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GalWeight Application: A publicly-available catalog of dynamical parameters of 1,800 galaxy clusters from SDSS-DR13, ($mathtt{GalWCat19}$)

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 نشر من قبل Mohamed Abdullah
 تاريخ النشر 2019
  مجال البحث فيزياء
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Utilizing the SDSS-DR13 spectroscopic dataset, we create a new publicly-available catalog of 1,800 galaxy clusters (GalWeight cluster catalog, $mathtt{GalWCat19}$) and a corresponding catalog of 34,471 identified member galaxies. The clusters are identified from overdensities in redshift-phase space. The GalWeight technique introduced in Abdullah, Wilson and Klypin (AWK18) is then applied to identify cluster members. The completeness of the cluster catalog ($mathtt{GalWCat19}$) and the procedure followed to determine cluster mass are tested on the Bolshoi N-body simulations. The 1,800 $mathtt{GalWCat19}$ clusters range in redshift between $0.01 - 0.2$ and in mass between $(0.4 - 14) times 10^{14}h^{-1}M_{odot}$. The cluster catalog provides a large number of cluster parameters including sky position, redshift, membership, velocity dispersion, and mass at overdensities $Delta = 500, 200, 100, 5.5$. The 34,471 member galaxies are identified within the radius at which the density is 200 times the critical density of the Universe. The galaxy catalog provides the coordinates of each galaxy and the ID of the cluster that the galaxy belongs to. The cluster velocity dispersion scales with mass as $log(sigma_{200})=log(946pm52~ mbox{km} ~ mbox{s}^{-1}) +(0.349pm0.142)logleft[h(z) ~ M_{200}/10^{15}M_odotright]$ with scatter of $delta_{logsigma} = 0.06$. The catalogs are publicly available at the following websitefootnote{url{https://mohamed-elhashash-94.webself.net/galwcat/}}.


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