A kinematic confirmation of the hidden Vela supercluster

TL;DR

This study provides the first kinematic evidence of the Vela supercluster behind the Zone of Avoidance using galaxy peculiar velocities, highlighting the need for future detailed surveys of this hidden large-scale structure.

Contribution

It applies two independent techniques to galaxy peculiar velocity data to confirm the existence of the Vela supercluster, a major mass concentration previously unconfirmed by kinematic methods.

Findings

Kinematic signature of the Vela supercluster detected.

Excellent agreement between velocity and density contrast fields.

Highlights the importance of future surveys in the Zone of Avoidance.

Abstract

The universe region obscured by the Milky Way is very large and only future blind large HI redshift, and targeted peculiar surveys on the outer borders will determine how much mass is hidden there. Meanwhile, we apply for the first time two independent techniques to the galaxy peculiar velocity catalog $CosmicFlows-3$ in order to explore for the kinematic signature of a specific large-scale structure hidden behind this zone : the Vela supercluster at cz $\sim 18,000$,km s$^{-1}$ . Using the gravitational velocity and density contrast fields, we find excellent agreement when comparing our results to the Vela object as traced in redshift space. The article provides the first kinematic evidence of a major mass concentration (knot of the Cosmic Web) located in the direction behind Vela constellation, pin-pointing that the Zone of Avoidance should be surveyed in detail in the future .