HERA Phase I Limits on the Cosmic 21 cm Signal: Constraints on Astrophysics and Cosmology during the Epoch of Reionization

  title={HERA Phase I Limits on the Cosmic 21 cm Signal: Constraints on Astrophysics and Cosmology during the Epoch of Reionization},
  author={The Hera Collaboration Zara Abdurashidova and James E. Aguirre and Paul Alexander and Zaki S. Ali and Yanga Balfour and Rennan Barkana and Adam P. Beardsley and Gianni Bernardi and Tashalee S. Billings and Judd D. Bowman and Richard F. Bradley and Phillip Bull and Jacob Burba and Steve H. Carey and Christopher L. Carilli and Carina Cheng and David R. DeBoer and Matt Dexter and Eloy de Lera Acedo and Joshua S. Dillon and J. A. Ely and Aaron Ewall-Wice and Nicolas Fagnoni and Anastasia Fialkov and Randall Fritz and Steven R. Furlanetto and Kingsley Gale-Sides and B. E. Glendenning and Deepthi Gorthi and Bradley Greig and Jasper Grobbelaar and Ziyaad Halday and Bryna J. Hazelton and Stefan Heimersheim and Jacqueline N. Hewitt and Jack Hickish and Daniel C. Jacobs and Austin Julius and Nicholas S. Kern and Joshua Kerrigan and Piyanat Kittiwisit and Saul A. Kohn and Matthew Kolopanis and Adam E. Lanman and Paul La Plante and Telalo Lekalake and David Lewis and Adrian Liu and Yin-Zhe Ma and David Macmahon and Lourence Malan and Cresshim Malgas and M. D. J. Maree and Zachary E. Martinot and Eunice Matsetela and Andrei Mesinger and Jordan Mirocha and Mathakane Molewa and Miguel F. Morales and Tshegofalang Mosiane and Julian B. Mu{\~n}oz and S. Murray and Abraham R. Neben and Bojan Nikoli{\'c} and Chuneeta D. Nunhokee and Aaron Parsons and Nipanjana Patra and Samantha Pieterse and Jonathan C. Pober and Yuxiang Qin and Nima Razavi-Ghods and Itamar Reis and Jon Ringuette and James Robnett and Kathryn Rosie and Mario G Santos and Sudipta Sikder and Peter H Sims and Craig H. Smith and Angelo Syce and Nithyanandan Thyagarajan and Peter K. G. Williams and Haoxuan Zheng},
  journal={The Astrophysical Journal},
Recently, the Hydrogen Epoch of Reionization Array (HERA) has produced the experiment’s first upper limits on the power spectrum of 21 cm fluctuations at z ∼ 8 and 10. Here, we use several independent theoretical models to infer constraints on the intergalactic medium (IGM) and galaxies during the epoch of reionization from these limits. We find that the IGM must have been heated above the adiabatic-cooling threshold by z ∼ 8, independent of uncertainties about IGM ionization and the radio… 
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