ESA | Science & Technology | Herschel | 2017 Dec 07
[img3="Artist's impression of radio-loud quasar in star-forming galaxy.Astronomers have used ESA's Herschel Space Observatory to solve a decades-old mystery about the origin of powerful cool gas winds in the hot environs of quasars. The evidence linking these powerful winds to star formation in the quasar host galaxies may also help resolve the mystery of why the size of galaxies in the Universe appears to be capped. ...
Credit: ESA/C. Carreau"]http://sci.esa.int/science-e-media/img/ ... r_625w.jpg[/img3][hr][/hr]
For five decades, astronomers have studied the spectra of quasars to uncover the origin of the electromagnetic radiation they emit and to trace the path the light has traversed to reach us. ...
Astronomers have observed absorption lines in many quasars that are indicative of absorption en route by cool gas with heavy metal elements like carbon, magnesium and silicon. The lines signal that the light has travelled through winds of cold gas travelling at speeds of thousands of kilometres per second within the quasars' host galaxies. Whilst knowledge that these winds exist is nothing new their origin, and why they are able to reach such impressive speeds, has remained an unknown. ...
Using data obtained with ESA's Herschel Space Observatory the astronomers have shown, for the first time, that the strength of the metal absorption lines associated with these mysterious gas winds is directly linked to the rate of star formation within the quasar host galaxies. In finding this trend the astronomers are able to say with some confidence that prodigious star formation within the host galaxy may be the mechanism driving these mysterious and powerful winds. ...
Starburst-Driven Superwinds in Quasar Host Galaxies - Peter Barthel et al
- Astrophysical Journal Letters 843(1):L16 (2017 Jul 01) DOI: 10.3847/2041-8213/aa7631
arXiv.org > astro-ph > arXiv:1706.00194 > 2017 Jun 01