论文标题
宇宙网络中的细丝有多黑？
How dark are filaments in the cosmic web?
论文作者
论文摘要
冷暗物质模型预测，暗物质光环通过细丝连接。这些细丝的质量和结构的直接测量很困难，但是最近有一些研究使用弱透镜检测到了这些以暗遗物为主的细丝。在这里，我们通过测量其总质量比和恒星质量分数来研究银河系形成的效率。具体而言，我们堆叠成对的发光红星系（LRGS），在$ 8 H^{ - 1} $ MPC上的典型分离。我们在对周围堆叠背景星系形状，以通过弱透镜获得质量图，并从斯隆数字天空调查（SDSS）中堆叠星系，以获取光和恒星质量的地图。为了隔离灯丝的信号，我们构建了两个匹配的物理和非物理（投影）LRG对的目录，具有相同的红移和分离分布。然后，我们减去两个堆叠的地图。使用来自Boss调查的LRG对样品在两个不同的红移中，我们发现细丝中质量的演变与扰动理论的预测一致。细丝并非完全黑：它们的质量比（$ m/l = 351 \ pm137 $ in $ r $ - band中的太阳能单元）和恒星质量分数（$ m _ {\ rm _ {\ rm stellar}/m = 0.0073 \ pm0.0030 $）与他们的cosmic值一致，并且与他们的cosmic值一致（
The cold dark matter model predicts that dark matter haloes are connected by filaments. Direct measurements of the masses and structure of these filaments are difficult, but recently several studies have detected these dark-matter-dominated filaments using weak lensing. Here we study the efficiency of galaxy formation within the filaments by measuring their total mass-to-light ratios and stellar mass fractions. Specifically, we stack pairs of Luminous Red Galaxies (LRGs) with a typical separation on the sky of $8 h^{-1}$ Mpc. We stack background galaxy shapes around pairs to obtain mass maps through weak lensing, and we stack galaxies from the Sloan Digital Sky Survey (SDSS) to obtain maps of light and stellar mass. To isolate the signal from the filament, we construct two matched catalogues of physical and non-physical (projected) LRG pairs, with the same distributions of redshift and separation. We then subtract the two stacked maps. Using LRG pair samples from the BOSS survey at two different redshifts, we find that the evolution of the mass in filament is consistent with the predictions from perturbation theory. The filaments are not entirely dark: their mass-to-light ratios ($M/L = 351\pm137$ in solar units in the $r$-band) and stellar mass fractions ($M_{\rm stellar}/M = 0.0073\pm0.0030$) are consistent with the cosmic values (and with their redshift evolutions)
