Abstract
We present an unprecedentedly large catalog consisting of 2,354 >~ L^* Lya
emitters (LAEs) at z=5.7 and 6.6 on the 13.8 and 21.2 deg^2 sky, respectively,
that are identified by the SILVERRUSH program with the first narrowband imaging
data of the Hyper Suprime-Cam (HSC) survey. We confirm that the LAE catalog is
reliable on the basis of 97 LAEs whose spectroscopic redshifts are already
determined by this program and the previous studies. This catalogue is also
available on-line. Based on this catalogue, we derive the rest-frame Lya
equivalent-width distributions of LAEs at z=5.7 and 6.6 that are reasonably
explained by the exponential profiles with the scale lengths of 72+/-19 and
119+/-4 A, respectively, showing the increase trend towards high-z. We find
that ~700 LAEs with a large equivalent width (LEW) of >~ 240 A are candidates
of young-metal poor galaxies and AGNs. We also find that the fraction of LEW
LAEs to all ones is moderately large, ~30%. Our LAE catalog includes 11 Lya
blobs (LABs) that are LAEs with spatially extended Lya emission whose profile
is clearly distinguished from those of stellar objects at the >~ 3sigma level.
The number density of the LABs at z=6-7 is ~10^-7-10^-6 Mpc-3, being
~10-100 times lower than those claimed for LABs at z~2-3, suggestive of
disappearing LABs at z>~6, albeit with the different selection methods and
criteria for the low and high-z LABs.
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