PI: Dario Fadda, Spitzer Science Center - Caltech, email@example.com
Address: PMA, Mail Code 220-6, Pasadena, CA 91125, USA
CoI: Francine Marleau, Spitzer Science Center - Caltech
CoI: Lisa Storrie-Lombardi, Spitzer Science Center - Caltech
CoI: Andrea Biviano, INAF-Trieste (Italy)
CoI: Florence Durret, IAP (France)
Title: Star Formation in Medium-z Clusters: a Search for Infalling Galaxies beyond the Virial Radius.
Abstract: As infalling galaxies encounter the dense cluster environment, their evolution is dramatically accelerated. Our current understanding of this process is limited to the later stages of the galaxy-cluster interaction and to a partial view of the star formation activity (unobscured by dust). Far-IR observations are the most efficient way to select star-forming galaxies obscured by dust. We have recently observed three medium-z clusters with the Spitzer Space Telescope (IRAC and MIPS instruments) out to three virial radii. We propose to obtain spectra for all the galaxies brighter than 0.5mJy at 24(micron) (roughly corresponding to a star formation rate of 2-3 M_\odotyr^-1) with optical counterparts brighter than r'=20.5. These observations, coupled with optical spectroscopy, will provide an unbiased estimate of the star formation in cluster of galaxies and a better understanding of the role of the environment in stimulating/quenching the star formation of infalling galaxies. The WIYN/Hydra spectrograph with its large field of view and high number of fibers is the ideal instrument for this study.
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