Page "Gamma-ray burst" Paragraph 18

Most observed events have a duration of greater than two seconds and are classified as long gamma-ray bursts.

Because these events constitute the majority of the population and because they tend to have the brightest afterglows, they have been studied in much greater detail than their short counterparts.

Almost every well-studied long gamma-ray burst has been linked to a galaxy with rapid star formation, and in many cases to a core-collapse supernova as well, unambiguously associating long GRBs with the deaths of massive stars.

Long GRB afterglow observations, at high redshift, are also consistent with the GRB having originated in star-forming regions.