Low-amplitude clustering in low-redshift 21-cm intensity maps cross-correlated with 2dF galaxy densities

  title={Low-amplitude clustering in low-redshift 21-cm intensity maps cross-correlated with 2dF galaxy densities},
  author={Christopher J. Anderson and Nicholas J. Luciw and Y.-C. Li and Cheng-Yu Kuo and Jaswant Kumar Yadav and Kiyoshi W. Masui and T.-C. Chang and X. Chen and Niels Oppermann and Yu-Wei Liao and Ue-li Pen and Danny C. Price and Lister Staveley-Smith and E R Switzer and Peter T. Timbie and Laura Wolz},
  journal={Monthly Notices of the Royal Astronomical Society},
We report results from 21-cm intensity maps acquired from the Parkes radio telescope and cross-correlated with galaxy maps from the 2dF galaxy survey. The data span the redshift range 0.057 < z < 0.098 and cover approximately 1300 deg^2 over two long fields. Cross-correlation is detected at a significance of 5.7 σ. The amplitude of the cross-power spectrum is low relative to the expected dark matter power spectrum, assuming a neutral hydrogen (H i) bias and mass density equal to measurements… 

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