Abstract

The Hydrogen Epoch of Reionization Array (HERA), currently under construction, is a staged project that uses the unique properties of the 21-cm line from neutral hydrogen to probe the Epoch of Reionization (EoR) and the preceding Dark Ages. During these epochs, roughly 0.3-1Gyr after the Big Bang, the first stars and black holes heat and reionize the Universe following cosmic recombination. Direct observation of the large scale structure of reionization and its evolution with time will have a profound impact on our understanding of the birth of the first galaxies and black holes, their influence on the intergalactic medium (IGM), and cosmology. Detecting, characterising and ultimately imaging this epoch is a key goal for the community and was the top priority in the recent US National Science Foundation decadal astronomy survey. Current projects (PAPER, MWA , LOFAR) are striving to make the first detection of the statistical power spectrum of the signal, but current best limits still fall above even optimistic predictions of its intrinsic strength. It is recognised that an optimised array based on our new understanding of the signal characteristics is needed to make a strong detection and begin to characterise this signal over multiple scales and redshifts. HERA is a collaboration responding to this need and intends to deploy in a timeframe useful in providing data to aid SKA optimisation for EOR science. HERA will have a staged deployment of 14-metre antennas in a close-packed hexagonal configuration to maximise sensitivity in the EoR “window”. It is currently under construction in the South African SKA site in the Karoo where PAPER is currently deployed. This talk will provide an overview.