The research team, including Associate Professor Akio Inoue of Osaka Sangyo University, Assistant Professor Yoichi Tamura of the University of Tokyo, and Associate Professor Hiroshi Matsuo of the National Astronomical Observatory, will be 131 billion light years old with the world's largest radio telescope "ALMA Telescope" in Chile, South America. I found the light of ionized oxygen in another galaxy.It is the most distant discovery of oxygen in the history of observation, and proves that oxygen existed in the earliest universe.The results were published in the electronic version of the American scientific journal "Science."
Most of the elements that existed immediately after the Big Bang 138 billion years ago were hydrogen and helium, and heavy elements such as oxygen and carbon are said to have been formed during the repeated birth and disappearance of stars.Searching for the earliest heavy elements in the universe is also exploring the history of star formation at that time.It also approaches the mystery of how the galaxy, a large group of stars, was born, and what triggered the so-called "reionization of the universe."
To approach this mystery, the research group focused on the amount of oxygen, which indicates the cumulative amount of star formation and disappearance.Predict the intensity of ionized oxygen emission lines by simulating the formation and evolution of galaxies with a supercomputer.The ALMA telescope on the plateau in Chile, South America, has published a forecast paper that it can detect even from galaxies during the space reionization period in a few hours, and secured the observation time of the telescope.
Then, in June 2015, we succeeded in detecting ionized oxygen light in observations targeting the galaxy "SXDF-NB6-131" located 1006 billion light-years away.It is a distance that goes back 2 million years from the oldest 122 billion years, and it is a result that proves that oxygen existed in the earliest universe 9 million years before the birth of the universe.
The team is observing oxygen in the galaxy 133 billion light-years away, and plans to advance the understanding of the galaxy's gas motion by observing the Doppler effect of oxygen light with high resolution.It is hoped that important clues will be obtained in the future to clarify what kind of galaxy caused the "reionization of the universe".
