Jet Cocoon Definition

noun

A cloud of gas that obscures the poles of a star undergoing hypernova (HN), which gets heated by the polar jet escaping the hypernova progenitor star (hnp), and may absorb the energy of a weak gamma-ray burst (GRB), leaving an observable HN lacking the associated GRB, or be penetrated by a stronger GRB, giving a HN with an associated GRB.

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