Related papers: Wolf-Rayet Stars as IMF Probes
Using the latest stellar evolution models, theoretical stellar spectra, and a compilation of observed emission line strengths from Wolf-Rayet (WR) stars, we construct evolutionary synthesis models for young starbursts. We explicitly…
Using a code that employs a self-consistent method for computing the effects of photoionization on circumstellar gas dynamics, we model the formation of wind-driven nebulae around massive Wolf-Rayet (W-R) stars. Our algorithm incorporates a…
I review efforts to determine the form and any lower limit to the initial mass function in the Galactic disk, using observations of low-mass stars and brown dwarfs in the field, young clusters and star forming regions. I focus on the…
Aims: We investigate the massive stellar content of the nearby dwarf irregular Wolf-Rayet galaxy IC 4662, and consider its global star forming properties in the context of other metal-poor galaxies, the SMC, IC 10 and NGC 1569. Methods:…
The birth of stars and the formation of galaxies are cornerstones of modern astrophysics. While much is known about how galaxies globally and their stars individually form and evolve, one fundamental property that affects both remains…
The history of the IMF in starburst regions is reviewed. The IMFs are no longer believed to be top-heavy, although some superstar clusters, whether in starburst regions or not, could be. General observations of the IMF are discussed to put…
In the star formation process, the vital impact of environmental factors such as feedback from massive stars and stellar density on the form of the initial mass function (IMF) at low-mass end is yet to be understood. Hence a systematic,…
(abridged) The {stellar IMF} has been found to be essentially invariant. While some apparent differences are seen, the uncertainties inherent to this game do not allow a firm conclusion to be made that the IMF varies systematically with…
Initial results, techniques, and rationale for a near-infrared survey of evolved emission-line stars toward the Galactic Center are presented. We use images taken through narrow-band emission-line and continuum filters to select candidates…
Extremely metal-poor, high-ionizing starbursts in the local Universe provide unique laboratories for exploring in detail the physics of high-redshift systems. Also, their ongoing star-formation and haphazard morphology make them outstanding…
We present refined color-color selection criteria for identifying Wolf-Rayet (WR) stars using available mid infrared (MIR) photometry from WISE in combination with near infrared (NIR) photometry from 2MASS. Using a sample of spectrally…
We summarize past and current surveys for Wolf-Rayet stars among the Local Group galaxies, emphasizing both the how and the why. Such studies are invaluable for helping us learn about massive star evolution, and for providing sensitive…
Massive relic galaxies formed the bulk of their stellar component before z~2 and have remained unaltered since then. Therefore, they represent a unique opportunity to study in great detail the frozen stellar population properties of those…
The dependence of the stellar initial mass function (IMF) on star-formation environment, particularly at low metallicities and high redshifts, remains poorly constrained. Ultra-faint dwarf galaxies (UFDs) are local fossils of high-redshift…
The stellar initial mass function (IMF) is a fundamental astrophysical quantity that impacts a wide range of astrophysical problems from heavy element distribution to galactic evolution to planetary system formation. However, the origin and…
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)…
The optical/near-IR stellar continuum carries unique information about the stellar population in a galaxy, its mass function and star-formation history. Star-forming regions display rich emission-line spectra from which we can derive the…
It has been shown recently that the dynamical V-band mass-to-light ratios of compact stellar systems with masses from 10^6 to 10^8 Solar masses are not consistent with the predictions from simple stellar population (SSP) models. Top-heavy…
Aims. We have gathered optical spectra of 8 long-duration GRB host galaxies selected from the archival data of VLT/FORS2. We investigated whether or not Wolf-Rayet (WR) stars can be detected in these GRB host galaxies. We also tried to…
A number of recent studies have proposed that the stellar initial mass function (IMF) of early type galaxies varies systematically as a function of galaxy mass, with higher mass galaxies having bottom heavy IMFs. These bottom heavy IMFs…