Apr 15 2020
With the help of the Gemini North telescope installed on Hawaii’s Maunakea, scientists have identified the most energetic outflow from any quasar measured so far.
The image at left shows an artist’s conception of the central portion of the galaxy that hosts the quasar SDSS J135246.37+423923.5 viewed at optical wavelengths. Thick winds obscure our view, and imprint signatures of the energetic outflow on the SDSS spectrum. The image at right shows the same artist’s view at infrared wavelengths, as seen by the Gemini GNIRS detector. The thick outflow is transparent at infrared wavelengths, giving us a clear line of sight to the quasar. The infrared spectrum yields the quasar redshift, and from that reference frame, we measured the record-breaking outflow velocity. Image Credit: International Gemini Observatory/NOIRLab/NSF/AURA/P. Marenfeld.
Moving at almost 13% of the speed of light, this energetic wind carries a sufficient amount of energy to considerably influence the formation of stars across a whole galaxy. For 15 years, the extragalactic tempest had remained invisible from plain sight before it was uncovered by novel computer modeling and the latest data obtained from the international Gemini Observatory.
Now, utilizing observations from the international Gemini Observatory—a program of NSF’s NOIRLab—a group of astronomers has now revealed the most energetic outflow from a distant quasar.
This intense energetic outflow is now traveling into its host galaxy at nearly 13% of the speed of light, and it emerges from a quasar called SDSS J135246.37+423923.5 which is located approximately 10 billion light-years from the Earth.
While high-velocity winds have previously been observed in quasars, these have been thin and wispy, carrying only a relatively small amount of mass. The outflow from this quasar, in comparison, sweeps along a tremendous amount of mass at incredible speeds. This wind is crazy powerful, and we don’t know how the quasar can launch something so substantial.
Sarah Gallagher, Astronomer, Associate Professor, Physics and Astronomy, Western University
Gallagher had also headed the Gemini observations.
Apart from quantifying the energetic outflow from the quasar SDSS J135246.37+423923.5, the researchers were able to deduce the mass of the giant black hole that powers this quasar. This giant object is 8.6 billion times bigger than that of the Sun—roughly 50% more massive than Messier 87—the famous black hole in the galaxy—and 2000 times more than the mass of the black hole present in the middle of the Milky Way.
The result of the study has been published in The Astrophysical Journal and the quasar analyzed in this work currently holds the record for the most energetic wind from a quasar, ever measured. This includes an outflow that is more energetic when compared to those newly reported, in analyses of 13 quasars.
In spite of its energetic outflow and mass, the discovery of this extragalactic tempest remained hidden in a quasar survey for a period of 15 years. And now, the combination of the researchers’ novel computer modeling technique and the Gemini data enabled this powerhouse to be analyzed thoroughly.
We were shocked—this isn’t a new quasar, but no one knew how amazing it was until the team got the Gemini spectra. These objects were too hard to study before our team developed our methodology and had the data we needed, and now it looks like they might be the most interesting kind of windy quasars to study.
Karen Leighly, Study Lead and Astronomer, University of Oklahoma
Quasars—also called quasi-stellar objects—can be described as a kind of unusual luminous astrophysical object that dwells in the cores of large galaxies. The quasars contain a giant black hole enclosed by a luminous disk of gas, and they can outperform all the stars in their host galaxy and drive winds that are strong enough to impact the whole galaxies.
Some quasar-driven winds have enough energy to sweep the material from a galaxy that is needed to form stars and thus quench star formation. We studied a particularly windy quasar, SDSS J135246.37+423923.5, whose outflow is so thick that it’s difficult to detect the signature of the quasar itself at visible wavelengths.
Hyunseop (Joseph) Choi, Study First Author and Graduate Student, University of Oklahoma
Regardless of the obstruction, the researchers were able to clearly observe the quasar with the help of the Gemini Near-Infrared Spectrograph (GNIRS) installed on Gemini North to view at infrared wavelengths.
Then, using a combination of a revolutionary computer modeling and high-quality spectra from the International Gemini Observatory, the astronomers revealed the nature of the energetic outflow from the object—which exceptionally demonstrated to be more energetic than that of any quasar outflow measured in the past.
The researchers’ finding raises some crucial questions, and also indicates that more of these quasars could perhaps be waiting to be discovered.
“We don’t know how many more of these extraordinary objects are in our quasar catalogs that we just don’t know about yet,” added Choi “Since automated software generally identifies quasars by strong emission lines or blue color—two properties our object lacks—there could be more of these quasars with tremendously powerful outflows hidden away in our surveys.”
“This extraordinary discovery was made possible with the resources provided by the international Gemini Observatory; the discovery opens new windows and opportunities to explore the Universe further in the years to come,” stated Martin Still, an astronomy program director at the National Science Foundation, which financially supports the Gemini Observatory from the United States as part of an international association.
“The Gemini Observatory continues to advance our knowledge of the Universe by providing the international science community with forefront access to telescope instrumentation and facilities,” concluded Martin Still.
Source: https://nationalastronomy.org/