Related papers: Why Do Stars Turn Red? II. Steady-State Envelope S…

Red supergiant stars (RSGs) are massive stars in a late stage of evolution, crucial for understanding stellar life cycles and Galactic structure. However, RSGs on the far side of our Galaxy have been underexplored due to observational…

(Abridged). We introduce the Aarhus Red Giants Challenge, a series of detailed comparisons between widely used stellar evolution and oscillation codes aiming at establishing the minimum level of uncertainties in properties of red giants…

The empirical evidence for an upper mass limit for the red supergiant (RSG) progenitors of the Type II-P SNe at about 18 Msun, raises questions about the fate of the most luminous, most massive RSGs. These stars may evolve back to warmer…

Current observations of the Galactic Center (GC) seem to display a core-like distribution of bright stars from $\sim 5"$ inwards. On the other hand, we observe young, massive stars at the GC, with roughly 20-50\% of them in a disc, mostly…

The mass loss rates of red supergiants (RSGs) govern their evolution towards supernova and dictate the appearance of the resulting explosion. To study how mass-loss rates change with evolution we measure the mass-loss rates (\mdot) and…

The JWST discovery of "Little Red Dots" (LRDs) has revealed a population of compact, red sources at $z \sim 5-10$ that likely host supermassive black holes (SMBHs). Recent observations of the gravitationally lensed LRD R2211-RX1 reveal…

Identifications of red supergiants (RSGs) in the Milky Way and nearby galaxies have experienced an exponential increase in recent years, driven by advancements in selection techniques, the continued expansion of archival datasets, and a…

Massive stars with a core-halo structure are interesting objects for stellar physics and hydrodynamics. Using simulations for stellar evolution, radiation hydrodynamics, and radiative transfer, we study the explosion of stars with an…

We investigate the red supergiant (RSG) population of M31, obtaining radial velocities of 255 stars. These data substantiate membership of our photometrically-selected sample, demonstrating that Galactic foreground stars and extragalactic…

We provide a status report on the determination of stellar ages from asteroseismology for stars of various masses and evolutionary stages. The ability to deduce the ages of stars with a relative precision of typically 10 to 20% is a unique…

We present evolutionary synthesis models applied to near--infrared spectral features observed in the spectra of young Magellanic Cloud clusters and starburst galaxies. The temporal evolution of the first and second overtones of CO at 2.29…

We present a new sample of strong gravitational lens systems where both the foreground lenses and background sources are early-type galaxies. Using imaging from HST/ACS and Keck/NIRC2, we model the surface brightness distributions and show…

We identify red supergiants (RSGs) in our spiral neighbors M31 and M33 using near-IR (NIR) photometry complete to a luminosity limit of log L/Lo=4.0. Our archival survey data cover 5 deg^2 of M31, and 3 deg^2 for M33, and are likely…

Star formation in galaxies is triggered by a combination of processes, including gravitational instabilities, spiral wave shocks, stellar compression, and turbulence compression. Some of these persist in the far outer regions where the…

According to the standard inside-out galaxy formation scenario, galaxies first form a dense core and then gradually assemble their outskirts. This implies that galaxies with similar central stellar mass densities might have evolutionary…

We discuss the properties of the host galaxy and ring light distributions in the optical and near infrared bands for a sample of Polar Ring Galaxies (PRGs), presented in Paper I (Iodice et al. 2002, Paper I). The goal of this work is to…

In the context of the determination of stellar properties using asteroseismology, we study the influence of rotation and convective-core overshooting on the properties of red-giant stars. We used models in order to investigate the effects…

Instability of population I (X=0.7, Y=0.02) massive stars against radial oscillations during the post-main sequence gravitational contraction of the helium core is investigated. Initial stellar masses are in the range from 65M_\odot to…

Using cosmological simulations, we address the properties of high-redshift star-forming galaxies (SFGs) across their main sequence (MS) in the plane of star-formation rate (SFR) versus stellar mass. We relate them to the evolution of…

We present modeling research work of the winds and circumstellar environments of prototypical hot and cool massive stars using advanced radiative transfer (RT) calculations. This research aims at unraveling the detailed physics of various…