Measuring the Distance Between Quasar Pairs Just Got Easier
A new way to accurately measure the distance between quasar pairs is showing promise through University of Alberta research.
Astronomers use distance and recessional velocity to measure the expansion of the universe. This is typically done with individual galaxies, but measuring quasar pairs proved challenging. These quasars, powered by supermassive black holes in colliding galaxies, often have gas pushed outward so rapidly that their measured velocity deviates significantly from the actual velocity.
This caused errors of up to 10 million light-years when measuring line-of-sight separation. The University of Alberta's researchers have now developed a more accurate method for measuring the distance between double quasars. This Quasar Proximity Effect (QPE) approach examines hydrogen absorption lines in the regions of gas around a quasar that is illuminated and heated by its light.
By using simulations and algorithms, the scientists applied this method to measure distances between quasar pairs. The results showed that this new method provides more precise distance estimates than traditional redshift measurements. While previous methods had errors of tens of millions of light-years, the new method can determine the physical separation of a quasar pair to within just half a million light-years.
This method can be applied to existing quasar-pair data, avoiding the need for new observations that could take years to obtain. The researchers believe this approach has significant potential and plan to further refine the method's precision.
Written by urgent.news from Universe Today's reporting — not their text. Machine-written — may contain errors; check the original before relying on it.
