A direct detection of neutral hydrogen intensity mapping on Mpc scales at $zapprox 0.32$ and $zapprox 0.44$
Sourabh Paul, Zhaoting Chen, Mario G. Santos, Laura Wolz
arXiv:2301.11943v2 Announce Type: replace
Abstract: We report the detection of the cosmological power spectrum using the intensity mapping signal from 21-cm emission of neutral hydrogen (HI), derived from interferometric observations with the L-band receivers of the MeerKAT radio telescope. Intensity mapping is a promising technique to map the three-dimensional matter distribution of the Universe at radio frequencies and probe the underlying Cosmology. So far, detections have only been achieved through cross-correlations with galaxy surveys. Here we present independent measurements of the HI power spectrum at redshifts $0.32$ and $0.44$ with the foreground avoidance method. We utilize two distinct frameworks for mitigating systematics, where a conservative baseline flagging based approach achieves detections at $3.2sigma$ and $3.5sigma$, and a power spectrum based flagging method enhances the significance to $5.9sigma$ and $9.18sigma$, respectively. The information contained in the power spectrum measurements allows us to probe the parameters of the HI mass function and HI halo model. These results are a significant step towards precision cosmology with HI intensity mapping using the new generation of radio telescopes.arXiv:2301.11943v2 Announce Type: replace
Abstract: We report the detection of the cosmological power spectrum using the intensity mapping signal from 21-cm emission of neutral hydrogen (HI), derived from interferometric observations with the L-band receivers of the MeerKAT radio telescope. Intensity mapping is a promising technique to map the three-dimensional matter distribution of the Universe at radio frequencies and probe the underlying Cosmology. So far, detections have only been achieved through cross-correlations with galaxy surveys. Here we present independent measurements of the HI power spectrum at redshifts $0.32$ and $0.44$ with the foreground avoidance method. We utilize two distinct frameworks for mitigating systematics, where a conservative baseline flagging based approach achieves detections at $3.2sigma$ and $3.5sigma$, and a power spectrum based flagging method enhances the significance to $5.9sigma$ and $9.18sigma$, respectively. The information contained in the power spectrum measurements allows us to probe the parameters of the HI mass function and HI halo model. These results are a significant step towards precision cosmology with HI intensity mapping using the new generation of radio telescopes.

Comments are closed, but trackbacks and pingbacks are open.