'Cold Quasars' May Be at the End of Their Lives, But They Can Still Birth Stars
By Nola Taylor Redd 14 June 2019
An artistic conception of an energetic quasar that has cleared out the gas and dust in the center of
the galaxy and is pushing it to the outskirts. Soon, there will be no gas and dust left to build new
stars. (Image: © Michelle Vigeant)
Building a quasar, the brightest type of object in the universe, usually signifies an end of star-formation in a galaxy. Now, new research suggests that some galaxies may continue to birth new stars longer than expected after a quasar cuts off their supply of gas.
Using observations gathered with the European Space Agency's XMM-Newton Telescope, astronomers in ongoing research revealed the additional blip in the life story of these galaxies. They suspect that the unexpectedly late star formation could be possible in all types of galaxies.
"We already knew quasars go through a dust-obscured phase … a heavily shrouded phase where dust is surrounding the supermassive black hole," lead researcher Allison Kirkpatrick, an astrophysicist at the University of Kansas, said in a statement. Kirkpatrick and her colleagues studied several intriguing quasars in the X-ray and far-infrared spectra to find quasars that hadn't lost all of their dust. "Now we've found this unique transition regime that we didn't know [about] before," she said.
Kirkpatrick is calling the new class of objects "cold quasars." She presented her results on June 12 at the 234th semiannual meeting of the American Astronomical Society in St. Louis.
More:
https://www.space.com/amp/cold-quasars-galaxies-still-forming-stars.html?utm_source=notification
