Keerthi Kunnumkai Earns Arnys Clifton Lilly Jr. Fellowship in Physics
Heidi Opdyke
- Associate Dean of Marketing and Communications, MCS
- Email opdyke@andrew.cmu.edu
- Phone 412-268-9982
Keerthi Kunnumkai gravitates to astrophysics.
"My research focuses on gravitational waves and their electromagnetic counterparts," said Kunnumkai, a graduate student in Carnegie Mellon University's Department of Physics. "Neutron star mergers are a key site for these counterparts, complementing gravitational wave observations."
Gravitational waves are ripples in spacetime that are produced when compact objects like neutron stars and black holes merge. When at least one neutron star is involved, these violent collisions can power r-process nucleosynthesis, a process that ejects neutron-rich matter and produces a kilonova — an electromagnetic flare visible in ultraviolet to infrared wavelengths for days.
Kunnumkai simulates gravitational wave events from mergers between binary neutron stars and neutron stars and black holes. She models their properties, such as mass, spin, sky location and viewing angles, and investigates how these properties affect the ejection of matter and potential kilonova signals.
Her work helps predict the optimal conditions for researchers to detect kilonovae and provides the necessary tools to astronomers, so they can decide when and how to follow up and what properties to look for.
"The r-process during kilonovae created most of the gold and platinum we see today," Kunnumkai said. "We've only observed one so far from neutron star mergers. My research helps ensure we don't miss the next one."
By studying kilonovae, astrophysicists can investigate the origins of heavy elements, probe the physics of extreme matter, test models of dense nuclear equations and understand how matter behaves under intense gravitational and magnetic fields.
Antonella Palmese, assistant professor of physics and Kunnumkai's advisor, said that Kunnamkai's work has the potential to accelerate the research into neutron star mergers.
"While a lot of previous work has been focused on binary neutron star mergers, neutron star-black hole mergers were not thought to be as promising multimessenger sources," Palmese said. "This is because we expected the black hole to engulf the neutron star entirely in most cases, leaving no matter to emit electromagnetic radiation. Recent gravitational wave observations have shown that neutron star-black hole pairs may actually have the right properties to leave matter outside and emit a kilonova. Keerthi's work is extremely important, as it shows that neutron star-black hole mergers are actually very promising multimessenger sources and what their expected optical emission is, so we can observe them with telescopes."
For her work, Kunnumkai earned the Arnys Clifton Lilly Jr. Fellowship in Physics, which honors graduate students doing exceptional research in physics. She said that the fellowship will allow her to expand her work to other gravitational wave counterparts like short gamma-ray bursts.
"It's really exciting to work on this," Kunnamkai said. "I get to know about the interesting things that are happening elsewhere in the universe and the processes behind them."
