ALMA | ESO | NRAO | NAOJ | 2018 Jun 04
Astronomers using ALMA and the VLT have discovered that both starburst galaxies in the early Universe and a star-forming region in a nearby galaxy contain a much higher proportion of massive stars than is found in more peaceful galaxies. These findings challenge current ideas about how galaxies evolved, changing our understanding of cosmic star-formation history and the build up of chemical elements.Artist’s impression of distant starburst galaxy - Credit: ESO/M. Kornmesser
Probing the distant Universe a team of scientists, led by University of Edinburgh astronomer Zhi-Yu Zhang, used the Atacama Large Millimeter/submillimeter Array (ALMA) to investigate the proportion of massive stars in four distant gas-rich starburst galaxies . These galaxies are seen when the Universe was much younger than it is now so the infant galaxies are unlikely to have undergone many previous episodes of star formation, which might otherwise have confused the results.
Zhang and his team developed a new technique — analogous to radiocarbon dating (also known as carbon-14 dating) — to measure the abundances of different types of carbon monoxide in four very distant, dust-shrouded starburst galaxies . They observed the ratio of two types of carbon monoxide containing different isotopes . ...
Stellar populations dominated by massive stars in dusty starburst galaxies across cosmic time - Zhi-Yu Zhang et al