Super Nova - Current Models - Progenitor


The supernova classification type is closely tied to the type of star at the time of the explosion. The occurrence of each type of supernova depends dramatically on the metallicity and hence the age of the host galaxy.

Type Ia supernovae are produced from white dwarf stars in binary systems and occur in all galaxy types. Core collapse supernovae are only found in galaxies undergoing current or very recent star formation, since they result from short-lived massive stars. They are most commonly found in type Sc spirals, but also in the arms of other spiral galaxies and in irregular galaxies, especially starburst galaxies.

Type Ib/c and II-L, and possibly most type IIn, supernovae are only thought to be produced from stars having near-solar metallicity levels that result in high mass loss from massive stars, hence they are less common in older more distant galaxies. The table shows the expected progenitor for the main types of core collapse supernova, and the approximate proportions of each in the local neighbourhood.

Fraction of core collapse supernovae types by progenitor
Type Progenitor star Fraction
Ib WC Wolf-Rayet 10%
Ic WO Wolf-Rayet 10%
II-P Supergiant 70%
II-L Supergiant with a depleted hydrogen shell 10%
IIn Supergiant in a dense cloud of expelled material (such as LBV) low
IIb Supergiant with highly depleted hydrogen (stripped by companion?) low

There are a number of difficulties reconciling modelled and observed stellar evolution leading up to core collapse supernovae. Red supergiants are the expected progenitors for the vast majority of core collapse supernovae, and these have been observed but only at relatively low masses. It is now proposed that higher mass red supergiants do not explode as supernovae, but instead evolve back to blue supergiants.

Until just a few decades ago, hot supergiants were not considered likely to explode, but observations have shown otherwise. Blue supergiants form a high proportion of confirmed supernova progenitors, partly due to their high luminosity, while not a single Wolf Rayet progenitor has yet been confirmed. The expected progenitors of type Ib supernovae, luminous WC stars, are not observed at all. Instead WC stars are found at lower luminosities, apparently post-red supergiant stars. WO stars are extremely rare and visually relatively faint, so it is difficult to say whether such progenitors are missing or just yet to be observed.

Models have had difficulty showing how blue supergiants lose enough mass to reach supernova without progressing to a different evolutionary stage. One study has shown a possible route for low-luminosity post-red supergiant luminous blue variables to collapse, most likely as a type IIn supernova. Very recently, a small number of yellow supergiant supernova progenitors have been detected. Again these are difficult to explain, requiring unexpectedly high mass loss rates.

Read more about this topic:  Super Nova, Current Models

Other articles related to "progenitor":

SN 2003gd - Progenitor
... SN 2003gd, and which is believed to be the supernova's progenitor star ... This progenitor star was a red supergiant, consistent with the expectations of existing single-star stellar evolution models ... It is the first progenitor of a normal type II-P supernova to have ever been detected ...
Progenitor Cell - Development of The Human Cerebral Cortices
... Before E40 (embryonic day 40), progenitor cells generate other progenitor cells after that period, progenitor cells produce only dissimilar daughters ... The cells from a single progenitor cell form a proliferative unit that creates one cortical column these columns contain a variety of neurons with different shapes ...
Legendary Progenitors - Asia
... Brahma is also mentioned as the progenitor of Manu ... Nyatri Tsenpo was a legendary progenitor of the so-called "Yarlung dynasty" of kings in Tibet ... In Tibet, the term is also connected with a spiritual progenitor ...
The Root of The People Called Sizang and Vaiphei
... Siyin regarded Pu Thuantak as the direct progenitor of the Siyin and Vaiphei ... Tonhing (or Thanhing/Chonhring/Tonring) progenitor of the Buite or Berhvate (progenitor of the Jomsing, Thuksuang, Faihriem, Khawlhring, Vangsia or Vangchhia etc ... It was believed to have been named after their progenitor "Vaiphei", considered to have been the son of Zahong, from whom they claimed their descent ...
... The myeloid progenitor can differentiate in the bone marrow into granulocytes, macrophages (mature monocytes), mast cells (whose blood-borne progenitor is not well defined), and ... In this process it first transforms from a common myeloblast (myeloid progenitor) to a common promyelocyte ... can be classified as an eosinophil, basophil, or neutrophil progenitor based on the histological staining affinity (eosinophilic, basophilic, or neutral granules) ...