ALMA Detects the Majority Distant Signs of Oxygen in the Space - Physics-Astronomy.org

ALMA Detects the Majority Distant Signs of Oxygen in the Space

Astronomers from Japan, Sweden, the United Kingdom and ESO have used the Atacama Large Millimetre/submillimetre Array (ALMA) to view one of the most distant galaxies known. SXDF-NB1006-2 lies at a redshift of 7.2, sense that we see it only 700 million years after the Big Bang.
The group was hoping to find out about the heavy chemical rudiments present in the galaxy, as they can tell us about the level of star shape, and hence provide clues about the period in the record of the space known as cosmic reionisation.
“Seeking heavy elements in the early on universe is an essential approach to discover the star formation activity in that time,” said Akio Inoue of Osaka Sangyo University, Japan, the guide author of the research paper, which is person published in the journal Science. “Studying heavy elements as well gives us a hint to appreciate how the galaxies were formed and what cause the cosmic reionisation,” he added.
In the time before matter formed in the universe, it was full with electrically neutral gas. But when the first objects began to shine, a little hundred million years after the Big Bang, they emitted great radiation that in progress to break up those neutral atoms — to ionise the gas. During this phase — known as cosmic reionisation — the whole space changed dramatically. But there is much debate about exactly what kind of substance caused the reionisation. Studying the conditions in very far-away galaxies can help to reply this question.
Before observing the far-away galaxy, the researchers perform computer simulations to predict how easily they could expect to see proof of ionised oxygen with ALMA. They also careful observations of similar galaxies that are much closer to Earth, and finished that the oxygen emission should be detectable, even at vast distance.
They then approved out high-sensitivity observations with ALMA and establish light from ionised oxygen in SXDF-NB1006-2, making this the majority distant unambiguous detection of oxygen ever obtain. It is firm evidence for the attendance of oxygen in the early universe, only 700 million years following the Big Bang.Oxygen in SXDF-NB1006-2 was establish to be 10 times less abundant than it is in the Sun. “The small abundance is predictable because the universe was still young and had a short record of star shape at that point in time,” commented Naoki Yoshida at the University of Tokyo. “Our simulation in fact predicted an profusion ten times smaller than the Sun. But we have another, unforeseen, result: a very small amount of dust.”
The team was unable to notice any emission from carbon in the galaxy, suggesting that this young galaxy contains extremely little un-ionised hydrogen gas, and also establish that it contains only a small amount of dust, which is complete up of heavy elements. “Something strange may be happening in this galaxy,” said Inoue. “I suspect that almost every the gas is highly ionised.”The detection of ionised oxygen indicates that a lot of very brilliant stars, several dozen times more massive than the Sun, have formed in the galaxy and are emitting the strong ultraviolet light needed to ionise the oxygen atoms.
The lack of dirt in the galaxy allows the intense ultraviolet glow to escape and ionise vast amounts of gas outside the galaxy. “SXDF-NB1006-2 would be a prototype of the light sources accountable for the cosmic reionisation,” said Inoue.
“This is an important step towards understanding what type of objects caused cosmic reionisation,” explained Yoichi Tamura of the University of Tokyo. “Our next observations with ALMA have already started. Higher decree observations will allow us to see the distribution and movement of ionised oxygen in the galaxy and give vital information to help us appreciate the property of the galaxy.”
ALMA Detects the Majority Distant Signs of Oxygen in the Space

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