A Luminous Infrared Galaxy (LIRG) is a Galaxy
emitting more than 1011 times solar Luminosity
in the Far Infrared.
They are often a Starburst Galaxy and/or have an
Active Galactic Nucleus or a Quasar.
Hyperluminous Infrared Galaxy (HLIRG)
Ultraluminous Infrared Galaxy (ULIRG)