Dr Chris Blake (UNSW)

Large-scale structure from radio surveys: present and future - Dr Chris Blake Colloquium

ATNF Marsfield Lecture Theatre

Abstract

Radio galaxies are powerful tracers of the cosmic web, routinely
detectable over wide areas of sky out to very high redshifts, in a
manner impervious to dust extinction. They are beacons to massive
elliptical galaxies, and provide a very clean method of locating
clusters and superclusters in the Universe.

In this talk, I'll present my analysis of the angular patterns of
structure in the NVSS radio survey. On small angular scales (< 1
degree) we can derive the cosmological "clustering length" of radio
galaxies, hence their bias with respect to mass fluctuations. On
large angular scales (180 degrees) we can detect the imprint of the
"cosmic velocity dipole", the fluctuation in source surface density
due to the Earth's peculiar motion with respect to the Cosmic
Microwave Background.

In addition, I'll discuss the large-scale structure science made
possible by the next generation of proposed radio interferometers,
such as HYFAR and the Square Kilometre Array. A large-scale survey of
21cm emission galaxies can map out the 3D galaxy clustering pattern
with unprecedented precision, enabling a battery of powerful
cosmological measurements.