Related papers: The distinguishing factor for gravity models: stel…
One of the most important properties of a galaxy is the total stellar mass, or equivalently the stellar mass-to-light ratio (M/L). It is not directly observable, but can be estimated from stellar population synthesis. Currently, a galaxy's…
(abridged) We found in previous studies that standard Simple Stellar Population (SSP) models are unable to describe or explain the colours of Galactic open clusters both in the visible and in the NIR spectral range. (...) We construct a…
Although the modified dynamics (MOND) proposed by Milgrom successfully accounts for the systematics of galaxy rotation curves and cluster dynamics without invoking dark matter, the idea remains a largely ad hoc modification of Newtonian…
(Abridged) By means of high-resolution cosmological simulations in the context of the LCDM scenario, the specific star formation rate (SSFR=SFR/Ms, Ms is the stellar mass)--Ms and stellar mass fraction (Fs=Ms/Mh, Mh is the halo mass)--Ms…
Low-acceleration space-time scale invariant dynamics (SID, Milgrom 2009a) predicts two fundamental correlations known from observational galactic dynamics: the baryonic Tully-Fisher relation (BTFR) and a correlation between the observed…
Within a galaxy the stellar mass-to-light ratio $\Upsilon_*$ is not constant. Spatially resolved kinematics of nearby early-type galaxies suggest that allowing for a variable initial mass function (IMF) returns significantly larger…
We here present the first spatially-resolved study of the IMF in external galaxies derived using a dynamical tracer of the mass-to-light ratio. We use the kinematics of relaxed molecular gas discs in seven early-type galaxies (ETGs)…
Most structural and evolutionary properties of galaxies strongly rely on the stellar initial mass function (IMF), namely the distribution of the stellar mass formed in each episode of star formation. As the IMF shapes the stellar population…
The modified newtonian dynamics (MOND) paradigm of Milgrom can boast of a number of successful predictions regarding galactic dynamics; these are made without the assumption that dark matter plays a significant role. MOND requires…
The remarkably tight relationship between galaxy optical color and stellar mass-to-light ratio ($M_*/L$) is widely used for efficient stellar mass estimates. However, it remains unclear whether this low scatter comes from a natural order in…
Aims. We present here a new theoretical approach to population synthesis. The aim is to predict colour magnitude diagrams (CMDs) for huge numbers of stars. With this method we generate synthetic CMDs for N-body simulations of galaxies.…
We investigate with unprecedented accuracy the correlations between the dynamical mass-to-light ratio M/L and other global observables of E and S0 galaxies. We construct two-integral Jeans and three-integral Schwarzschild dynamical models…
We review galaxy formation and dynamics under the MOND hypothesis of modified gravity, and compare to similar galaxies in Newtonian dynamics with dark matter. The aim is to find peculiar predictions both to discriminate between various…
The colour and metallicity gradients observed in spiral galaxies suggest that the mass-to-light ratio (M*/L) of the stellar disc is a function of radius. This is indeed predicted by chemo-photometric models of galactic discs. We investigate…
We use a sample of ~16,000 non-emission line galaxies from the SDSS to investigate the physical parameters underlying the well-known color-magnitude and color-sigma relations. Galaxies are sorted in terms of velocity dispersions (sigma),…
This work aims to study the distribution of luminous and dark matter in Coma early-type galaxies. Dynamical masses obtained under the assumption that mass follows light do not match with the masses of strong gravitational lens systems of…
Three component models of the IMF are made to consider possible origins for the observed relative variations in the numbers of brown dwarfs, solar-to-intermediate mass stars, and high mass stars. Three distinct physical processes are noted.…
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…
I estimate MOND M/L values for nine galaxy groups that were recently studied by Tully et al.. Instead of the large M/L values that they find with Newtonian dynamics (up to 1200 solar units) the MOND estimates cluster around 1 solar unit.…
We estimate ages, metallicities, $\alpha$-element abundance ratios and stellar initial mass functions of elliptical (E) and S0 galaxies from the MaNGA-DR15 survey. We stack spectra and use a variety of single stellar population synthesis…