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We present basic properties of $sim$3,300 emission line galaxies detected by the FastSound survey, which are mostly H$alpha$ emitters at $z sim$ 1.2-1.5 in the total area of about 20 deg$^2$, with the H$alpha$ flux sensitivity limit of $sim 1.6 times 10^{-16} rm erg cm^{-2} s^{-1}$ at 4.5 sigma. This paper presents the catalogs of the FastSound emission lines and galaxies, which will be open to the public in the near future. We also present basic properties of typical FastSound H$alpha$ emitters, which have H$alpha$ luminosities of $10^{41.8}$-$10^{43.3}$ erg/s, SFRs of 20--500 $M_odot$/yr, and stellar masses of $10^{10.0}$--$10^{11.3}$ $M_odot$. The 3D distribution maps for the four fields of CFHTLS W1--4 are presented, clearly showing large scale clustering of galaxies at the scale of $sim$ 100--600 comoving Mpc. Based on 1,105 galaxies with detections of multiple emission lines, we estimate that contamination of non-H$alpha$ lines is about 4% in the single-line emission galaxies, which are mostly [OIII]$lambda$5007. This contamination fraction is also confirmed by the stacked spectrum of all the FastSound spectra, in which H$alpha$, [NII]$lambda lambda$6548,6583, [SII]$lambda lambda$6717, 6731, and [OI]$lambda lambda$6300,6364 are seen.
The growth rate of matter density perturbations has been measured from redshift-space distortion (RSD) in the galaxy power spectrum. We constrain the model parameter space for representative modified gravity models to explain the dark energy problem, by using the recent data of f_m(z)sigma_8(z) at the redshifts z = 0.06--0.8 measured by WiggleZ, SDSS LRG, BOSS, and 6dFGRS. We first test the Hu-Sawickis f(R) dark energy model, and find that only the parameter region close to the standard Lambda Cold Dark Matter (Lambda-CDM) model is allowed (lambda > 12 and 5 for n = 1.5 and 2, respectively, at 95% CL). We then investigate the covariant Galileon model and show that the parameter space consistent with the background expansion history is excluded by the RSD data at more than 10 sigma because of the too large growth rate predicted by the theory. Finally, we consider the extended Galileon scenario, and we find that, in contrast to the covariant Galileon, there is a model parameter space for a tracker solution that is consistent with the RSD data within a 2 sigma level.
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