An international team led by researchers from the University of Minnesota in Minneapolis and St. Paul and Ohio State University has achieved a breakthrough in precision cosmology: they measured the amount of helium formed in the first five minutes after the Big Bang with an uncertainty of just 0.5%, three times more precise than all previous estimates, infohub.kz reports.
The results appear in five papers in The Astrophysical Journal. The observations were carried out using the Large Binocular Telescope.
To reach the stated precision, the team conducted 130 hours of observations, studying 15 small, distant galaxies with primordial chemical composition. These objects have undergone virtually no chemical evolution over 13.8 billion years and served as cosmic "time capsules."
Using MODS spectrographs built at Ohio State University, the scientists analyzed more than 10 helium spectral lines and 15 hydrogen lines simultaneously, which allowed them to eliminate minor sources of error.
According to University of Minnesota professor Evan Skillman, precise data on primordial helium provide a powerful tool for testing the Standard Model of physics and calculating the number of neutrino families in the early universe.
Professor Richard Pogge of Ohio State University added that developing the spectrographs took 12 years, and they successfully met a task of fundamental importance.