New simulation of QSO X-ray heating during the Cosmic Dawn
Abstract
The upcoming radio interferometer Square Kilometre Array is expected to directly detect the redshifted 21-cm signal from the Cosmic Dawn for the first time. In this era temperature fluctuations from X-ray heating of the neutral intergalactic medium can impact this signal dramatically. Previously, in Ross et al. (2017), we presented the first large-volume, 244 h-1 Mpc=349 Mpc a side, fully numerical radiative transfer simulations of X-ray heating. This work is a follow-up where we now also consider QSO-like sources in addition to high mass X-ray binaries. Images of the two cases are clearly distinguishable at SKA1-LOW resolution and have RMS fluctuations above the expected noise. The inclusion of QSOs leads to a dramatic increase in non-Gaussianity of the signal, as measured by the skewness and kurtosis of the 21-cm signal. We conclude that this increased non-Gaussianity is a promising signature of early QSOs.
- Publication:
-
Peering towards Cosmic Dawn
- Pub Date:
- May 2018
- DOI:
- 10.1017/S1743921317011115
- arXiv:
- arXiv:1801.06527
- Bibcode:
- 2018IAUS..333...34R
- Keywords:
-
- cosmology: theory;
- radiative transfer;
- reionization;
- intergalactic medium;
- large-scale structure of universe;
- galaxies: formation;
- QSOs;
- Astrophysics - Cosmology and Nongalactic Astrophysics
- E-Print:
- 5 pages, 2 figures, Proceedings IAU Symposium No. 333, 2018