Amazing stuff! New telescopes, new insights!
When will humans have answers for the fundamental question of what came before the Big Bang?
It appears, I found the preprint of this research article: Extreme damped Lyman-α absorption in young star-forming galaxies at z=9−11 (unfortunately, the authors did not update the preprint to match the journal article)
"For the first time in the history of astronomy, researchers at the Niels Bohr Institute have witnessed the birth of three of the universe's absolute earliest galaxies, somewhere between 13.3 and 13.4 billion years ago. ..."
From the Perspective abstract:
"Hydrogen in the intergalactic medium, the diffuse gas that permeates the space between galaxies, exists today in an ionized state. Yet, this hasn’t always been the case. Very early on, approximately 400,000 years after the Big Bang, the intergalactic medium was primarily neutral. The subsequent transition to an ionized universe, known as reionization, lasted about a billion years and remains poorly understood. Ionization occurs when hydrogen absorbs a photon from the far-ultraviolet (UV) region of the electromagnetic spectrum, which breaks the electron-nucleus bond. It is thought that the first stars and galaxies initiated this transformation. ... however ... Heintz et al. report three galaxies harboring substantial reservoirs of neutral hydrogen a few hundreds of millions of years after the Big Bang, a time when this transition is expected to occur. This challenges the role that early galaxies play in the reionization process."
From the editor's note and abstract:
"Editor’s summary
Gas in galaxies provides the raw material for star formation. Galaxies in the early Universe are seen to be forming stars rapidly ..., but the amount of gas they contain is difficult to determine observationally. Heintz et al. analyzed near-infrared spectroscopy of 12 galaxies at redshifts greater than eight, equivalent to less than 600 million years after the Big Bang. They identified three galaxies with characteristic rest-frame ultraviolet absorption caused by neutral hydrogen gas located in and around the galaxy. The high column densities of gas are sufficient to sustain the rapid star formation occurring in those galaxies, but only for a short period. ...
Abstract
Primordial neutral atomic gas, mostly composed of hydrogen, is the raw material for star formation in galaxies. However, there are few direct constraints on the amount of neutral atomic hydrogen (H i) in galaxies at early cosmic times. We analyzed James Webb Space Telescope (JWST) near-infrared spectroscopy of distant galaxies, at redshifts ≳8. From a sample of 12 galaxies, we identified three that show strong damped Lyman-α absorption due to H i in their local surroundings. The galaxies are located at spectroscopic redshifts of 8.8, 10.2, and 11.4, corresponding to 400 to 600 million years after the Big Bang. They have H i column densities ≳1022 cm−2, which is an order of magnitude higher than expected for a fully neutral intergalactic medium, and constitute a gas-rich population of young star-forming galaxies."
Birth of universe’s earliest galaxies observed for first time (original press release) THE UNIVERSE Using the James Webb Space Telescope, University of Copenhagen researchers have become the first to see the formation of three of the earliest galaxies in the universe, more than 13 billion years ago. The sensational discovery contributes important knowledge about the universe and is now published in the prestigious journal Science.
A struggle to reionize the Universe? (Perspective, no public access) Reservoirs of neutral hydrogen may block ionizing radiation from escaping distant galaxies
Strong damped Lyman-α absorption in young star-forming galaxies at redshifts 9 to 11 (no public access)
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