The Canadian Hydrogen Intensity Mapping Experiment (CHIME) telescope has achieved its first standalone detection of hydrogen glow from when the universe was approximately five billion years old, representing a significant breakthrough in cosmological research. This international collaboration included researchers from India's Raman Research Institute, an autonomous institute of the Department of Science and Technology, and was published in The Astrophysical Journal with DOI 10.3847/1538-4357/ae9835.
The detection method uses the telescope's own data to map the faint radio emission of hydrogen gas, which acts as a cosmic tracer revealing matter distribution across space. This technique provides a new window for studying cosmic expansion and investigating dark energy, the mysterious force driving the universe's accelerating expansion. The finding demonstrates that CHIME can conduct these investigations independently without requiring cross-correlation with galaxy survey data from other telescopes, making the research faster and less expensive than previous methods.
The data analysis revealed that approximately two percent of the hydrogen in the universe was in neutral atomic form during this period, consistent with other measurements. Researchers used 94 nights of observation data collected in 2019 and applied new data analysis techniques to isolate the faint signal from background noise. The team spent over a year verifying the finding before publication. With nearly seven years of observations now available, researchers are expanding the analysis to include earlier cosmic periods when the universe was only three billion years old.