TY - JOUR
T1 - Astrophysical constraints from the SARAS 3 non-detection of the cosmic dawn sky-averaged 21-cm signal
AU - Bevins, H. T.J.
AU - Fialkov, A.
AU - de Lera Acedo, E.
AU - Handley, W. J.
AU - Singh, S.
AU - Subrahmanyan, R.
AU - Barkana, R.
N1 - Publisher Copyright:
© 2022, The Author(s), under exclusive licence to Springer Nature Limited.
PY - 2022/12
Y1 - 2022/12
N2 - Observations of the redshifted 21-cm line of atomic hydrogen have provided several upper limits on the 21-cm power spectrum and a tentative detection of the sky-averaged signal at redshift z ≈ 17. Made with the Experiment to Detect the Global EoR Signature (EDGES) low-band antenna, this claim was recently disputed by the SARAS 3 experiment, which reported a non-detection and is the only available upper limit strong enough to constrain cosmic dawn astrophysics. We use these data to constrain a population of radio-luminous galaxies ~200 million years after the Big Bang (z ≈ 20). We find, using Bayesian data analysis, that the data disfavour (at 68% confidence) radio-luminous galaxies in dark-matter haloes with masses of 4.4 × 105 M⊙ ≲ M ≲ 1.1 × 107 M⊙ (where M⊙ is the mass of the Sun) at z = 20 and galaxies in which >5% of the gas is converted into stars. The data disfavour galaxies with a radio luminosity per star formation rate of Lr/SFR ≳ 1.549 × 1025 W Hz−1 M⊙−1 yr at 150 MHz, around 1,000 times brighter than today, and, separately, a synchrotron radio background in excess of the cosmic microwave background by ≳6% at 1.42 GHz.
AB - Observations of the redshifted 21-cm line of atomic hydrogen have provided several upper limits on the 21-cm power spectrum and a tentative detection of the sky-averaged signal at redshift z ≈ 17. Made with the Experiment to Detect the Global EoR Signature (EDGES) low-band antenna, this claim was recently disputed by the SARAS 3 experiment, which reported a non-detection and is the only available upper limit strong enough to constrain cosmic dawn astrophysics. We use these data to constrain a population of radio-luminous galaxies ~200 million years after the Big Bang (z ≈ 20). We find, using Bayesian data analysis, that the data disfavour (at 68% confidence) radio-luminous galaxies in dark-matter haloes with masses of 4.4 × 105 M⊙ ≲ M ≲ 1.1 × 107 M⊙ (where M⊙ is the mass of the Sun) at z = 20 and galaxies in which >5% of the gas is converted into stars. The data disfavour galaxies with a radio luminosity per star formation rate of Lr/SFR ≳ 1.549 × 1025 W Hz−1 M⊙−1 yr at 150 MHz, around 1,000 times brighter than today, and, separately, a synchrotron radio background in excess of the cosmic microwave background by ≳6% at 1.42 GHz.
UR - http://www.scopus.com/inward/record.url?scp=85142880965&partnerID=8YFLogxK
U2 - 10.1038/s41550-022-01825-6
DO - 10.1038/s41550-022-01825-6
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AN - SCOPUS:85142880965
SN - 2397-3366
VL - 6
SP - 1473
EP - 1483
JO - Nature Astronomy
JF - Nature Astronomy
IS - 12
ER -