are regarded as the basic building blocks in the formation of larger galaxies and are believed to be the most dark matter dominated systems known in the Universe. There are several models that attempt to explain…
We present observational evidence of environmental effects on the formation and evolution of planetary systems. We combine catalogues of resolved protoplanetary discs (PPDs) and young stellar objects in the solar neighbourhood to analyse…
Our knowledge about the dynamics, the chemical abundances and the evolutionary histories of the more luminous dwarf spheroidal (dSph) galaxies is constantly growing. However, very little is known about the enrichment of the ultra-faint…
We explore some of the ramifications arising from superflares on the evolutionary history of Earth, other planets in the Solar system, and exoplanets. We propose that the most powerful superflares can serve as plausible drivers of…
The prospects for the habitability of M-dwarf planets have long been debated, due to key differences between the unique stellar and planetary environments around these low-mass stars, as compared to hotter, more luminous Sun-like stars.…
We use recent HST colour-magnitude diagrams of the resolved stellar populations of a sample of local dSph galaxies (Carina, LeoI, LeoII, Ursa Minor and Draco) to infer the star formation histories of these systems, $SFR(t)$. Applying a new…
The Galactic dwarf spheroidal galaxies (dSphs) provide valuable insight into dark matter (DM) properties and its role in galaxy formation. Their close proximity enables the measurement of line-of-sight velocities for resolved stars, which…
The paucity of observed dwarf galaxies in the Local Group relative to the abundance of predicted dark matter halos remains one of the greatest puzzles of the LCDM paradigm. Solving this puzzle now requires not only matching the numbers of…
We infer the UV luminosities of Local Group galaxies at early cosmic times ($z \sim 2$ and $z \sim 7$) by combining stellar population synthesis modeling with star formation histories derived from deep color-magnitude diagrams constructed…
Earth-scale planets in the classical habitable zone (HZ) are more likely to be habitable if they possess active geophysics. Without a constant internal energy source, planets cool as they age, eventually terminating tectonic activity and…
The closest potentially habitable worlds outside our Solar system orbit a different kind of star than our Sun: smaller red dwarf stars. Such stars can flare frequently, bombarding their planets with biologically damaging high-energy UV…
The analysis of the early star formation history (SFH) of nearby galaxies, obtained from their resolved stellar populations is relevant as a test for cosmological models. However, the early time resolution of observationally derived SFHs is…
Dwarf galaxies with stellar masses around 10^9 Msun can be explored at high and low redshifts and they give a glimpse of the different conditions of galaxy formation at different epochs. Using a large sample of about 300 zoom-in…
In our search for life beyond the Solar System, certain planetary bodies may be more conducive to life than Earth. However, the observability of these `superhabitable' planets in the habitable zones around K dwarf stars has not been fully…