Tight constraints on the excess radio background at z = 9.1 from LOFAR

  title={Tight constraints on the excess radio background at z = 9.1 from LOFAR},
  author={Rajesh Mondal and Anastasia Fialkov and C. Fling and Ilian T Iliev and Rennan Barkana and Benedetta Ciardi and Garrelt Mellema and Saleem Zaroubi and L{\'e}on V. E. Koopmans and F G Mertens and B K Gehlot and Raghunath Ghara and A. Ghosh and Sambit K. Giri and Andr{\'e} R. Offringa and Vishambhar N. Pandey},
  journal={Monthly Notices of the Royal Astronomical Society},
The ARCADE2 and LWA1 experiments have claimed an excess over the Cosmic Microwave Background (CMB) at low radio frequencies. If the cosmological high-redshift contribution to this radio background is between 0.1% and 22% of the CMB at 1.42 GHz, it could explain the tentative EDGES Low-Band detection of the anomalously deep absorption in the 21-cm signal of neutral hydrogen. We use the upper limit on the 21-cm signal from the Epoch of Reionization ($z=9.1$) based on 141 hours of observations… Expand

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