Related papers: Massive and Evolved Stars with the ngVLA
Massive stars have strong stellar winds that direct their evolution through the upper Hertzsprung-Russell diagram and determine the black hole mass function. Secondly, wind strength dictates the atmospheric structure that sets the ionising…
When planet-hosting stars evolve off the main sequence and go through the red-giant branch, the stars become orders of magnitudes more luminous and, at the same time, lose mass at much higher rates than their main-sequence counterparts.…
The current state-of-the-art of multi-wavelength diagnostic tools (evolutionary synthesis, photoionisation models) for massive star forming regions (HII regions, starbursts, etc.) and some of their input physics (especially model…
We show that, if many GRBs are indeed produced by the collapse of massive stars, GRBs and their afterglows provide a powerful probe of the very high redshift (z > 5) universe.
We discuss the role of mass loss for the evolution of the most massive stars, highlighting the role of the predicted bi-stability jump that might be relevant for the evolution of rotational velocities during or just after the main sequence.…
The combination of deep exposures and high resolution offered by telescopes in space allows the detection of lensing over a wide range of source redshifts and lens masses. As an example, we model a lens candidate found in the southern…
Gamma-Ray Bursts (GRBs) are extra-galactic and extremely energetic transient emissions of gamma rays, which are thought to be associated with the death of massive stars or the merger of compact objects in binary systems. Their huge…
In a high-mass X-ray binary (HMXB) a massive star interacts with a neutron-star or black-hole companion in various ways. The gravitational interaction enables the measurement of fundamental parameters such as the mass of both binary…
Multi-wavelength centimeter continuum observations of non-dusty, non-pulsating K spectral-type red giants directly sample their chromospheres and wind acceleration zones. Such stars are feeble emitters at these wavelengths however, and…
Despite their paucity, massive hot stars are real cosmic engines of fundamental importance in shaping our Universe, from its very early stages up to its current appearance. Understanding the physics of massive stars is then a key issue for…
Most massive galaxies are now thought to go through an Active Galactic Nucleus (AGN) phase one or more times. Yet, the cause of triggering and the variations in the intrinsic and observed properties of AGN population are still poorly…
Although rare, massive stars, being the main sources of ionizing radiation, chemical enrichment and mechanical energy in the Galaxy, are the most important objects of the stellar population. This review presents the many different aspects…
Radio observations were used to detect the `active' galaxy population within rich clusters of galaxies in a non-biased manner that is not plagued by dust extinction or the K-correction. We present wide-field radio, optical (imaging and…
[Abridged] Context: Radiation-driven mass loss plays a key role in the life-cycles of massive stars. However, basic predictions of such mass loss still suffer from significant quantitative uncertainties. Aims: We develop new…
Massive stars lose a large fraction of their mass to radiation-driven winds throughout their entire life. These outflows impact both the life and death of these stars and their surroundings. Theoretical mass-loss rates of hot, massive stars…
As a byproduct of its search for the first star forming galaxies, NGST will obtain high-quality spectra for thousands of galaxies in the redshift range z = 0 - 6 and beyond. Most of the galaxies will possess strong emission-line spectra,…
Most stars will experience episodes of substantial mass loss at some point in their lives. For very massive stars, mass loss dominates their evolution, although the mass loss rates are not known exactly, particularly once the star has left…
The most massive stars dominate the chemical enrichment, mechanical and radiative feedback, and energy budget of their host environments. Yet how massive stars initially form and how they evolve throughout their lives is ambiguous. The mass…
We present selected results from our ongoing investigation of high-mass star-forming regions which are based on infrared observations with ESO's ISAAC camera at the 8.2-m ANTU VLT telescope. Although these young stellar objects comprise a…
The study of massive X-ray binaries provides important observational diagnostics for a number of fundamental astrophysical issues, such as the evolution of massive stars, the stellar winds of massive stars, the formation of compact objects…