We present a new SCUBA image of the cluster MS 0451.6 - 0305 , which exhibits strong , extended sub-mm flux at 850 \mu m. The most striking feature in the map is an elongated region of bright sub-mm emission , with a flux density of { \sim } 10 mJy over several beam-sizes .
This region is apparently coincident with a previously known optical arc ( which turns out to be a strongly lensed Lyman Break Galaxy at z = 2.911 ) , as well as with a newly identified multiply imaged ERO ( Extremely Red Object ) pair predicted to be at a similar , if not identical redshift .
By combing a detailed lensing model with deep images from HST , Chandra , CFHT , JCMT , and spectra from the VLT , we conclude that both the strongly lensed optical arc and ERO systems have properties consistent with known sub-mm emitters .
Using a simple model for the two sources , we estimate that the multiply lensed EROs contribute the majority of the flux in the SCUBA lensed arc .
Correcting for the lensing amplification , we estimate that the inherent 850 \mu m fluxes for both objects are _ { < } \atop { } ^ { \sim } 0.4 mJy .
If the LBG and ERO pair are truly at the same redshift , then they are separated by only \sim 10 kpc in the source plane , and hence constitute an interacting system at z \sim 2.9 .
Higher angular resolution observations in sub-mm/mm will permit us to more accurately separate the contribution from each candidate , and better understand the nature of this system .