Hitherto, 21-cm emission has been detected in galaxies only to redshift 0.24, although it is possible to measure the aggregate emission from many more distant, unresolved sources in the 'cosmic web'. Here the authors report a three-dimensional 21-cm intensity field at redshift 0.53–1.12. They co-add neutral-hydrogen emission from the volumes surrounding about 10,000 galaxies to detect the aggregate 21-cm glow at a significance of approximately four standard deviations.
- Tzu-Ching Chang
- Ue-Li Pen
- Jeffrey B. Peterson
