论文标题

Subaru HSC SDS弱透镜Redmapper群集卫星星系:孤儿的经验上限

Subaru HSC weak lensing of SDSS redMaPPer cluster satellite galaxies: Empirical upper limit on orphan fractions

论文作者

Kumar, Amit, More, Surhud, Rana, Divya

论文摘要

弱重力镜头直接探测星系簇中卫星星系周围的物质分布。我们测量了SDSS Redmapper群集卫星星系在背景星系的形状上诱导的弱透镜信号,它们的中央星系为概率$ p _ {\ rm cen}> 0.95 $在Redshift范围内,$ 0.1 \ leq Z \ leq \ leq 0.33 $。为此,我们使用Subaru Hyper Suprime-CAM(HSC)调查的星系形状。我们将卫星星系与群集中心的距离弯曲,并将其与不属于簇但具有相似颜色和大小相似的星系样本的信号进行比较。我们探讨了环境过程对卫星周围暗物质质量的影响。我们看到与对照样品中的星系中的光环质量相比,卫星亚径的质量有所不同,尤其是在以集群为中心的径向箱中($ 0.1 <r <0.3 $ <0.3 $ [$ h^{ - 1} \ rm mpc $])。我们第一次对孤儿星系的患病率提出了上限,孤儿星系的患病率完全以群集为中心的距离借助我们的测量值,完全失去了暗物质光环。但是,如果卫星星系样品中存在实质性污染,这些上限可能会放松。

Weak gravitational lensing directly probes the matter distribution surrounding satellite galaxies in galaxy clusters. We measure the weak lensing signal induced on the shapes of background galaxies around SDSS redMaPPer cluster satellite galaxies, which have their central galaxies assigned with a probability $P_{\rm cen}>0.95$ in the redshift range, $0.1\leq z\leq 0.33$. We use the galaxy shapes from the Subaru Hyper Suprime-Cam (HSC) survey for this purpose. We bin satellite galaxies by their distance from the cluster centre and compare it to the signal around a control sample of galaxies which do not reside in clusters but have similar colours and magnitudes. We explore the effect of environmental processes on the dark matter mass around satellites. We see hints of a difference in the mass of the subhalo of the satellite compared to the halo masses of galaxies in our control sample, especially in the innermost cluster-centric radial bin ($0.1<r<0.3$ [$h^{-1}\rm Mpc$]). For the first time, we put an upper limit on the prevalence of orphan galaxies which have entirely lost their dark matter halos with cluster-centric distances with the help of our measurements. However, these upper limits could be relaxed if there is substantial contamination in the satellite galaxy sample.

扫码加入交流群

加入微信交流群

微信交流群二维码

扫码加入学术交流群,获取更多资源