Detecting the relativistic bispectrum in 21cm intensity maps

Sep 14, 2020
18 pages
Published in:
  • JCAP 06 (2021) 039
  • Published: Jun 22, 2021
e-Print:

Citations per year

2020202120222023202401234567
Abstract: (IOP)
We investigate the detectability of leading-order relativistic effects in the bispectrum of future 21cm intensity mapping surveys. The relativistic signal arises from Doppler and other line-of-sight effects in redshift space. In the power spectrum of a single tracer, these effects are suppressed by a factor ℋ2/k2. By contrast, in the bispectrum the relativistic signal couples to short-scale modes, leading to an imaginary contribution that scales as ℋ/k, thus increasing the possibility of detection. Previous work has shown that this relativistic signal is detectable in a Stage IV Hα galaxy survey. We show that the signal is also detectable by next-generation 21cm intensity maps, but typically with a lower signal-to-noise, due to foreground and telescope beam effects.
Note:
  • 18 pages, 12 figures, Version accepted by JCAP
Loading ...