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Type IIP supernovae (SNe IIP) are thought to originate from the explosion of massive stars >10 M _⊙ . Their luminosity is primarily powered by the explosion energy and the radioactive decay energy of ^56 Co, with the photosphere location regulated by hydrogen recombination. However, the physical connections between SNe IIP and their progenitor stars remain unclear. This paper presents a comprehensive study of SNe IIP and their progenitor stars by using the one-dimensional stellar evolution code, MESA . Our model grids consider the effects of stellar metallicity, mass, and rotation in the evolution of massive stars, as well as the explosion energy and ^56 Ni production in modeling supernovae. To elucidate the observed SNe IIP and their origins, we compare their light curves (LCs) with our models. Furthermore, we investigate the impact of stellar parameters on LCs by considering stellar mass, metallicity, rotation, explosion energy, and ^56 Ni production. We find that more massive stars exhibit longer plateaus due to increased photon diffusion time caused by massive ejecta. Higher metallicity leads to increased opacity and mass loss of progenitor stars. Rapid rotation affects internal stellar structures, enhancing convective mixing and mass loss, potentially affecting the plateau’s brightness and duration. Higher explosion energy results in brighter but shorter plateaus due to faster-moving ejecta. ^56 Ni mass affects late-time luminosity and plateau duration, with larger masses leading to slower declines.

Supergiant shells (SGSs) are the largest interstellar structures where heated and enriched gas flows into the host galaxy’s halo. The SGSs in the Large Magellanic Cloud (LMC) are so close that their stars can be resolved with ground-based telescopes to allow studies of star-formation history. Aiming to study the star formation history and energy budget of LMC 4, we have conducted a pilot study of the cluster NGC 2021 and the OB associations in its vicinity near the south rim of LMC 4. We use the Magellanic Cloud Photometric Survey data of the LMC to establish a methodology to examine the stellar population and assess the massive star formation history. We find a radial procession of massive star formation from the northwest part of the OB association LH79 through NGC 2021 to the OB association LH78 in the south. Using the stellar content of NGC 2021 and the assumption of Salpeter’s initial mass function, we estimate that ∼4 supernovae have occurred in NGC 2021, injecting at least 4 × 10 ^51 erg of kinetic energy into the interior of LMC 4.

Massive Population III stars can die as energetic supernovae that enrich the early Universe with metals and determine the properties of the first galaxies. With masses of about 10 ^9 M _⊙ at z ≳ 10, these galaxies are believed to be the ancestors of the Milky Way. This paper investigates the impact of Population III supernova remnants (SNRs) from both Salpeter-like and top-heavy initial mass functions (IMFs) on the formation of first galaxies with high-resolution radiation-hydrodynamical simulations with the ENZO code. Our findings indicate that SNRs from a top-heavy Population III IMF produce more metals, leading to more efficient gas cooling and earlier Population II star formation in the first galaxies. From a few hundred to a few thousand Population II stars can form in the central regions of these galaxies. These stars have metallicities of 10 ^−3 –10 ^−2 , Z _⊙ , greater than those of extremely metal-poor (EMP) stars. Their mass function follows a power-law distribution with ${dN}({M}_{* })/{{dM}}_{* }\propto {M}_{* }^{\alpha }$ , where M _* is stellar mass, and α = 2.66–5.83 and is steeper for a top-heavy IMF. We thus find that EMP stars were not typical of most primitive galaxies.

Numerical simulations have now shown that Population III (Pop III) stars can form in binaries and small clusters and that these stars can be in close proximity to each other. If so, they could be subject to binary interactions such as mass exchange that could profoundly alter their evolution, ionizing UV and Lyman–Werner photon emission and explosion yields, with important consequences for early cosmological reionization and chemical enrichment. Here we investigate the evolution of Pop III and extremely metal-poor binary stars with the MESA code. We find that interactions ranging from stable mass transfer to common envelope evolution can occur in these binaries for a wide range of mass ratios and initial separations. Mass transfer can nearly double UV photon yields in some of these binaries with respect to their individual stars by extending the life of the companion star, which in turn can enhance early cosmological reionization but also suppress the formation of later generations of primordial stars. Binary interactions can also have large effects on the nucleosynthetic yields of the stars by promoting or removing them into or out of mass ranges for specific SN types. We provide fits to total photon yields for the binaries in our study for use in cosmological simulations.

This paper systematically studies the relation between metallicity and mass loss of massive stars. We perform one-dimensional stellar evolution simulations and build a grid of ∼2000 models with initial masses ranging between 11 and 60 M _⊙ and absolute metallicities Z between 0.00001 and 0.02. Steady-state winds, comprising hot main-sequence winds and cool supergiant winds, are the main drivers of the mass loss of massive stars in our models. We calculate the total mass loss over the stellar lifetime for each model. Our results reveal the existence of a critical metallicity Z _c at Z ∼ 10 ^−3 , where the mass loss exhibits a dramatic jump. If Z > Z _c , massive stars tend to evolve into cool supergiants, and a robust cool wind is operational. In contrast, if Z < Z _c , massive stars usually remain as blue supergiants, wherein the cool wind is not activated and the mass loss is generally weak. Moreover, we calculate the wind feedback in a 10 ^5 M _⊙ star cluster with the Salpeter initial mass function. The kinetic energy released by winds does not exhibit any significant transition at Z _c because the wind velocity of a cool supergiant wind is low and contributes little to the kinetic energy. The effects of critical metallicity provide implications for the fates of metal-poor stars in the early universe.

The Large Magellanic Cloud (LMC) has ∼60 confirmed supernova remnants (SNRs). Because of the known distance, 50 kpc, the SNRs’ angular sizes can be converted to linear sizes, and their X-ray observations can be used to assess X-ray luminosities (LX). We have critically examined the LMC SNRs’ sizes reported in the literature to determine the most plausible sizes. These sizes and the LX determined from XMM-Newton observations are used to investigate their relationship to explore the environmental and evolutionary effects on the X-ray properties of SNRs. Our research provides the following three results. (1) Small LMC SNRs, a few to 10 pc in size, are all Type Ia with LX > 1036 erg s−1. The scarcity of small core-collapse (CC) SNRs is a result of CC SNe exploding in the low-density interiors of interstellar bubbles blown by their massive progenitors during their main-sequence phase. (2) Medium-sized (10–30 pc) CC SNRs show bifurcation in LX, with the X-ray-bright SNRs either in an environment associated with molecular clouds or containing pulsars and pulsar-wind nebulae and the X-ray-faint SNRs being located in low-density interstellar environments. (3) Large (size > 30 pc) SNRs show a trend of LX fading with size, although the scatter is large. The observed relationship between LX and sizes can help constrain models of SNR evolution. [ABSTRACT FROM AUTHOR]