title: Afterglows from the largest explosions in the universe.
abstract: The distinction of "largest explosions in the universe" has been bestowed on cosmic gamma-ray bursts. Their afterglows are brighter than supernovae and therefore are called hypernovae. Photometry and spectroscopy of these afterglows have provided major breakthroughs in our understanding of this mysterious phenomenon.
authors.affiliation: Department of Physics and Astronomy, Clemson University, Clemson, SC 29634-1911, USA.
authors.forename: D H
authors.initials: DH
authors.lastname: Hartmann