| Description |
On the extragalactic side, one of the most remarkable results comingout of Herschel is the discovery of extremely bright (>100 mJy in theSPIRE bands) gravitationally lensed galaxies. The great sensitivityand mapping speed of SPIRE have enabled us to find these rareextraordinary objects. What is truly exciting about these brightlensed galaxies is that they enable a variety of detailedmulti-wavelength follow-up observations, shedding new light on thephysical properties of these high-redshift sources. In this regard,our OT1 program, SPIRE Snapshot Survey of Massive Galaxy Clustersturned out to be a great success. After imaging ~50 galaxies out of279 in the program, we have already found two spectacularly brightlensed galaxies, one of which is at a redshift of 4.69. This type ofcluster-lensed sources are not only bright but also spatiallystretched over a large scale, so ALMA (or NOEMA in the north) islikely to be able to study them at the level of individual GMCs. Suchstudies will open up a new frontier in the study of high-redshiftgalaxies.Here, we propose to extend this highly efficient and effective surveyof gravitationally lensed galaxies to another 353 clusters carefullychosen from the SPT and CODEX cluster samples. These samples containnewly discovered high-redshift (z>0.3) massive (>3-4e14 Msun)clusters, which can be used as powerful gravitational lenses tomagnify sources at high redshift. With the OT1 and OT2 surveystogether, we expect to find ~20 highly magnified SPIRE sources withexceptional brightnesses (assuming a discovery rate of ~1/30). Such aunique sample of extraordinary objects will enable a variety offollow-up sciences, and will therefore remain as a great legacy of theHerschel mission for years to come. |
