protogalaxy

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pro·to·gal·ax·y

 (prō′tō-găl′ək-sē)
n. pl. pro·to·gal·ax·ies
A cloud of gas, primarily hydrogen, that is forming a galaxy or has sufficient mass to eventually form a galaxy.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

protogalaxy

(ˌprəʊtəʊˈɡæləksɪ)
n, pl -axies
(Astronomy) a cloud of gas in the early stages of its evolution into a galaxy
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
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In (http://www.nature.com/articles/s41550-017-0075) the paper , titled "Rapid formation of massive black holes in close proximity to embryonic protogalaxies," he argues that the ancient supermassive black holes could not have formed through the conventional method of accretion of gas.
Small protogalaxies of dark matter and gas appeared first, then merged with each other to form galaxies, galaxy groups and, eventually, galaxy clusters.
Our galaxy, though, "is not big and crazy; it's more typical." To find those more classic, less showy protogalaxies requires a really big magnifying glass.
Shchekinov, "First supernovae in dwarf protogalaxies," Astronomy & Astrophysics, vol.
Black holes need cool gas to grow so this would have slowed down the growth of other black holes in smaller protogalaxies, even as the growth of black holes in the most massive protogalaxies continued quickly.
Some areas explored include formation and evolution of primordial black holes, turbulent formation of protogalaxies at the end of the plasma epoch, and tracking order and chaos in a binary quasar dynamical model.
if larger, no star condensation within the protogalaxies;
`Dark gas clouds are interesting because they could be protogalaxies, (clouds of gas that haven't managed to form stars), or they could be debris from the formation of other galaxies,' Staveley-Smith says.
They will see the missing links between the protogalaxies of long ago and the stars and galaxies we study today.
In some recent simulations of growing protogalaxies, the black hole seemed to be "breathing," its accretion rate rising and falling as feedback from nearby exploding stars turned on and off, Volonteri says.
This gas, most of which is present in the space between the protogalaxies, would then have been released when these stars went supernova.
Just a minuscule fraction of a second of inflation would have spread matter out uniformly except for tiny clumps--fluctuations in the background density--to serve as seeds around which the first protogalaxies could grow.