Extracting the Global Cosmological 21-cm Signal From EDGES Data Using MCMC

摘要

The 21-cm spectral line emitted by neutral hydrogen in the intergalactic medium (IGM) at redshifts > 6, can be used to characterize the first generations of stars, galaxies, and black holes in the Universe. Due to redshift, the 21-cm signal is expected at frequencies < 200 MHz for z > 6. The Experiment to Detect the Global EoR Signature (EDGES) measures the sky-average, or global, brightness temperature spectrum in the frequency range 50–200 MHz, with the objective of characterizing the cosmological 21-cm signal. The EDGES instruments are single-antenna, absolutely-calibrated, total-power radiometers. They conduct observations from the Murchison Radio-astronomy Observatory in Western Australia.