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Updated: Nov 17, 2025

The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry
Published on: August 12, 2013
A massive stellar bulge in a regularly rotating galaxy 1.2 billion years after the Big Bang
Federico Lelli1,2, Enrico M Di Teodoro3, Filippo Fraternali4
1School of Physics and Astronomy, Cardiff University, Cardiff CF24 3AA, UK. federico.lelli@inaf.it.
Abstract:
Cosmological models predict that galaxies forming in the early Universe experience a chaotic phase of gas accretion and star formation, followed by gas ejection due to feedback processes. Galaxy bulges may assemble later via mergers or internal evolution. Here we present submillimeter observations (with spatial resolution of 700 parsecs) of ALESS 073.1, a starburst galaxy at redshift [Formula: see text] when the Universe was 1.2 billion years old. This galaxy's cold gas forms a regularly rotating disk with negligible noncircular motions. The galaxy rotation curve requires the presence of a central bulge in addition to a star-forming disk. We conclude that massive bulges and regularly rotating disks can form more rapidly in the early Universe than predicted by models of galaxy formation.
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