相关论文: The Initial Mass Function of the Inner Galaxy Meas…

Aims. We seek to probe the Galactic bulge IMF starting from microlensing observations. Methods. We analyse the recent results of the microlensing campaigns carried out towards the Galactic bulge presented by the EROS, MACHO and OGLE…

We developed a parametric Galactic model toward the Galactic bulge by fitting to spatial distributions of the Gaia DR2 disk velocity, VVV proper motion, BRAVA radial velocity, OGLE-III red clump star count, and OGLE-IV star count and…

We use recent microlensing observations toward the central bulge of the Galaxy to probe the overall stellar plus brown dwarf initial mass function (IMF) in these regions well within the brown dwarf domain. We find that the IMF is consistent…

Gravitational microlensing depends primarily on the lens mass and presents a larger occurrence rate in crowded regions, which makes it the best tool to uncover the initial mass function (IMF) of low-mass stars in the Galactic bulge. The…

We present a new approach in the study of the Initial Mass function (IMF) in external galaxies based on quasar microlensing observations. We use measurements of quasar microlensing magnifications in 24 lensed quasars to estimate the average…

We present a luminosity function (LF) for lower main sequence stars in the Galactic bulge near (l,b)=(0,-6) to J=24, corresponding to M_J~9.3. This LF is derived from HST + NICMOS observations with the F110W and F160W filters. The main…

Recent work has suggested that the stellar initial mass function (IMF) is not universal, but rather is correlated with galaxy stellar mass, stellar velocity dispersion, or morphological type. In this paper, we investigate variations of the…

The number and properties of observed gravitational microlensing events depend on the distribution and kinematics of stars and other compact objects along the line of sight. In particular, precise measurements of the microlensing optical…

The stellar initial mass function (IMF) is a fundamental property in the measurement of stellar masses and galaxy star formation histories. In this work we focus on the most massive galaxies in the nearby universe…

Mass measurements and absorption line studies indicate that the stellar initial mass function (IMF) is bottom-heavy in the central regions of many early-type galaxies, with an excess of low mass stars compared to the IMF of the Milky Way.…

Systematic variations of the IMF in early-type galaxies, and their connection with possible drivers such as velocity dispersion or metallicity, have been much debated in recent years. Strong lensing over galaxy scales combined with…

Searches for gravitational microlensing events are traditionally concentrated on the central regions of the Galactic bulge but many microlensing events are expected to occur in the Galactic plane, far from the Galactic Center. Owing to the…

We present and study the largest and the most comprehensive catalog of microlensing events ever constructed. The sample of standard microlensing events comprises 3718 unique events from years 2001--2009, with 1409 not detected before in…

We derive a semi-empirical galactic initial mass function (IMF) from observational constraints. We assume that the star formation rate in a galaxy can be expressed as the product of the IMF, $\psi (m)$, which is a smooth function of mass…

I show that by observing microlensing events both astrometrically and photometrically, the Space Interferometry Mission (SIM) can measure the mass function of stellar remnants in the Galactic bulge including white dwarfs, neutron stars, and…

We present constraints on the stellar initial mass function (IMF) in two ultra-faint dwarf (UFD) galaxies, Hercules and Leo IV, based on deep HST/ACS imaging. The Hercules and Leo IV galaxies are extremely low luminosity (M_V = -6.2, -5.5),…

Because direct measurements require resolved stellar populations including low-mass stars, determining the stellar initial mass function (IMF) has been a historically difficult problem even within our own Galaxy and impossible everywhere…

We determine an absolute calibration of the initial mass function (IMF) of early-type galaxies, by studying a sample of 56 gravitational lenses identified by the SLACS Survey. Under the assumption of standard Navarro, Frenk & White dark…

The stellar initial mass function (IMF) is a fundamental property of star formation, offering key insight into the physics driving the process as well as informing our understanding of stellar populations, their by-products, and their…

It is now well-established that the stellar initial mass function (IMF) can be determined from the absorption line spectra of old stellar systems, and this has been used to measure the IMF and its variation across the early-type galaxy…