相关论文: Galaxy Number Counts
Low Surface-Brightness (LSB) galaxies are severely underrepresented in surveys used to define the local luminosity function (LF), but could it in principle be detected in deep surveys. To explore the possible contribution of such objects to…
We set out to quantify the number density of quiescent massive compact galaxies at intermediate redshifts. We determine structural parameters based on i-band imaging using the CFHT equatorial SDSS Stripe 82 (CS82) survey (~170 sq. degrees)…
The evolution of masses and sizes of passive (early-type) galaxies with redshift provides ideal constraints to galaxy formation models. These parameters can in principle be obtained for large galaxy samples from multi-band photometry alone.…
The excess numbers of blue galaxies at faint magnitudes are a long-standing cosmological puzzle. We present new number-magnitude counts as a function of galactic morphology from the first deep fields of the Cycle 4 Hubble Space Telescope…
Cluster number counts offer sensitive probes of the dark energy if and only if the_evolution_ of the cluster mass versus observable relation(s) is well calibrated. We investigate the potential for internal calibration by demanding…
Strong gravitational lensing along with the distance sum rule method can constrain both cosmological parameters as well as density profiles of galaxies without assuming any fiducial cosmological model. To constrain galaxy parameters and…
We compare observations of the high redshift galaxy population to the predictions of the galaxy formation model of Croton et al. (2006) and De Lucia & Blaizot (2006). This model, implemented on the Millennium Simulation of the concordance…
The XMM--LSS project is detecting distant clusters of low mass, quite comparable in mass to the ones in the local universe. This allows a direct comparison of galaxy properties at different redshifts in ``similar'' clusters. We present here…
The redshift dependence of the luminosity density in certain wavebands (e.g. UV and H-alpha) can be used to infer the history of star formation in the populations of galaxies producing this luminosity. This history is a useful datum in…
We present a combined study of the colour-magnitude relation, colour distribution and luminosity function of a sample of 24 clusters at redshifts 0.3<z<1. The sample is largely composed of X-ray selected/detected clusters. Most of the…
We study up to second order the galaxy number over-density that depends on magnification in redshift space on cosmological scales for a concordance model. The result contains all general relativistic effects up to second order which arise…
Recent JWST observations have revealed a large population of quiescent galaxies (QGs) at high redshift ($z \sim 4-8$), challenging current models of early galaxy formation and quenching. Accurate number density estimates are crucial but…
Clusters of galaxies are important laboratories for understanding both galaxy evolution and constraining cosmological quantities. Any analysis of clusters, however, is best done when one can reliably determine which galaxies are members of…
We study the evolution of galaxy clustering in various cosmological models with quintessence. We investigate how the analytical predictions vary with change of dark energy equation of state $w_X$. Comparing these predictions against…
Interpretation of data from faint dwarf galaxies is made challenging by observations limited to only the brightest stars. We present a major improvement to tackle this challenge by undertaking zoomed cosmological simulations that resolve…
We constrain the evolution of the galaxy mass and luminosity functions from the analysis of (public) multi-wavelength data in the Chandra Deep Field South (CDFS) area, obtained from the GOODS and other projects, and including very deep…
Connecting galaxies with their descendants (or progenitors) at different redshifts can yield strong constraints on galaxy evolution. Observational studies have historically selected samples of galaxies using a physical quantity, such as…
Dwarf galaxies represent a powerful probe of annihilating dark matter particle models, with gamma-ray data setting some of the best bounds available. A major issue in improving over existing constraints consists in the limited knowledge of…
Deep mid-infrared (MIR) observations could reveal a population of faint, high-redshift (z>3) dusty starburst galaxies that are the progenitors of present-day spheroids or bulges, and are beyond the reach of current instruments. We utilize a…
We are carrying out a comprehensive multi-wavelength study of dwarf galaxies in the Local Volume (< 5 Mpc). After our all-sky survey more than doubled the dwarf census we are now measuring structural parameters, integrated properties, and…