Like a spider in its web: a study of the Large Scale Structure around
  the Coma cluster
  The Cosmic Web is a complex network of filaments, walls and voids that
represent the largest structures in the Universe. In this network, which is the
direct result of structure formation, galaxy clusters occupy central positions
as the nodes, connected through the filaments. In this work, we investigate the
position in the Cosmic Web of one of the most known and best studied clusters
of galaxies, the Coma cluster. We make use of the Sloan Digital Sky Survey Data
Release 7 (SDSS DR7) Main Galaxy Sample and of the Discrete Persistent
Structure Extractor (DisPerSE) to detect large scale filaments around the Coma
cluster and we analyze the properties of the Cosmic Web. We study the network
of filaments around Coma in a 75 Mpc radius region. We find that the Coma
cluster has a median connectivity of 2.5, in agreement with measurements from
clusters of similar mass in the literature, as well as with what expected from
numerical simulations. It is indeed connected to 3 secure filaments which
connect Coma to Abell 1367 and to several other clusters in the field. The
location of these filaments in the vicinity of Coma is consistent with features
detected in the X-ray, as well as the likely direction of infall of galaxies,
as for example NGC 4839. The overall picture that emerges of the Coma cluster
is that of a highly connected structure occupying a central position as a dense
node of the Cosmic Web. We also find a tentative detection, at 2.1$\sigma$
significance, of the filaments in the SZ signal.
