collapsar

noun

col·​lap·​sar

kə-ˈlap-ˌsär

plural collapsars

: a massive star that undergoes gravitational collapse especially after colliding with another star

Collapsars are massive stars, which in the course of merging with a compact companion undergo core collapse leading to a BH [black hole] … leaving a supernova-like remnant.

—P. Mészáros, Science, 5 Jan. 2001

Today most astronomers think gamma-ray bursts result when a massive and rapidly rotating star collapses in on itself to form a black hole. The collapsing star, or collapsar, is a kind of supernova, but the extraordinary heft and spin of the star bring it to a faster and more calamitous end.

—Karen Wright, Discover, August 2002

broadly : black hole sense 2

This classification of stars results in three main types: regular stars (covering white dwarfs to super-giants) …, neutron stars and pulsars, … and collapsars (i.e. black holes) … .

—Pierre A. Millette, Progress in Physics, January 2014

Word History

Etymology

collapse entry 1 + -ar (as in quasar)

First Known Use

1971, in the meaning defined above

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