Farhad Yusef-Zadeh
Northwestern University, IL·Astronomy & Astrophysics
At the center of the Milky Way sits a supermassive black hole, Sagittarius A* (Sgr A*), about 4 million times the mass of the Sun. Hot gas swirling toward it, called the accretion flow, gives off radio light that brightens and dims over hours.
- Fields
Astronomy & Astrophysics
Physics
- Topics
Sgr A*
Sagittarius A*
supermassive black hole
- Grants
- 1 known grant, through Jun 2027
What they work on
- Determine the magnetic field orientation of Sgr A*'s variable emission and relate it to the accretion flow's spin axis and the jet-like feature, using full-Stokes polarization analysis of expanding synchrotron hotspots.
- Characterize Sgr A*'s intrinsic variability by applying an adiabatic (expanding, cooling) hotspot model to simultaneous Very Large Array (VLA) and ALMA radio and millimeter observations.
- Determine the submillimeter-to-radio spectrum and emission variability of Sgr A* across multiple flares, using optical, infrared and radio light curves.
- Analyze a decade of archival VLA data to test whether hotspot properties around Sgr A* have changed over time, revealing the history of the accretion flow.
More about the research
Radio astronomers have recorded this flickering for about ten years. The pattern of these changes carries clues about how material moves near the black hole and which way the system spins. An important goal is to measure the direction the black hole's accretion flow rotates and compare it with the rotation of the whole galaxy.
Why it matters
This is basic astrophysics. Measuring the spin axis, magnetic field and long-term behavior of the gas around Sgr A* adds to our understanding of how supermassive black holes feed and how the black hole's rotation relates to that of the Milky Way. The project also includes public exhibits at Northwestern's main library on radio telescopes, radio images and how radio astronomy affects daily life.
Known grants
From NIH and NSF research grants. Labs often have other funding we can't see.
Closest labs
John Bally
University of Colorado Boulder, CO·Astronomy & Astrophysics
Map molecular gas across the entire Milky Way Central Molecular Zone at high resolution with the ALMA telescope as part of the ACES survey, tracing gas motions with more than a dozen molecular tracers.
Alanna Hughes
Wesleyan University, CT·Astronomy & Astrophysics
Improve methods for analyzing centimeter-wavelength (microwave) continuum emission from protoplanetary disks, focusing on VLA observations.
Kate Rowlands
Johns Hopkins University, MD·Astronomy & Astrophysics
Map recent star-formation histories in nearby galaxies using full spectral fitting of KILOGAS data, and compare them with current interstellar gas to see how star formation depends on available gas.
The school
Northwestern University: 71 labs on PI Pages, $1.3B a year on research, 536 research doctorates a year.
Reach out
A start for your email. Fill in the brackets.