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تسجيل مستخدم جديدThe clustering of luminous red galaxies at z $sim$ 0.7 from eBOSS and BOSS data
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We present the first scientific results from the luminous red galaxy sample (LRG) of the extended Baryon Oscillation Spectroscopic Survey (eBOSS). We measure the small and intermediate scale clustering from a sample of more than 61,000 galaxies in the redshift range $0.6 < z < 0.9$. We interpret these measurements in the framework of the Halo Occupation Distribution. The bias of eBOSS LRGs is $2.30 pm 0.03$, with a satellite fraction of $13pm3$% and a mean halo mass of $2.5times10^{13}h^{-1}M_{odot}$. These results are consistent with expectations, demonstrating that eBOSS galaxies will be reliable tracers of large scale structure at $zsim 0.7$. The eBOSS galaxy bias implies a scatter of luminosity at fixed halo mass, $sigma_{log L}$, of 0.19 dex. Using the clustering of massive galaxies from BOSS-CMASS, BOSS-LOWZ, and SDSS, we find that $sigma_{log L}=0.19$ is consistent with observations over the full redshift range that these samples cover. The addition of eBOSS to previous surveys allows investigation of the evolution of massive galaxies over the past $sim 7$ Gyr.
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