Star-formation ‘Fuel Tanks’ Found around Distant Galaxies from the Early Universe

The observed CH+ reveals dense shock waves, powered by hot, fast galactic winds originating inside the galaxies’ star-forming regions. These winds flow through a galaxy and push material out of it. Their turbulent motions are such that the galaxy’s gravitational pull can recapture part of that material. This material then gathers into turbulent reservoirs of cool, low-density gas, extending more than 30,000 light-years from the galaxy’s star-forming region.

“With CH+, we learn that energy is stored within vast galaxy-sized winds and ends up as turbulent motions in previously unseen reservoirs of cold gas surrounding the galaxy,” said Falgarone. “Our results challenge the theory of galaxy evolution. By driving turbulence in the reservoirs, these galactic winds extend the starburst phase instead of quenching it.”

The team determined that galactic winds alone could not replenish the newly revealed gaseous reservoirs. The researchers suggest that the mass is provided by galactic mergers or accretion from hidden streams of gas, as predicted by current theory.

“This discovery represents a major step forward in our understanding of how the inflow of material is regulated around the most intense starburst galaxies in the early universe,” says ESO’s Director for Science, Rob Ivison, a co-author on the paper. “It shows what can be achieved when scientists from a variety of disciplines come together to exploit the capabilities of one of the world’s most powerful telescopes.”

The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.

Contacts and sources:
Charles BlueNational Radio Astronomy Observatory

Citation: “Large turbulent reservoirs of cold molecular gas around high redshift starburst galaxies” by E. Falgarone et al., appearing in Nature [http://www.nature.com/nature/journal/v548/n7668/full/nature23298.html]