Identification of Superclusters and Their Properties in the Sloan Digital Sky Survey Using the WHL Cluster Catalog

Superclusters are the largest massive structures in the cosmic web. The authors present a large catalog of 662 superclusters identified using a modified Friends-of-Friends (FoF) algorithm applied to the WHL (Wen-Han-Liu) galaxy cluster catalog within 0.05 ≤ z ≤ 0.42. The most massive supercluster at z ≈ 0.25 is newly identified and proposed to be named the Einasto Supercluster. The median supercluster mass is ≈ 5.8 × 10^15 M⊙ and median size ≈ 65 Mpc. The supercluster environment slightly biases cluster growth toward higher masses. Observed supercluster properties are compared with mock superclusters extracted from the Horizon Run 4 simulation and show broad agreement. A power-law correlation is found between density contrast and maximum extent with slope α ≈ −2. Phase-space analysis of mock superclusters indicates that on average ≈ 90% of a supercluster’s volume exerts gravitational influence on its constituents. The study also presents number density and peculiar velocity profiles of mock halos in and around superclusters.

Shishir Sankhyayan, Joydeep Bagchi, Elmo Tempel, Surhud More, Maret Einasto, Pratik Dabhade, Somak Raychaudhury, Ramana Athreya, Pekka Heinämäki