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Dissecting the Strong-lensing Galaxy Cluster MS 0440.5+0204. I. The Mass Density Profile

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 نشر من قبل Tomas Verdugo
 تاريخ النشر 2020
  مجال البحث فيزياء
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We present a parametric strong lensing modeling of the galaxy cluster MS,0440.5+0204 (located at $z$ = 0.19). We have performed a strong lensing mass reconstruction of the cluster using three different models. The first model uses the image positions of four multiple imaged systems (providing 26 constraints). The second one combines strong lensing constraints with dynamical information (velocity dispersion) of the cluster. The third one uses the mass calculated from weak lensing as an additional constraint. Our three models reproduce equally well the image positions of the arcs, with a root-mean-square image equal to $approx$0.5$arcsec$. However, in the third model, the inclusion of the velocity dispersion and the weak-lensing mass allows us to obtain better constraints in the scale radius and the line-of-sight velocity dispersion of the mass profile. For this model, we obtain $r_s$ = 132$^{+30}_{-32}$ kpc, $sigma_s$ = 1203$^{+46}_{-47}$ km s$^{-1}$, M$_{200}$ = 3.1$^{+0.6}_{-0.6}$ $times10^{14}$,M$_{odot}$, and a high concentration, $c_{200}$ = 9.9$^{+2.2}_{-1.4}$. Finally, we used our derived mass profile to calculate the mass up to 1.5 Mpc. We compare it with X-ray estimates previously reported, finding a good agreement.

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