kilonova

The term kilonova (KN) was coined in 2010 for a transient that was theorized would be produced by a neutron star merger (NS merger). The term suggests an energy release less than that of a supernova, of roughly a thousand times that of a nova, the amount presumed to occur in such a merger. (The term macronova was earlier coined for such an NS merger.) Much of the EMR from such an event is thought to occur in the infrared, making OIR observation useful. An optical transient (OT) was found at the sky-location of GW170817, which was independently classified as an NS merger due to the GW-detection characteristics, making it the first confirmed kilonova observation.

Models developed for kilonovae have been classified as blue kilonova models versus red kilonova models, the color names used to indicate a shorter versus longer wavelength EMR rather than the actual colors: both deal with peaks in the near infrared. The red models would be producing more lanthanides and the blue, less. GW170817 shows some of each, with "red model" characteristics revealed after "blue model" characteristics had subsided. The term blue kilonova has been used for some observed kilonovae.