The SKA Galactic Centre Survey -- A White Paper

TL;DR

This white paper advocates for a comprehensive, multi-wavelength survey of the Galactic Centre using the Square Kilometre Array, aiming to study extreme galactic environments, star formation, and compact objects with unprecedented detail.

Contribution

It proposes a large-area, repeated, deep radio survey of the Galactic Centre with SKA to enable new insights into galactic nuclei and star formation processes.

Findings

Potential to resolve structures at milli parsec scales.

Facilitates study of rare objects like massive stars and remnants.

Enables long-term monitoring of the nuclear star cluster.

Abstract

With its extreme density of stars and stellar remnants, dense young massive clusters, high specific star formation rate, intense radiation field, high magnetic field strength, and properties of the interstellar medium that resemble those in high redshift galaxies and starbursts, the Galactic Centre is the most extreme environment that we can observe in detail. It is also the only nucleus of a galaxy that we can observe with a resolution of just a few milli parsecs. This makes it a crucial target to understand the physics of galactic nuclei and star formation, as well as the connection between them. It enables studies of a large number of otherwise rare objects, such as extremely massive stars and stellar remnants, at a well-defined distance, thus facilitating the interpretation of their properties. The Galactic Centre has been and is being studied intensively with the most advanced facilities. In this White Paper, we advocate for a large-area, multi-wavelength survey with the Square Kilometre Array of an area of about 1.25x0.3 deg**2 (180x40 pc**2), centered on the massive black hole Sagittarius A* and for repeated deep observations of the nuclear star cluster over a decade, which will allow the community to address multiple science problems with a single data set.