Astronomers Realize Dark Matter Has Been Magnifying Cosmic Readings
The surface facility for IceCube, with the rest being below the ice.
Credit: IceCube Neutrino Observatory
Researchers from the Max Planck Institute for Radio Astronomy have announced new research suggesting that neutrino detections at the Arctic IceCube Neutrino Observatory could be explained by dark matter lensing of readings from blazars.
So, what does that actually mean?
In astronomy, three elements are always at play: the actual event, the path information from that event takes as it travels to Earth, and the scientific reading astronomers collect.
Two of these are always needed to know the third for certain, but often astronomers have no choice but to assume a clean, unperturbed path for the readings they collect. Without such an assumption, which is wrong sometimes but right most of the time, they wouldn’t be able to interpret their own observations.
Still, astronomers try to avoid assumptions whenever possible, charting a particle’s path and accounting for anything that could affect its properties as it travels. When they’re able to do this correctly, it allows correction of the post-trip observations to better reflect the reality of the actual event.
Enter object PKS 2233-148, a so-called blazar. A quasar is a particular type of “active galactic nucleus,” or a supermassive black hole with matter around it but no larger galaxy around that. As the supermassive black hole at the center of a quasar sucks up matter, the quasar emits jets of extremely powerful radiation in two opposite directions.
Credit: IceCube Collaboration/NSF
A blazar is a subtype of quasar oriented so one of these jets points directly at Earth. By observing PKS 2233-148 with the Very Long Baseline Array (VLBA), the Fermi space telescope, and the Swift space observatory, researchers were able to watch its behavior in visible light, X-rays, and gamma rays simultaneously.
They found that the jet does not always appear where it should, indicating disturbances in the jet’s path. Without any visible matter to cause this deflection, the team posits that they’ve discovered the first emissions gravitationally deflected by a filament of dark matter.
This gravitational lensing can be useful in several ways, in particular through the expansion of clustered rays, which amounts to magnification. Not only could the timing of the lensing versus neutrino detection help reveal the blazar’s black hole core as a neutrino factory, but it could also help astronomers look deeper into that core to reveal the mechanisms at work.
Neutrinos are an area of active research, with astronomers attempting to figure out how to detect, analyze, and track one of the most elusive particles in the cosmos. We’ll keep you updated as it rapidly progresses.
