Signals from the stars

Dr. Barak Zackay

New scientists

Date: September 14, 2020

Dr. Barak Zackay hunts for exotic astrophysical phenomena such as supernovae, binary black holes, pulsars, gravitational waves, and exoplanets. Stars generate a wide range of signals across the gravitational and electromagnetic spectrum as they rotate, merge, shrink into black holes where no light can escape, or explode in supernova bursts of energy and matter. Dr. Zackay has invented creative new techniques to record and analyze these interstellar signals.

History shows that every improvement in observational capabilities leads to great new discoveries in astronomy. Dr. Zackay, who joined the Department of Particle Physics and Astrophysics in 2020, applies math skills and a laser-like focus to finding new ways to extend the observational ability of astronomers. In his PhD research at the Weizmann Institute, he worked with colleagues to improve ways to discover supernovae. Their imaging-analysis tools are now widely used to help observatories continuously monitor the changing universe, and can alert the astronomers to supernova explosions in progress or other transient changes in the heavens, so that they could be observed and studied in detail as their images and radiation signatures reached Earth.

As he moved from analyzing light waves to the challenge of gravitational waves (which had first been measured in 2015), Dr. Zackay pioneered new tools to discover what these gravitational measurements can tell us about the universe.

Albert Einstein predicted gravitational waves in 1916 as part of his General Theory of Relativity, but they were not measured directly until 100 years later when researchers at the Laser Interferometer Gravitational-Wave Observatory (LIGO) and Virgo Scientific Collaboration announced they had evidence of gravitational waves caused by the merging of a binary black hole system. Sensing an emerging challenge to create new tools to observe what is going on in the universe, Dr. Zackay established a team at the Institute for Advanced Studies to examine the gravitational-wave signal data released from LIGO. Using analytical algorithms, he and his team discovered eight new binary black holes formed by the merging of two stars, just from analyzing the public data.

Dr. Zackay is also beginning to apply his algorithms and analysis to another fascinating problem: the origin of fast radio bursts (FRBs), which are extremely short bursts of energy emitted from different parts of the universe.  Moreover, he has ideas for signal-processing tools that could improve the quality of space-based imaging systems enough to see an exoplanet orbiting a distant sun. At his new lab on campus, he intends to gradually get these ideas from paper to reality in a series of projects combining algorithms and instruments, both in the lab and in the sky.