Pulling in an astronomy award

(Edmonton) A University of Alberta astronomer has won a prestigious prize for her investigation into an "oddly behaving" type of black hole. Jeanette Gladstone's work sheds new light on the previously unknown lifecycle of mysterious black holes. "Our research could have implications for the role of black holes in the evolution of entire galaxies," she says.

The American Astronomical Society awarded the High Energy Astrophysics Division Dissertation Prize to Gladstone to recognize her outstanding dissertation in high-energy astrophysics from among doctoral dissertations completed worldwide in the last three years.

"We focused our attention on relatively rare black holes that astronomers consider mysteriously over-bright," said Gladstone, a postdoctoral fellow in the Department of Physics. Researchers refer to these particular black holes as ultraluminous X-ray sources, or ULXs.

"On one hand, ULXs could be the missing link between stellar-mass black holes, which are the smallest known black holes and have about 10 times the mass of the sun, and super-massive black holes, which are the largest known, having hundreds of thousands to billions of times the mass of the sun," said Gladstone. There's also an alternative outcome to the research, she says. Gladstone says ULXs could contain a stellar-mass black hole that is rapidly pulling in more star stuff, surface material from stars, than scientists previously thought possible.

Combining data from XMM-Newton telescope operated by the European Space Agency, NASA's Chandra X-ray Observatory & Hubble Space Telescope, and the ground-based Gemini Observatory, Gladstone studied dozens of ULXs that lie within about 30 million light years from the Earth.

"Using the X-ray spectra of a dozen ULXs, we concluded that the black holes in ULXs are more likely to be stellar-mass black holes that are undergoing some of the most extreme activity in our universe," said Gladstone. "Astrophysical models that explain this extreme activity are at the forefront of ongoing research."

Gladstone began this research project while a PhD candidate at Durham University in the United Kingdom. She is now a post-doctoral fellow at the U of A. "I'm hoping to advance my research by trying to calculate the exact mass of black holes contained within ULXs."