(Proposal ID) S13A-016

(PI) Hayashi, Masao

(Proposal Title)
Completing comprehensive survey of star formation and metallicity at z~1.5

(Abstract)
We propose to complete our ongoing FMOS program (S12A-026) to comprehensively 
study star formation and metallicity at z~1.5, since two thirds of the time 
allocated in April 2012 was lost because of poor conditions. Star formation 
activity and metal enrichment can provide us with important clues to 
understand processes of galaxy evolution. However, current measurements of 
such properties for galaxies at z~1.5 have large uncertainties and are biased 
toward massive galaxies due to the lack of spectroscopic samples with major 
nebular emission lines in rest-frame optical wavelengths. We thus plan to 
conduct deep NIR spectroscopy of [OII] emitters at z=1.47 and 1.62 in the 
Subaru Deep Field (SDF), aiming to detect all of H beta, [OIII], H alpha, and 
[NII] lines for star-forming galaxies in the epoch when galaxies and AGNs are 
the most active over the cosmic history. The SDF is an ideal field because the 
deep multi-band data are perfectly matched to what FMOS requires for maximum 
efficiency. With the full set of major nebular lines, we will reveal (1) star 
formation activity reliably corrected for dust extinction, (2) gas metallicity,
 and (3) a contribution of AGNs, and investigate a correlation between them. 
We finally aim to understand critical processes which play an important role 
in galaxy evolution.