Related papers: Enhanced mass-loss rate evolution of stars with $\…
Recent asteroseismic determinations of {\Delta}M, the integrated mass loss on the red giant branch (RGB), for fields stars show a trend of {\Delta}M decreasing as metallicity increases. This trend among field stars is inconsistent with many…
Extreme helium stars are very rare low-mass supergiants in a late stage of evolution. They are probably contracting to become white dwarfs following a violent phase of evolution which caused them to become hydrogen-deficient giants,…
We present new two-dimensional radiation hydrodynamic simulations of supernova shock breakout from red supergiants using the $\texttt{CASTRO}$ code. Our progenitors are 20 and 25 M$_{\odot}$ solar-metallicity stars evolved from the zero-age…
There is evidence that some red supergiants (RSGs) experience short lived phases of extreme mass loss, producing copious amounts of dust. These episodic outburst phases help to strip the hydrogen envelope of evolved massive stars,…
I propose a scenario according to which the dense compact circumstellar matter (CSM) that the ejecta of many core collapse supernovae (CCSNe) collide with within several days after explosion results from a dense zone where in addition to…
A model for the chemical evolution of the intergalactic medium (IGM) is presented using theoretical yields of very massive stars (VMSs) and Type II supernovae (SNe II). It is shown that if [Si/C] is indeed as high as ~0.7 in the IGM, then…
We present a new grid of presupernova models of massive stars extending in mass between 13 and 120 Msun, covering four metallicities (i.e. [Fe/H]=0, -1, -2 and -3) and three initial rotation velocities (i.e. 0, 150 and 300 km/s). The…
We investigate the formation of red misfits (RM) using a cosmological, hydrodynamical simulation from the $\rm \small EAGLE$ project. Similar to observations, the RM possess less dust, higher stellar metallicities, and older stellar…
Context. Red supergiants are observed to undergo vigorous mass-loss. However, to date, no theoretical model has succeeded in explaining the origins of these objects' winds. This strongly limits our understanding of red supergiant evolution…
The observations of high redshifts quasars at $z\gtrsim 6$ have revealed that supermassive black holes (SMBHs) of mass $\sim 10^9\,\mathrm{M_{\odot}}$ were already in place within the first $\sim$ Gyr after the Big Bang. Supermassive stars…
We present a comprehensive study of the star-forming main sequence (SFMS) and its scatter at redshifts $3 \leq z \leq 9$, using NIRCam photometry from the JADES survey in the GOODS-S and GOODS-N fields. Our analysis is based on a sample of…
Massive stars undergoing iron core-collapse at the end of their evolution terminate their lives either in successful or failed supernovae (SNe). The physics of core-collapse supernovae (CCSNe) is complex, and their understanding requires…
We investigate the resolved star formation properties of a sample of 45 massive galaxies (M_*>10^11M_solar) within a redshift range of 1.5 < z < 3 detected in the GOODS NICMOS Survey (Conselice et al. 2011), a HST H-band imaging program. We…
Red Midcourse Space Experiment (MSX) Sources (RMSs) are regarded as excellent candidates of massive starforming regions. In order to characterize the chemical properties of massive star formation, we made a systematic study of 87 RMSs in…
Massive stars are the main objects that illuminate H II regions and they evolve quickly to end their lives in core-collapse supernovae (CCSNe). Thus it is important to investigate the association between CCSNe and H II regions. In this…
The relationship between the mass-loss history and final evolutionary stage of massive stars and the properties of the observable supernova (SN) is still under debate. This is especially true for stripped-envelope (Type Ib/c) SNe, where the…
We study how runaway stellar collisions in high-redshift, metal-poor star clusters form very massive stars (VMSs) that can directly collapse to intermediate-mass black holes (IMBHs). We follow the evolution of a pair of neighbouring…
To measure the mass loss from dusty oxygen-rich (O-rich) evolved stars in the Large Magellanic Cloud (LMC), we have constructed a grid of models of spherically-symmetric dust shells around stars with constant mass-loss rates using 2Dust.…
We report an analysis of a sample of 186 spectroscopically confirmed Type II supernova (SN) light curves (LCs) obtained from a combination of Zwicky Transient Facility (ZTF) and Asteroid Terrestrial-impact Last Alert System (ATLAS)…
The formation of a core collapse supernovae (SNe) results in a fast (but non- or mildly-relativistic) shock wave expanding outwards into the surrounding medium. The medium itself is likely modified due to the stellar mass-loss from the…