相关论文: Constraining red supergiant mass-loss prescription…

Type IIP (plateau) supernovae are thought to come from stars with initial mass about 8-25 solar masses that end their lives as red supergiants. The expected stellar end points can be found from evolutionary calculations and the…

Mass loss of red supergiants (RSG) is important for the evolution of massive stars, but is not fully explained. Several empirical prescriptions have been proposed, trying to express the mass-loss rate (Mdot) as a function of fundamental…

The mass loss mechanism of red supergiant stars is not well understood, even though it has crucial consequences for their stellar evolution and the appearance of supernovae that occur upon core-collapse. We argue that outgoing shock waves…

Mass loss of massive helium stars is not well understood even though it plays an essential role in determining their remnant neutron-star or black-hole masses as well as ejecta mass of Type Ibc supernovae. Radio emission from Type Ibc…

The fate of massive stars with initial masses >8M$_\odot$ depends largely on the mass-loss rate (\mdot ) in the end stages of their lives. Red supergiants (RSGs) are the direct progenitors to Type II-P core collapse supernovae (SN), but…

We present VLA observations of 16 Type IIn and Type II-L supernovae (SNe IIn and SNe II-L) at ~1000--7000 days after explosion, probing circumstellar matter (CSM) at distances >10^16 cm from the progenitor corresponding to mass-loss over…

I review existing methods for determining mass-loss rates of red giants and red supergiants based on infrared data. The simplest method is based on models for the absorption and emission by dust which forms in the dense outflows from these…

We report mid- to far-infrared imaging and photomety from 7 to 37 microns with SOFIA/FORCAST and 2 micron adaptive optics imaging with LBTI/LMIRCam of a large sample of red supergiants (RSGs) in four Galactic clusters; RSGC1,…

Mass-loss in red supergiants (RSGs) is generally recognized to be episodic, but mass-loss prescriptions fail to reflect this. Evolutionary models show that the total amount of mass lost during this phase determines if these stars evolve to…

In this work we study the circumstellar material (CSM) around massive stars, and the mass-loss rates depositing this CSM, using a large sample of radio observations of 325 core-collapse supernovae (CCSNe; only $\sim 22 \%$ of them being…

We investigate the diversity in the wind density, supernova ejecta energy, and ejecta mass in Type IIn supernovae based on their rise times and peak luminosities. We show that the wind density and supernova ejecta properties can be…

The red supergiant (RSG) problem refers to the observed dearth of luminous RSGs identified as progenitors of Type II supernovae (SNe II) in pre-SN imaging. Understanding this phenomenon is essential for studying pre-SN mass loss and the…

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…

This review discusses the causes, nature, importance and observational evidence of mass loss by red supergiants. It arrives at the perception that mass loss finds its origin in the gravity which makes the star a star in the first place, and…

The inevitable fate of massive stars in the initial mass range of ~8--30 M_{Sun} in the red supergiant (RSG) phase is a core-collapse supernova (SN) explosion, although some stars may collapse directly to a black hole. We know that this is…

We present results of a systematic study of the mass-loss properties of Type IIn supernova progenitors within decades before their explosion. We apply an analytic light curve model to 11 Type IIn supernova bolometric light curves to derive…

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…

Supernovae characterized by enduring narrow optical hydrogen emission lines (SNe IIn) are believed to result primarily from the core-collapse of massive stars undergoing sustained interaction with a dense circumstellar medium (CSM). While…

The increasing observed number of supernova events allows for finding ever more frequently the progenitor star in archive images. In a few cases, the progenitor star is a yellow supergiant star. The estimated position in the…

We assemble a large set of 2-10 GHz radio flux density measurements and upper limits of 294 different supernovae (SNe), from the literature and our own and archival data. Only 31% of the SNe were detected. We characterize the SN lightcurves…