A Hungry Black Hole Devoured a Star, and Its 'Burp' Reveals How It Chowed Down
By Nola Taylor Redd, Space.com Contributor | March 20, 2018 04:36pm ET
A black hole that's gobbling down a stellar meal is providing insight into how black holes devour matter and affect the evolution of galaxies.
Researchers found that the X-ray signal burst caused when a black hole shredded a passing star was repeated in the radio wavelengths nearly two weeks later. The radio echo most likely came from an exodus of highly energetic particles streaming out of the black hole, the researchers said.
In 2014, Las Cumbres Observatory's All-sky Automated Survey for Supernovae, a collection of robotic telescopes spread across the globe, picked up signals from 300 million light-years away. The event, known as ASASSN-14li, occurred as a star was ripped to shreds after passing too close to a black hole. Multiple telescopes immediately turned to track the tidal disruption flare, a powerful explosion of electromagnetic energy caused by the destruction. After poring through about six months' worth of data, Dheeraj Pasham, a researcher at the Massachusetts Institute of Technology, and Sjoert van Velzen, of Johns Hopkins University, found a pattern in the radio wavelength that nearly duplicates the X-ray signal. [No Escape: Dive Into a Black Hole (Infographic)]
"This is telling us the black hole feeding rate is controlling the strength of the jet it produces," Pasham said in a statement. "A well-fed black hole produces a strong jet, while a malnourished black hole produces a weak jet or no jet at all. This is the first time we've seen a jet that's controlled by a feeding supermassive black hole."
More:
https://www.space.com/40034-when-a-black-hole-chows-down.html