For something that doesn’t emit light We can find outAnd black holes They like to cover themselves with brightness.
Some of the brightest light in the universe actually comes from supermassive black holes. Well, not really black holes; It is the matter that surrounds them, as it actively reduces a wide variety of materials from its immediate environment.
These bright swirls of hot, spinning material contain galaxies called blazars. Not only do they glow with the heat of the rotating line, they also radiate matter as magnifications of “flame” rays through space.
Scientists have finally discovered the mechanism that generates the very high-energy light that reaches us billions of years ago: shocks Black holeJets that accelerate particles to dizzying speeds.
“It’s a 40-year-old mystery and we’ve been able to solve it.” says astronomer Yannis Lioudakis Finnish Center for Astronomy with ESO (FINCA). “Finally we got all the puzzle pieces in and the picture they painted was clear.”
Most of the galaxies in the universe are built around a supermassive black hole. These incredibly large objects are found in the center of galaxies and sometimes do very little (eg arc a*The black hole in the heart of the Milky Way) and sometimes it’s too much.
This activity consists in the collection of materials. A large cloud in the equatorial disk gathers around the black hole and orbits it. water around the drain. Frictional and gravitational interactions in the outer space around the black hole cause this matter to heat up and glow brightly in a range of wavelengths. This is one of the light sources of a black hole.
Another — blazar-sounding — are twin jets of material shot perpendicular to the disk from the polar regions outside the black hole. Rather than falling towards the black hole, these jets are thought to be material from the inner edge of the disk, which is accelerated to the poles via external magnetic field lines and fired off at very high speeds approaching the speed of light. .
To classify a galaxy as a blazar, these jets must point directly at the observer. We are the only ones on Earth. Due to the intense acceleration of the particles, they shine with light across the electromagnetic spectrum, including gamma rays and high-energy X-rays.
How this jet accelerates particles to such high speeds has been a huge cosmological problem for decades. But now there is a powerful new X-ray telescope called Polarimetry Explorer (X-ray Imaging Explorer).IXPE extension), launched in December 2021, scientists hold the key to solving the mystery. It was the first space telescope to detect the direction or polarization of X-rays.
‘Early measurements of the X-ray polarization of this type of source allowed for the first time direct comparisons with models developed from observations of other frequencies of light, from radio to very high-energy gamma rays.’ says astronomer Imagolatha Donnarumma Italian Space Agency.
became IXPE High-energy luminous material In our sky, a blazar named Markarian 501 resides 460 million light-years away in the constellation Hercules. For six days in March 2022, the telescope collected data on the X-ray light emitted by the Blazar aircraft.
At the same time, other observers were measuring light from other wavelength ranges, from radio to optical data, data previously available only for Markarian 501.
The team soon noticed a strange difference in the X-ray light. Their direction is significantly more distorted or polarized than at lower energy wavelengths. Optical light is more polarized than radio waves.
However, the direction of polarization was similar for all wavelengths and compatible with the direction of flux. The team found that this is consistent with models where bumps in aircraft generate shock waves that provide additional acceleration along the plane. Closer to the shock, this acceleration is at its maximum, producing X-rays. Along the plane, the particles lose energy, producing lower-energy, less polarized light and radio emissions.
“As the shock wave passes through the region, the magnetic field strengthens and the energy of the particles increases.” says astronomer Alan Marcher Boston University. “The energy comes from the kinetic energy of the object creating the shock wave.”
It’s not clear why the collisions occur, but one possible mechanism is that the faster-moving material in the plane reaches the slower-moving agglomerates, creating collisions. Future research will help confirm this hypothesis.
Because blazars are among the most powerful particle accelerators in the universe and one of the best laboratories for understanding extreme physics, this research is an important piece of the puzzle.
Future research will continue to monitor Markarian 501 and transfer IXPE to other blazars to see if similar polarizations can be detected.
Published in the thesis natural astronomy.
