A team of researchers, including UCLA, has observed a gamma-ray flare from the galaxy M87’s supermassive black hole, providing crucial insights into particle acceleration near black holes. The flare, seven orders of magnitude larger than the event horizon, offers a rare opportunity to study high-energy particles accelerated by intense magnetic fields.
The first-ever photo of a black hole was published in 2019, capturing an image of M87’s supermassive black hole at its center. This black hole has surprised scientists again with a teraelectronvolt gamma-ray flare, emitting photons billions of times more energetic than visible light. Such flares have not been observed in over a decade.
The jet coming out of the center of M87 is seven orders of magnitude larger than the event horizon, and the bright burst of high-energy emission was well above typical radio telescope energies. The flare lasted about three days and emerged from a region less than three light-days in size, approximately 15 billion miles away.
Gamma rays have the most energy of any wavelength in the electromagnetic spectrum, produced by the hottest environments in the universe, such as regions around black holes. Photons with several teraelectronvolts of energy are vastly more energetic than visible light photons.
As matter falls toward a black hole, it forms an accretion disk where particles are accelerated due to gravitational potential energy loss. Powerful magnetic fields redirect particles away from the black hole’s poles, creating jets driven by intense magnetic fields. This process is irregular, causing rapid energy outbursts called flares.
The researchers used VERITAS and other observational facilities to detect the flare, analyzing high-energy gamma rays collected during the study. The dataset provided a comprehensive view of spectral energy distribution across different wavelengths of light.
“We still don’t fully understand how particles are accelerated near black holes or within jets,” said Weidong Jin, postdoctoral researcher at UCLA. “Our study presents the most comprehensive spectral data ever collected for this galaxy, along with modeling to shed light on these processes.”
The analysis revealed significant variation in the position and angle of the ring and jet, suggesting a physical relationship between particles and the event horizon, influencing the jet’s position. This study provides unique insights into the origin of very-high-energy gamma-ray emission during flares and could help resolve debates about cosmic rays detected on Earth.
By understanding these phenomena, scientists can gain valuable knowledge about particle acceleration near black holes and improve our comprehension of the universe’s most extreme environments.
Source: https://newsroom.ucla.edu/releases/astrophysicists-capture-huge-gamma-ray-flare-supermassive-black-hole-m87