Luminous infrared starbursts in a cluster of galaxies

Analysing mid-infrared ISOCAM images of the cluster of galaxies J1888.16CL, we identified among its members several particularly active galaxies with total infrared luminosities well above 10¹¹ Lo. If powered by dust enshrouded starbursts, as suggested by their optical spectra, these Luminous Infrared Galaxies would exhibit star formation rates surprisingly high in the cluster environment. The triggering mechanism is unclear but could be tidal collisions within sub-structures or infalling groups.