Chromatic effects in the 21 cm global signal from the cosmic dawn

@article{Vedantham2014ChromaticEI,
  title={Chromatic effects in the 21 cm global signal from the cosmic dawn},
  author={Harish K. Vedantham and L{\'e}on V. E. Koopmans and A. G. de Bruyn and Stefan J. Wijnholds and Benedetta Ciardi and Michiel Brentjens},
  journal={Monthly Notices of the Royal Astronomical Society},
  year={2014},
  volume={437},
  pages={1056-1069}
}
The redshifted 21 cm brightness distribution from neutral hydrogen is a promising probe into the cosmic dark ages, cosmic dawn and re-ionization. Low Frequency Array's (LOFAR) Low Band Antennas (LBA) may be used in the frequency range 45 to 85 MHz (30 > z > 16) to measure the sky-averaged redshifted 21 cm brightness temperature as a function of frequency, or equivalently, cosmic redshift. These low frequencies are affected by strong Galactic foreground emission that is observed through… 
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